/* ============================================================
   AI Proof Engineers landing page
   Standalone, zero-dependency CSS. Matches the app's design
   tokens (frontend/src/index.css): same palette, fonts, radii
   and light-theme behaviour, so the landing page and product
   feel like one thing.
   ============================================================ */

:root {
  --font-sans: "Inter", ui-sans-serif, system-ui, -apple-system, sans-serif;
  --font-display: "Manrope", "Inter", ui-sans-serif, system-ui, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, "SFMono-Regular", Menlo, monospace;

  --bg: #06070c;
  --bg-elev: #0a0c14;
  --bg-soft: #0e1119;
  --bg-card: rgba(14, 17, 25, 0.72);
  --bg-code: #0b0e17;
  --border: #1a1e2b;
  --border-strong: #262b3b;

  --text: #f4f5fa;
  --text-2: #b8bfd4;
  --text-3: #8890a9;
  --text-4: #757e9d;

  --brand: #818cf8;
  --brand-strong: #6366f1;
  --brand-deep: #4f46e5;
  --brand-soft: rgba(129, 140, 248, 0.12);
  --cyan: #22d3ee;
  --emerald: #34d399;
  --amber: #fbbf24;
  --rose: #f87171;

  --shadow-card: 0 1px 0 0 rgba(255, 255, 255, 0.04) inset, 0 1px 2px 0 rgba(0, 0, 0, 0.4);
  --shadow-lift: 0 24px 60px -24px rgba(0, 0, 0, 0.75);
  --shadow-glow: 0 0 0 1px rgba(129, 140, 248, 0.16), 0 12px 40px -12px rgba(99, 102, 241, 0.45);

  --radius-sm: 10px;
  --radius: 16px;
  --radius-lg: 22px;
  --container: 1180px;
  --header-h: 68px;
  color-scheme: dark;
}

:root[data-theme="light"] {
  --bg: #f6f7fb;
  --bg-elev: #ffffff;
  --bg-soft: #f3f4f8;
  --bg-card: rgba(255, 255, 255, 0.82);
  --bg-code: #0b0e17;
  --border: #dfe2ea;
  --border-strong: #c8cdd9;

  --text: #0e1120;
  --text-2: #454c60;
  --text-3: #585f74;
  --text-4: #5f667d;

  --brand: #4f46e5;
  --brand-strong: #6366f1;
  --brand-deep: #4338ca;
  --brand-soft: rgba(99, 102, 241, 0.09);
  /* Text-safe on white and on the pale tinted badges (WCAG AA 4.5:1). */
  --cyan: #0e7490;
  --emerald: #047857;
  --amber: #b45309;
  --rose: #be123c;

  --shadow-card: 0 1px 2px 0 rgba(15, 23, 42, 0.06), 0 1px 3px 0 rgba(15, 23, 42, 0.04);
  --shadow-lift: 0 24px 60px -30px rgba(15, 23, 42, 0.28);
  --shadow-glow: 0 0 0 1px rgba(99, 102, 241, 0.2), 0 12px 40px -14px rgba(99, 102, 241, 0.35);
  color-scheme: light;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 20px);
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  min-height: 100vh;
  overflow-x: hidden;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -3;
  pointer-events: none;
  background:
    radial-gradient(ellipse 80% 50% at 50% -20%, rgba(99, 102, 241, 0.18), transparent),
    radial-gradient(ellipse 60% 40% at 100% 0%, rgba(34, 211, 238, 0.08), transparent);
}

:root[data-theme="light"] body::before {
  background:
    radial-gradient(ellipse 80% 50% at 50% -20%, rgba(99, 102, 241, 0.1), transparent),
    radial-gradient(ellipse 60% 40% at 100% 0%, rgba(34, 211, 238, 0.06), transparent);
}

img,
svg {
  display: block;
  max-width: 100%;
}

a {
  color: inherit;
  text-decoration: none;
}

button,
input,
summary {
  font: inherit;
}

h1, h2, h3, h4 {
  margin: 0;
  font-family: var(--font-display);
  color: var(--text);
  text-wrap: balance;
}

p {
  margin: 0;
}

ul, ol {
  margin: 0;
  padding: 0;
  list-style: none;
}

::selection {
  background: rgba(129, 140, 248, 0.35);
  color: #fff;
}

:where(a, button, summary, [tabindex]):focus-visible {
  outline: 2px solid var(--brand);
  outline-offset: 3px;
  border-radius: 6px;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 100;
  padding: 10px 16px;
  border-radius: var(--radius-sm);
  background: var(--brand-deep);
  color: #fff;
  font-weight: 600;
  transform: translateY(-160%);
  transition: transform 0.2s ease;
}

.skip-link:focus {
  transform: translateY(0);
}

.container {
  width: min(var(--container), calc(100% - 3rem));
  margin-inline: auto;
}

.page-grid {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: -1;
  opacity: 0.5;
  background-image:
    linear-gradient(to right, rgba(129, 140, 248, 0.055) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(129, 140, 248, 0.055) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: radial-gradient(ellipse 75% 55% at 50% 0%, #000 20%, transparent 75%);
  -webkit-mask-image: radial-gradient(ellipse 75% 55% at 50% 0%, #000 20%, transparent 75%);
}

:root[data-theme="light"] .page-grid {
  opacity: 0.6;
  background-image:
    linear-gradient(to right, rgba(79, 70, 229, 0.06) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(79, 70, 229, 0.06) 1px, transparent 1px);
}
/* ---------- Type & shared bits ---------- */

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 14px;
  color: var(--brand);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.eyebrow::before {
  content: "";
  width: 18px;
  height: 2px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--brand), var(--cyan));
}

.gradient-text {
  background: linear-gradient(100deg, var(--brand) 10%, var(--cyan) 90%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hide-sm {
  display: none;
}

.section {
  position: relative;
  padding: clamp(4.5rem, 9vw, 7.5rem) 0;
}

.section-alt {
  border-block: 1px solid var(--border);
  background:
    linear-gradient(180deg, rgba(129, 140, 248, 0.035), transparent 30%),
    var(--bg-elev);
}

:root[data-theme="light"] .section-alt {
  background:
    linear-gradient(180deg, rgba(99, 102, 241, 0.035), transparent 30%),
    var(--bg-elev);
}

.section-head {
  max-width: 720px;
  margin: 0 auto clamp(2.5rem, 5vw, 4rem);
  text-align: center;
}

.section-head h2,
.split-copy h2 {
  font-size: clamp(1.9rem, 4vw, 3rem);
  font-weight: 800;
  letter-spacing: -0.035em;
  line-height: 1.12;
}

.section-lede {
  margin-top: 18px;
  color: var(--text-2);
  font-size: clamp(1rem, 1.5vw, 1.1rem);
  line-height: 1.75;
}

.section-head .section-lede {
  margin-inline: auto;
}

/* ---------- Buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  padding: 13px 22px;
  border: 1px solid transparent;
  border-radius: 12px;
  font-family: var(--font-sans);
  font-size: 14.5px;
  font-weight: 600;
  line-height: 1;
  white-space: nowrap;
  cursor: pointer;
  transition: transform 0.18s ease, box-shadow 0.18s ease, background 0.18s ease, border-color 0.18s ease, color 0.18s ease;
}

.btn svg {
  width: 16px;
  height: 16px;
  flex: none;
  transition: transform 0.18s ease;
}

.btn:hover svg {
  transform: translateX(2px);
}

.btn-primary {
  background: linear-gradient(135deg, var(--brand-strong), var(--brand-deep));
  color: #fff;
  box-shadow: var(--shadow-glow);
}

.btn-primary:hover {
  filter: brightness(1.09);
  transform: translateY(-1px);
}

.btn-outline {
  border-color: var(--border-strong);
  background: transparent;
  color: var(--text);
}

.btn-outline:hover {
  border-color: var(--brand);
  background: var(--brand-soft);
  color: var(--text);
}

.btn-secondary {
  border-color: var(--border-strong);
  background: var(--bg-soft);
  color: var(--text);
}

.btn-secondary:hover {
  border-color: var(--brand);
  background: var(--bg-card);
}

.btn-ghost {
  padding-inline: 12px;
  background: transparent;
  color: var(--text-2);
}

.btn-ghost:hover {
  color: var(--text);
}

.btn-sm {
  padding: 10px 16px;
  border-radius: 10px;
  font-size: 13.5px;
}

.btn-lg {
  padding: 16px 26px;
  border-radius: 13px;
  font-size: 15.5px;
}

/* ---------- Header ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  height: var(--header-h);
  border-bottom: 1px solid transparent;
  transition: background 0.25s ease, border-color 0.25s ease, backdrop-filter 0.25s ease;
}

.site-header.is-scrolled,
.site-header.is-open {
  border-bottom-color: var(--border);
  background: var(--bg);
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
}

.nav-inner {
  display: flex;
  height: var(--header-h);
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  flex: none;
}

.brand-mark {
  width: 32px;
  height: 32px;
  border-radius: 9px;
  box-shadow: 0 0 0 1px var(--border-strong);
}

.brand-word {
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 800;
  letter-spacing: 0.06em;
}

.primary-nav {
  display: flex;
  align-items: center;
  gap: 4px;
}

.primary-nav a {
  padding: 8px 12px;
  border-radius: 8px;
  color: var(--text-2);
  font-size: 14px;
  font-weight: 500;
  transition: color 0.15s ease, background 0.15s ease;
}

.primary-nav a:hover,
.primary-nav a.is-active {
  background: var(--brand-soft);
  color: var(--text);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 6px;
  flex: none;
}

.icon-button {
  display: inline-grid;
  place-items: center;
  width: 38px;
  height: 38px;
  border: 1px solid transparent;
  border-radius: 10px;
  background: transparent;
  color: var(--text-3);
  cursor: pointer;
  transition: color 0.15s ease, background 0.15s ease, border-color 0.15s ease;
}

.icon-button:hover {
  border-color: var(--border);
  background: var(--bg-soft);
  color: var(--text);
}

.icon-button svg {
  width: 18px;
  height: 18px;
}

.theme-toggle .icon-sun,
:root[data-theme="light"] .theme-toggle .icon-moon {
  display: none;
}

:root[data-theme="light"] .theme-toggle .icon-sun {
  display: block;
}

.nav-toggle {
  display: none;
}

.nav-toggle[aria-expanded="true"] {
  background: var(--brand-soft);
  color: var(--text);
}
/* ---------- Hero ---------- */

.hero {
  position: relative;
  /* The decorative glow sits at right: -12%. Clip only the horizontal
     overflow so it can never widen the document on a phone. `hidden` is the
     fallback for browsers without `clip`. */
  overflow-x: hidden;
  overflow-x: clip;
  padding: clamp(2.5rem, 5vw, 4rem) 0 clamp(3rem, 6vw, 4.5rem);
}

.hero::before {
  content: "";
  position: absolute;
  top: -12%;
  right: -12%;
  width: 56vw;
  height: 56vw;
  max-width: 780px;
  max-height: 780px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(99, 102, 241, 0.22), transparent 65%);
  filter: blur(30px);
  pointer-events: none;
  z-index: -1;
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.04fr) minmax(0, 0.96fr);
  gap: clamp(2.5rem, 5vw, 4.5rem);
  align-items: center;
}

.pill {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 7px 13px;
  border: 1px solid var(--border-strong);
  border-radius: 999px;
  background: color-mix(in srgb, var(--bg-soft) 70%, transparent);
  color: var(--text-2);
  font-size: 12.5px;
  font-weight: 600;
  letter-spacing: 0.01em;
  transition: border-color 0.18s ease, color 0.18s ease;
}

.pill:hover {
  border-color: var(--brand);
  color: var(--text);
}

.pill svg {
  width: 13px;
  height: 13px;
  color: var(--brand);
}

.pill-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--emerald);
  box-shadow: 0 0 0 3px rgba(52, 211, 153, 0.16);
  animation: pulse-dot 2.4s ease-in-out infinite;
}

.pill-solid {
  border-color: color-mix(in srgb, var(--brand) 40%, transparent);
  background: var(--brand-soft);
  color: var(--text);
}

@keyframes pulse-dot {
  0%, 100% { box-shadow: 0 0 0 3px rgba(52, 211, 153, 0.16); }
  50% { box-shadow: 0 0 0 6px rgba(52, 211, 153, 0.04); }
}

.hero h1 {
  margin-top: 22px;
  font-size: clamp(2.65rem, 5.6vw, 4.5rem);
  font-weight: 800;
  letter-spacing: -0.05em;
  line-height: 1.03;
}

.hero-lede {
  max-width: 580px;
  margin-top: 24px;
  color: var(--text-2);
  font-size: clamp(1rem, 1.35vw, 1.115rem);
  line-height: 1.78;
}

.hero-lede em {
  color: var(--text);
  font-style: normal;
  font-weight: 600;
}

.hero-ctas {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

.hero-points {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 22px;
  margin-top: 28px;
  color: var(--text-3);
  font-size: 13.5px;
}

.hero-points li {
  display: flex;
  align-items: center;
  gap: 7px;
}

.hero-points svg {
  width: 14px;
  height: 14px;
  color: var(--emerald);
}

/* ---------- Product preview ---------- */

.hero-visual {
  position: relative;
  min-width: 0;
}

.app-frame {
  position: relative;
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  background: var(--bg-elev);
  background: linear-gradient(180deg, color-mix(in srgb, var(--bg-soft) 94%, transparent), var(--bg-elev));
  box-shadow: var(--shadow-lift), 0 0 0 1px rgba(255, 255, 255, 0.02) inset;
  overflow: hidden;
  transform: perspective(1400px) rotateY(-3deg) rotateX(1.5deg);
  transform-origin: center left;
  transition: transform 0.5s cubic-bezier(0.16, 1, 0.3, 1);
}

.app-frame:hover {
  transform: perspective(1400px) rotateY(0deg) rotateX(0deg);
}

.app-chrome {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 11px 16px;
  border-bottom: 1px solid var(--border);
  background: color-mix(in srgb, var(--bg-elev) 70%, transparent);
}

.window-dots {
  display: flex;
  gap: 5px;
  flex: none;
}

.window-dots i {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--border-strong);
}

.window-dots i:first-child { background: #f87171aa; }
.window-dots i:nth-child(2) { background: #fbbf24aa; }
.window-dots i:last-child { background: #34d399aa; }

.app-path {
  flex: 1;
  color: var(--text-4);
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.01em;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.app-saved {
  display: flex;
  align-items: center;
  gap: 4px;
  flex: none;
  color: var(--text-4);
  font-size: 10.5px;
}

.app-saved svg {
  width: 11px;
  height: 11px;
  color: var(--emerald);
}

.preview-tabs {
  display: flex;
  gap: 4px;
  padding: 10px 14px 0;
  border-bottom: 1px solid var(--border);
}

.preview-tab {
  position: relative;
  padding: 8px 11px 12px;
  border: 0;
  background: transparent;
  color: var(--text-3);
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  transition: color 0.15s ease;
}

.preview-tab:hover {
  color: var(--text);
}

.preview-tab.is-active {
  color: var(--text);
}

.preview-tab.is-active::after {
  content: "";
  position: absolute;
  right: 8px;
  bottom: -1px;
  left: 8px;
  height: 2px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--brand), var(--cyan));
}

.preview-body {
  padding: 18px;
  min-height: 392px;
}

.preview-panel {
  animation: panel-in 0.32s cubic-bezier(0.16, 1, 0.3, 1) both;
}

@keyframes panel-in {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: none; }
}

.preview-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 18px;
}

.preview-kicker {
  margin-bottom: 3px;
  color: var(--text-4);
  font-size: 10px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.preview-title,
.report-head h3 {
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.3;
  color: var(--text);
}

.band {
  display: inline-flex;
  padding: 4px 9px;
  border: 1px solid transparent;
  border-radius: 999px;
  font-size: 10.5px;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.band-strong {
  border-color: rgba(52, 211, 153, 0.3);
  background: rgba(52, 211, 153, 0.11);
  color: var(--emerald);
}
.mastery-rows {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.mrow-label,
.report-row-top {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 5px;
  color: var(--text-2);
  font-size: 11.5px;
  font-weight: 500;
}

.mrow-label span:last-child,
.report-row-top span:last-child {
  color: var(--text-4);
  font-family: var(--font-mono);
  font-size: 10.5px;
}

.mbar {
  height: 6px;
  border-radius: 999px;
  background: var(--border);
  overflow: hidden;
}

.mbar > span {
  display: block;
  width: var(--value);
  height: 100%;
  border-radius: inherit;
  background: linear-gradient(90deg, var(--brand-strong), var(--cyan));
  animation: bar-grow 1s cubic-bezier(0.16, 1, 0.3, 1) both;
}

.mbar > .is-warm {
  background: linear-gradient(90deg, #f59e0b, var(--amber));
}

.mbar > .is-low {
  background: linear-gradient(90deg, #e11d48, var(--rose));
}

@keyframes bar-grow {
  from { width: 0; }
}

.preview-note {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  margin-top: 18px;
  padding: 11px 12px;
  border: 1px solid rgba(129, 140, 248, 0.22);
  border-radius: 11px;
  background: var(--brand-soft);
  color: var(--text-2);
  font-size: 11px;
  line-height: 1.55;
}

.preview-note svg {
  width: 15px;
  height: 15px;
  flex: none;
  margin-top: 1px;
  color: var(--brand);
}

.preview-note strong {
  color: var(--text);
  font-weight: 600;
}

.mini-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
  margin-top: 16px;
}

.mini-stats > div {
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 10px 11px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: color-mix(in srgb, var(--bg-elev) 62%, transparent);
}

.mini-stats span {
  color: var(--text-4);
  font-size: 9.5px;
  letter-spacing: 0.02em;
}

.mini-stats strong {
  color: var(--text);
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 700;
  line-height: 1.2;
}

/* Sandbox tab */

.code-card {
  border: 1px solid var(--border);
  border-radius: 11px;
  background: var(--bg-code);
  overflow: hidden;
}

.code-card-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  padding: 8px 12px;
  border-bottom: 1px solid #1c2030;
  color: #8890a9;
  font-family: var(--font-mono);
  font-size: 10px;
}

.chip {
  display: inline-flex;
  align-items: center;
  padding: 3px 8px;
  border: 1px solid var(--border-strong);
  border-radius: 999px;
  color: var(--text-3);
  font-size: 9.5px;
  font-weight: 600;
  letter-spacing: 0.02em;
  white-space: nowrap;
}

.chip-cyan {
  border-color: rgba(34, 211, 238, 0.28);
  background: rgba(34, 211, 238, 0.08);
  color: #22d3ee;
}

pre.code {
  margin: 0;
  padding: 13px 12px;
  overflow-x: auto;
  color: #d6dcf0;
  font-family: var(--font-mono);
  font-size: 10.5px;
  line-height: 1.65;
  tab-size: 2;
}

.c-key { color: #c4b5fd; }
.c-type { color: #7dd3fc; }
.c-num { color: #fca5a5; }

.test-list {
  display: flex;
  flex-direction: column;
  gap: 1px;
  margin-top: 14px;
  border: 1px solid var(--border);
  border-radius: 11px;
  overflow: hidden;
}

.test-list li {
  display: flex;
  align-items: center;
  gap: 9px;
  padding: 8px 11px;
  background: color-mix(in srgb, var(--bg-elev) 62%, transparent);
  color: var(--text-2);
  font-size: 11px;
}

.test-list li + li {
  border-top: 1px solid var(--border);
}

.tick {
  display: inline-grid;
  place-items: center;
  width: 15px;
  height: 15px;
  flex: none;
  border-radius: 50%;
  font-size: 9px;
  font-weight: 700;
}

.tick-pass {
  background: rgba(52, 211, 153, 0.14);
  color: var(--emerald);
}

.test-tag {
  margin-left: auto;
  color: var(--emerald);
  font-family: var(--font-mono);
  font-size: 9px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.verdict {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  margin-top: 14px;
  padding: 11px 13px;
  border: 1px solid rgba(52, 211, 153, 0.24);
  border-radius: 11px;
  background: rgba(52, 211, 153, 0.07);
}

.verdict-ok {
  color: var(--emerald);
  font-size: 12px;
  font-weight: 700;
}

.verdict-meta {
  color: var(--text-4);
  font-family: var(--font-mono);
  font-size: 9.5px;
}
/* Review tab */

.review-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  margin-bottom: 12px;
}

.mono {
  color: var(--text-2);
  font-family: var(--font-mono);
  font-size: 11px;
}

.review-lines {
  padding: 9px 0;
  border: 1px solid var(--border);
  border-radius: 11px;
  background: var(--bg-code);
  overflow: hidden;
}

.rline {
  display: flex;
  gap: 12px;
  padding: 2px 0;
  color: #8890a9;
  font-family: var(--font-mono);
  font-size: 10px;
  line-height: 1.7;
  white-space: nowrap;
}

.ln {
  width: 26px;
  flex: none;
  padding-right: 9px;
  border-right: 1px solid #1c2030;
  color: #4b5570;
  text-align: right;
  user-select: none;
}

.hl {
  display: inline-block;
  margin-block: -1px;
  padding-block: 1px;
  border-radius: 2px;
}

.hl-bug { background: rgba(251, 113, 133, 0.18); box-shadow: inset 2px 0 0 #fb7185; }
.hl-design { background: rgba(251, 191, 36, 0.15); box-shadow: inset 2px 0 0 #fbbf24; }

.findings {
  display: flex;
  flex-direction: column;
  gap: 7px;
  margin-top: 13px;
}

.finding {
  display: flex;
  align-items: flex-start;
  gap: 9px;
  padding: 9px 11px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: color-mix(in srgb, var(--bg-elev) 62%, transparent);
}

.sev {
  flex: none;
  padding: 2px 6px;
  border-radius: 5px;
  font-size: 8.5px;
  font-weight: 700;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.sev-bug { background: rgba(251, 113, 133, 0.13); color: var(--rose); }
.sev-design { background: rgba(251, 191, 36, 0.13); color: var(--amber); }

.finding p {
  display: flex;
  flex-direction: column;
  gap: 1px;
  font-size: 10.5px;
  line-height: 1.45;
}

.finding strong {
  color: var(--text-2);
  font-weight: 600;
}

.finding p span {
  color: var(--emerald);
  font-size: 9.5px;
}

.finding p .muted {
  color: var(--rose);
}

.floating-chip {
  position: absolute;
  right: -12px;
  bottom: -16px;
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 9px 14px;
  border: 1px solid var(--border-strong);
  border-radius: 999px;
  background: color-mix(in srgb, var(--bg-elev) 92%, transparent);
  box-shadow: var(--shadow-lift);
  color: var(--text-2);
  font-size: 11.5px;
  font-weight: 600;
  white-space: nowrap;
}

.floating-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--emerald);
}

/* ---------- Stat strip ---------- */

.stat-strip {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  margin-top: clamp(3rem, 6vw, 4.5rem);
  border-block: 1px solid var(--border);
}

.stat {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 20px clamp(12px, 2vw, 26px);
}

.stat + .stat {
  border-left: 1px solid var(--border);
}

.stat strong {
  color: var(--text);
  font-family: var(--font-display);
  font-size: clamp(1.55rem, 2.6vw, 2.1rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.1;
  font-variant-numeric: tabular-nums;
}

.stat span {
  color: var(--text-3);
  font-size: 12px;
  line-height: 1.45;
}
/* ---------- Feature cards ---------- */

.card {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-card);
  box-shadow: var(--shadow-card);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.feature-card {
  position: relative;
  display: flex;
  flex-direction: column;
  padding: 26px 24px;
  overflow: hidden;
  transition: border-color 0.25s ease, transform 0.25s ease, box-shadow 0.25s ease;
}

.feature-card::before {
  content: "";
  position: absolute;
  top: -60px;
  right: -40px;
  width: 160px;
  height: 160px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(99, 102, 241, 0.16), transparent 70%);
  pointer-events: none;
  transition: opacity 0.25s ease;
  opacity: 0.7;
}

.feature-card:hover {
  border-color: color-mix(in srgb, var(--brand) 45%, var(--border));
  transform: translateY(-3px);
  box-shadow: var(--shadow-lift);
}

.icon-tile {
  display: inline-grid;
  place-items: center;
  width: 42px;
  height: 42px;
  margin-bottom: 20px;
  border: 1px solid rgba(129, 140, 248, 0.28);
  border-radius: 12px;
  background: var(--brand-soft);
  color: var(--brand);
}

.icon-tile svg {
  width: 21px;
  height: 21px;
}

.icon-tile-cyan {
  border-color: rgba(34, 211, 238, 0.26);
  background: rgba(34, 211, 238, 0.08);
  color: var(--cyan);
}

.icon-tile-emerald {
  border-color: rgba(52, 211, 153, 0.26);
  background: rgba(52, 211, 153, 0.08);
  color: var(--emerald);
}

.feature-card h3 {
  margin-bottom: 10px;
  font-size: 18.5px;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.feature-card > p {
  color: var(--text-2);
  font-size: 14.5px;
  line-height: 1.7;
}

.check-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-top: 18px;
  padding-top: 18px;
  border-top: 1px solid var(--border);
}

.check-list li {
  position: relative;
  padding-left: 24px;
  color: var(--text-3);
  font-size: 13px;
  line-height: 1.5;
}

.check-list li::before {
  content: "";
  position: absolute;
  top: 0.42em;
  left: 2px;
  width: 12px;
  height: 7px;
  border-bottom: 2px solid var(--emerald);
  border-left: 2px solid var(--emerald);
  transform: rotate(-45deg);
  opacity: 0.9;
}

.check-list-plain li::before {
  border-color: var(--brand);
}

.principle-bar {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  margin-top: 20px;
  padding: 20px 22px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: linear-gradient(100deg, var(--brand-soft), transparent 55%);
}

.principle-icon {
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  flex: none;
  border-radius: 10px;
  background: var(--brand-soft);
  color: var(--brand);
}

.principle-icon svg {
  width: 19px;
  height: 19px;
}

.principle-bar p {
  color: var(--text-2);
  font-size: 14px;
  line-height: 1.7;
}

.principle-bar strong {
  display: block;
  margin-bottom: 2px;
  color: var(--text);
  font-size: 14.5px;
  font-weight: 600;
}

/* ---------- Subjects ---------- */

.subject-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.subject-card {
  display: flex;
  flex-direction: column;
  padding: 24px;
  transition: border-color 0.25s ease, transform 0.25s ease;
}

.subject-card:hover {
  border-color: color-mix(in srgb, var(--brand) 45%, var(--border));
  transform: translateY(-3px);
}

.subject-card-highlight {
  border-color: color-mix(in srgb, var(--brand) 35%, var(--border));
  background:
    linear-gradient(160deg, var(--brand-soft), transparent 55%),
    var(--bg-card);
}

.subject-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  margin-bottom: 18px;
}

.subject-tag {
  display: inline-flex;
  padding: 4px 9px;
  border: 1px solid transparent;
  border-radius: 7px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  font-weight: 700;
  letter-spacing: 0.08em;
}

.tag-dsa { border-color: rgba(129, 140, 248, 0.3); background: rgba(129, 140, 248, 0.12); color: var(--brand); }
.tag-lld { border-color: rgba(34, 211, 238, 0.26); background: rgba(34, 211, 238, 0.08); color: var(--cyan); }
.tag-sql { border-color: rgba(52, 211, 153, 0.26); background: rgba(52, 211, 153, 0.08); color: var(--emerald); }
.tag-hld { border-color: rgba(251, 191, 36, 0.28); background: rgba(251, 191, 36, 0.08); color: var(--amber); }
.tag-lang { border-color: rgba(244, 114, 182, 0.26); background: rgba(244, 114, 182, 0.08); color: #f472b6; }
.tag-plus { border-color: var(--border-strong); background: var(--bg-soft); color: var(--text-3); font-size: 13px; }

:root[data-theme="light"] .tag-lang { color: #be185d; }

.subject-meta {
  color: var(--text-4);
  font-family: var(--font-mono);
  font-size: 10.5px;
  text-align: right;
}

.subject-card h3 {
  margin-bottom: 9px;
  font-size: 17.5px;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.subject-card > p {
  color: var(--text-2);
  font-size: 13.5px;
  line-height: 1.7;
}

.tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 16px;
}

.tag-row li {
  padding: 3px 8px;
  border: 1px solid var(--border);
  border-radius: 999px;
  color: var(--text-3);
  font-size: 10.5px;
}

.text-link {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  margin-top: auto;
  padding-top: 20px;
  color: var(--brand);
  font-size: 13px;
  font-weight: 600;
}

.text-link span {
  transition: transform 0.18s ease;
}

.text-link:hover span {
  transform: translateX(3px);
}
/* ---------- Steps & formats ---------- */

.steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  counter-reset: step;
}

.step {
  position: relative;
  padding: 26px 24px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: linear-gradient(180deg, var(--bg-card), transparent);
}

.step::after {
  content: "";
  position: absolute;
  top: 50px;
  right: -19px;
  width: 20px;
  height: 1px;
  background: linear-gradient(90deg, var(--border-strong), transparent);
}

.step:last-child::after {
  display: none;
}

.step-number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  margin-bottom: 18px;
  border: 1px solid var(--border-strong);
  border-radius: 10px;
  background: var(--bg-soft);
  color: var(--brand);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
}

.step h3 {
  margin-bottom: 9px;
  font-size: 17.5px;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.step p {
  color: var(--text-2);
  font-size: 13.5px;
  line-height: 1.7;
}

.step-foot {
  display: block;
  margin-top: 16px;
  color: var(--text-4);
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.03em;
}

.formats {
  margin-top: 20px;
  padding: 24px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-card);
}

.formats-label {
  margin-bottom: 18px;
  color: var(--text-3);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.format-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
}

.format-grid li {
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 12px 13px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: color-mix(in srgb, var(--bg-elev) 55%, transparent);
  color: var(--text-2);
  font-size: 12.5px;
  font-weight: 600;
}

.format-grid svg {
  width: 17px;
  height: 17px;
  margin-bottom: 7px;
  color: var(--brand);
  stroke-width: 1.7;
}

.format-grid span {
  color: var(--text-4);
  font-size: 10.5px;
  font-weight: 400;
}

/* ---------- Mastery split ---------- */

.split {
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(0, 0.98fr);
  gap: clamp(2.5rem, 5vw, 4.5rem);
  align-items: center;
}

.mastery-list {
  display: flex;
  flex-direction: column;
  gap: 18px;
  margin-top: 30px;
}

.mastery-list li {
  display: flex;
  gap: 13px;
  align-items: flex-start;
}

.mastery-icon {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  flex: none;
  border: 1px solid var(--border);
  border-radius: 9px;
  background: var(--bg-soft);
  color: var(--brand);
}

.mastery-icon svg {
  width: 17px;
  height: 17px;
}

.mastery-list strong {
  display: block;
  margin-bottom: 2px;
  color: var(--text);
  font-size: 14.5px;
  font-weight: 600;
}

.mastery-list p {
  color: var(--text-3);
  font-size: 13px;
  line-height: 1.6;
}

.report-wrap {
  position: relative;
}

.report-card {
  position: relative;
  padding: 24px;
}

.report-card::before {
  content: "";
  position: absolute;
  inset: -1px;
  border-radius: inherit;
  padding: 1px;
  background: linear-gradient(140deg, rgba(129, 140, 248, 0.5), transparent 40%, rgba(34, 211, 238, 0.25));
  -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  pointer-events: none;
}

.report-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 16px;
}

.report-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 14px;
  margin-bottom: 20px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--border);
  color: var(--text-4);
  font-size: 9.5px;
}

.report-legend span {
  display: flex;
  align-items: center;
  gap: 5px;
}

.dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
}

.dot-rose { background: var(--rose); }
.dot-amber { background: var(--amber); }
.dot-emerald { background: var(--emerald); }

.report-rows {
  display: flex;
  flex-direction: column;
  gap: 15px;
}

.report-row-top {
  margin-bottom: 6px;
  color: var(--text-2);
  font-size: 12.5px;
}

.report-row-top .pct {
  font-size: 10.5px;
  font-weight: 600;
}

.pct-low { color: var(--rose); }
.pct-mid { color: var(--amber); }
.pct-strong { color: var(--emerald); }

.report-caption {
  margin-top: 5px;
  color: var(--text-4);
  font-size: 10.5px;
}

.report-rows .mbar {
  height: 7px;
}

.misconception {
  margin-top: 20px;
  padding: 13px 14px;
  border: 1px dashed color-mix(in srgb, var(--brand) 45%, transparent);
  border-radius: 11px;
  background: var(--brand-soft);
}

.misconception-label {
  display: block;
  margin-bottom: 5px;
  color: var(--brand);
  font-size: 9.5px;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.misconception p {
  color: var(--text-2);
  font-size: 12px;
  line-height: 1.6;
}

.misconception em {
  color: var(--text);
  font-family: var(--font-mono);
  font-size: 11px;
  font-style: normal;
}

.report-cta {
  width: 100%;
  margin-top: 18px;
}
/* ---------- Comparison ---------- */

.table-wrap {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-card);
  box-shadow: var(--shadow-card);
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.compare-table {
  width: 100%;
  min-width: 700px;
  border-collapse: collapse;
  font-size: 13.5px;
}

.compare-table th,
.compare-table td {
  padding: 15px 20px;
  text-align: left;
  vertical-align: top;
  border-bottom: 1px solid var(--border);
}

.compare-table thead th {
  padding-block: 17px;
  background: color-mix(in srgb, var(--bg-soft) 70%, transparent);
  color: var(--text-3);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.compare-table thead th:first-child {
  width: 20%;
}

.compare-table tbody th {
  color: var(--text-2);
  font-size: 13px;
  font-weight: 600;
}

.compare-table tbody td {
  color: var(--text-3);
}

.compare-table tbody tr:last-child th,
.compare-table tbody tr:last-child td {
  border-bottom: 0;
}

.compare-table .col-sedu {
  background: color-mix(in srgb, var(--brand) 5%, transparent);
  color: var(--text);
  font-weight: 500;
}

.compare-table thead .col-sedu {
  color: var(--brand);
}

.yes {
  position: relative;
  padding-left: 21px;
}

.yes::before {
  content: "";
  position: absolute;
  top: 0.35em;
  left: 0;
  width: 11px;
  height: 6px;
  border-bottom: 2px solid var(--emerald);
  border-left: 2px solid var(--emerald);
  transform: rotate(-45deg);
}

.table-note {
  max-width: 760px;
  margin: 16px auto 0;
  color: var(--text-4);
  font-size: 11.5px;
  line-height: 1.6;
  text-align: center;
}

/* ---------- Hero additions ---------- */

.hero-eyebrow {
  margin: 22px 0 12px;
  color: var(--text-3);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.band-moderate {
  border-color: rgba(129, 140, 248, 0.32);
  background: var(--brand-soft);
  color: var(--brand);
}

.band-developing {
  border-color: rgba(251, 191, 36, 0.3);
  background: rgba(251, 191, 36, 0.1);
  color: var(--amber);
}

.band-none {
  border-color: var(--border-strong);
  background: var(--bg-soft);
  color: var(--text-3);
}

.mrow .band {
  padding: 2px 8px;
  font-size: 9.5px;
}

/* Four segments, one per evidence band: a band is a level, not a percentage. */
.seg-meter {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 4px;
}

.seg-meter i {
  height: 6px;
  border-radius: 3px;
  background: var(--border);
}

.seg-meter[data-level="4"] i { background: var(--emerald); }
.seg-meter[data-level="3"] i:nth-child(-n + 3) { background: var(--brand); }
.seg-meter[data-level="2"] i:nth-child(-n + 2) { background: var(--amber); }
.seg-meter[data-level="1"] i:nth-child(1) { background: var(--text-4); }

.card-link:hover {
  color: var(--brand);
}

.persona-kicker {
  margin-bottom: 10px;
  color: var(--brand);
  font-size: 11.5px;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.persona-grid .feature-card {
  display: flex;
  flex-direction: column;
}

/* ---------- Pricing ---------- */

.pricing-controls {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 12px;
  margin: -1rem 0 2rem;
}

.billing-toggle {
  display: inline-flex;
  padding: 4px;
  border: 1px solid var(--border-strong);
  border-radius: 999px;
  background: var(--bg-soft);
}

.billing-toggle button {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 40px;
  padding: 0 16px;
  border: 0;
  border-radius: 999px;
  background: none;
  color: var(--text-3);
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
}

.billing-toggle button[aria-checked="true"] {
  background: var(--bg-elev);
  color: var(--text);
  box-shadow: var(--shadow-card), 0 0 0 1px var(--border-strong);
}

.save-badge {
  padding: 2px 7px;
  border-radius: 999px;
  background: rgba(52, 211, 153, 0.12);
  color: var(--emerald);
  font-size: 11px;
  font-weight: 700;
}

.currency-picker select {
  min-height: 42px;
  padding: 0 34px 0 14px;
  border: 1px solid var(--border-strong);
  border-radius: 999px;
  background:
    url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%238890a9' stroke-width='2'%3E%3Cpath d='m6 9 6 6 6-6'/%3E%3C/svg%3E") right 12px center / 14px no-repeat,
    var(--bg-soft);
  color: var(--text-2);
  font: inherit;
  font-size: 14px;
  font-weight: 600;
  appearance: none;
  cursor: pointer;
}

.currency-picker select:focus-visible {
  outline: 2px solid var(--brand);
  outline-offset: 3px;
}

html:not(.js) .pricing-controls {
  display: none;
}

.pricing-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
  max-width: 900px;
  margin: 0 auto;
}

.price-card {
  display: flex;
  flex-direction: column;
  padding: clamp(24px, 3vw, 34px);
}

.price-card-pro {
  border-color: color-mix(in srgb, var(--brand) 45%, var(--border));
  background:
    linear-gradient(160deg, var(--brand-soft), transparent 60%),
    var(--bg-card);
  box-shadow: var(--shadow-glow);
}

.price-card-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.price-card h3 {
  font-size: 20px;
  font-weight: 800;
  letter-spacing: -0.02em;
}

.price-tagline {
  margin-top: 6px;
  color: var(--text-3);
  font-size: 14px;
}

.price {
  display: flex;
  align-items: baseline;
  gap: 6px;
  margin-top: 22px;
}

.price-amount {
  font-family: var(--font-display);
  font-size: clamp(2.6rem, 5vw, 3.2rem);
  font-weight: 800;
  letter-spacing: -0.04em;
  line-height: 1;
}

.price-unit {
  color: var(--text-3);
  font-size: 15px;
}

.price-note {
  min-height: 1.6em;
  margin-top: 8px;
  color: var(--text-3);
  font-size: 13.5px;
}

.price-cta {
  justify-content: center;
  width: 100%;
  margin-top: 22px;
}

.price-card .check-list li {
  font-size: 13.5px;
}

.trust-row {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px 28px;
  margin-top: 28px;
  color: var(--text-3);
  font-size: 13px;
}

.trust-row li {
  display: flex;
  align-items: center;
  gap: 8px;
}

.trust-row svg {
  width: 16px;
  height: 16px;
  color: var(--emerald);
}

/* ---------- Mobile sticky call to action ---------- */

.mobile-cta,
.nav-menu-only {
  display: none;
}

@media (max-width: 680px) {
  .js .mobile-cta {
    position: fixed;
    right: 0;
    bottom: 0;
    left: 0;
    z-index: 40;
    display: grid;
    grid-template-columns: 1fr 1.4fr;
    gap: 10px;
    padding: 10px 16px calc(10px + env(safe-area-inset-bottom));
    border-top: 1px solid var(--border);
    background: color-mix(in srgb, var(--bg) 92%, transparent);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    transform: translateY(110%);
    transition: transform 0.25s ease;
  }

  .js .mobile-cta.is-visible {
    transform: none;
  }

  .mobile-cta .btn {
    justify-content: center;
  }

  .js body.has-mobile-cta .site-footer {
    padding-bottom: 72px;
  }

  .pricing-grid {
    grid-template-columns: 1fr;
  }
}

/* ---------- Course pages (written by tools/landing/build.py) ---------- */

.page-hero {
  padding: clamp(2.5rem, 6vw, 4.5rem) 0 clamp(2rem, 5vw, 3.5rem);
}

.breadcrumbs ol {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 22px;
  color: var(--text-4);
  font-size: 13px;
}

.breadcrumbs li + li::before {
  content: "/";
  margin-right: 6px;
  color: var(--border-strong);
}

.breadcrumbs a:hover {
  color: var(--text);
}

.page-hero h1 {
  max-width: 820px;
  font-size: clamp(2.2rem, 5vw, 3.6rem);
  font-weight: 800;
  letter-spacing: -0.045em;
  line-height: 1.06;
}

.page-hero .hero-lede {
  max-width: 720px;
}

.fact-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 26px;
}

.fact-row li {
  padding: 6px 12px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--bg-soft);
  color: var(--text-2);
  font-size: 13px;
}

.fact-row strong {
  color: var(--text);
  font-family: var(--font-display);
}

.prose {
  max-width: 760px;
}

.prose h2 {
  margin-bottom: 14px;
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: 800;
  letter-spacing: -0.03em;
}

.prose p + p {
  margin-top: 14px;
}

.prose p {
  color: var(--text-2);
  line-height: 1.75;
}

.curriculum {
  display: grid;
  gap: 12px;
  margin-top: 28px;
}

.topic-block {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-card);
}

.topic-block summary {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
  padding: 18px 22px;
  cursor: pointer;
  list-style: none;
}

.topic-block summary::-webkit-details-marker {
  display: none;
}

.topic-block h3 {
  font-size: 17px;
  font-weight: 700;
}

.topic-meta {
  flex-shrink: 0;
  color: var(--text-4);
  font-family: var(--font-mono);
  font-size: 11.5px;
}

.topic-body {
  padding: 0 22px 20px;
}

.topic-body > p {
  color: var(--text-3);
  font-size: 14px;
  line-height: 1.7;
}

.module-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 16px 24px;
  margin-top: 16px;
}

.module-list h4 {
  margin-bottom: 6px;
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 13.5px;
  font-weight: 700;
}

.module-list li li {
  position: relative;
  padding-left: 14px;
  color: var(--text-3);
  font-size: 13px;
  line-height: 1.65;
}

.module-list li li::before {
  content: "";
  position: absolute;
  top: 0.65em;
  left: 2px;
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--brand);
}

.problem-groups {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 16px;
  margin-top: 28px;
}

.problem-group {
  padding: 20px 22px;
}

.problem-group h3 {
  margin-bottom: 10px;
  font-size: 15px;
  font-weight: 700;
}

.problem-group li {
  display: flex;
  justify-content: space-between;
  gap: 10px;
  padding: 6px 0;
  border-top: 1px solid var(--border);
  color: var(--text-2);
  font-size: 13.5px;
}

.problem-group li:first-child {
  border-top: 0;
}

.problem-group .chip {
  flex-shrink: 0;
  align-self: center;
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 14px;
  margin-top: 24px;
}

.related-grid a {
  display: block;
  padding: 18px 20px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-card);
  transition: border-color 0.2s ease;
}

.related-grid a:hover {
  border-color: color-mix(in srgb, var(--brand) 45%, var(--border));
}

.related-grid strong {
  display: block;
  font-family: var(--font-display);
  font-size: 15px;
}

.related-grid span {
  display: block;
  margin-top: 4px;
  color: var(--text-3);
  font-size: 13px;
}

.section-tight {
  padding: clamp(2.5rem, 6vw, 4.5rem) 0;
}













/* ---------- FAQ ---------- */

.faq-layout {
  display: grid;
  grid-template-columns: minmax(0, 0.78fr) minmax(0, 1.22fr);
  gap: clamp(2rem, 4vw, 4rem);
  align-items: start;
}

.faq-intro {
  position: sticky;
  top: calc(var(--header-h) + 28px);
}

.faq-intro h2 {
  font-size: clamp(1.9rem, 3.5vw, 2.6rem);
  font-weight: 800;
  letter-spacing: -0.035em;
  line-height: 1.12;
}

.faq-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.faq-item {
  border: 1px solid var(--border);
  border-radius: 13px;
  background: var(--bg-card);
  transition: border-color 0.2s ease, background 0.2s ease;
}

.faq-item:hover {
  border-color: var(--border-strong);
}

.faq-item[open] {
  border-color: color-mix(in srgb, var(--brand) 40%, var(--border));
  background: color-mix(in srgb, var(--brand) 4%, var(--bg-card));
}

.faq-item summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 17px 20px;
  color: var(--text);
  font-size: 14.5px;
  font-weight: 600;
  line-height: 1.5;
  cursor: pointer;
  list-style: none;
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-plus {
  position: relative;
  width: 16px;
  height: 16px;
  flex: none;
}

.faq-plus::before,
.faq-plus::after {
  content: "";
  position: absolute;
  top: 7px;
  left: 2px;
  width: 12px;
  height: 1.5px;
  border-radius: 2px;
  background: var(--text-3);
  transition: transform 0.2s ease, background 0.2s ease;
}

.faq-plus::after {
  transform: rotate(90deg);
}

.faq-item[open] .faq-plus::after {
  transform: rotate(0deg);
}

.faq-item[open] .faq-plus::before,
.faq-item[open] .faq-plus::after {
  background: var(--brand);
}

.faq-item p {
  padding: 0 20px 19px;
  color: var(--text-2);
  font-size: 13.5px;
  line-height: 1.75;
}
/* ---------- Final CTA ---------- */

.final-cta {
  padding: clamp(3rem, 6vw, 5rem) 0 clamp(4rem, 7vw, 6rem);
}

.final-card {
  position: relative;
  padding: clamp(36px, 7vw, 72px) clamp(24px, 5vw, 56px);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  background:
    radial-gradient(ellipse 60% 100% at 50% 0%, rgba(99, 102, 241, 0.22), transparent 65%),
    var(--bg-elev);
  box-shadow: var(--shadow-lift);
  text-align: center;
  overflow: hidden;
}

.final-card h2 {
  font-size: clamp(2rem, 4.5vw, 3.2rem);
  font-weight: 800;
  letter-spacing: -0.04em;
  line-height: 1.08;
}

.final-card > p:not(.eyebrow, .final-fineprint) {
  max-width: 560px;
  margin: 18px auto 0;
  color: var(--text-2);
  font-size: 15px;
  line-height: 1.75;
}

.final-ctas {
  justify-content: center;
}

.final-fineprint {
  margin-top: 18px;
  color: var(--text-4);
  font-size: 11.5px;
}

/* ---------- Footer ---------- */

.site-footer {
  border-top: 1px solid var(--border);
  background: var(--bg-elev);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.6fr repeat(2, 1fr) 1.1fr;
  gap: clamp(2rem, 4vw, 3.5rem);
  padding-block: clamp(2.5rem, 5vw, 4rem);
}

.footer-brand p {
  max-width: 320px;
  margin-top: 14px;
  color: var(--text-3);
  font-size: 12.5px;
  line-height: 1.7;
}


.footer-col {
  display: flex;
  flex-direction: column;
  gap: 9px;
}

.footer-col h2,
.footer-col h3 {
  margin-bottom: 4px;
  color: var(--text);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.footer-col a,
.footer-col span {
  width: fit-content;
  color: var(--text-3);
  font-size: 12.5px;
  transition: color 0.15s ease;
}

.footer-col a:hover {
  color: var(--text);
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding-block: 18px;
  border-top: 1px solid var(--border);
  color: var(--text-4);
  font-size: 11px;
}

.footer-built {
  text-align: right;
}

/* ---------- Try-a-question demo ---------- */

.demo {
  display: grid;
  grid-template-columns: minmax(0, 0.8fr) minmax(0, 1.5fr);
  gap: clamp(1.5rem, 4vw, 3.5rem);
  align-items: start;
  margin-top: clamp(3rem, 6vw, 4.5rem);
}

.demo-intro {
  position: sticky;
  top: calc(var(--header-h) + 24px);
}

.demo-intro h3 {
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.15;
}

.demo-intro p:not(.eyebrow) {
  margin-top: 14px;
  color: var(--text-2);
  line-height: 1.7;
}

.demo-card {
  padding: clamp(20px, 3vw, 30px);
}

.demo-title {
  margin: 4px 0 14px;
  font-size: 19px;
  font-weight: 700;
}

.demo-statement {
  display: grid;
  gap: 10px;
  color: var(--text-2);
  font-size: 14px;
}

.demo-statement code,
.demo-explanation code,
.demo-option code,
.demo-static code {
  padding: 1px 5px;
  border-radius: 5px;
  background: var(--bg-soft);
  color: var(--text);
  font-family: var(--font-mono);
  font-size: 0.88em;
}

.demo-table {
  overflow-x: auto;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
}

.demo-table table {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--font-mono);
  font-size: 12px;
}

.demo-table th,
.demo-table td {
  padding: 6px 10px;
  border-bottom: 1px solid var(--border);
  text-align: left;
  white-space: nowrap;
}

.demo-table th {
  background: var(--bg-soft);
  color: var(--text);
  font-weight: 600;
}

.demo-table tr:last-child td {
  border-bottom: 0;
}

pre.demo-code {
  border-radius: var(--radius-sm);
  background: var(--bg-code);
  font-size: 12.5px;
}

/* The inline-code chip above must not reach the code block's own <code>. */
pre.demo-code code {
  padding: 0;
  border-radius: 0;
  background: none;
  color: inherit;
  font-size: inherit;
}

.demo-options {
  display: grid;
  gap: 10px;
  margin-top: 20px;
}

.demo-option {
  display: flex;
  align-items: center;
  gap: 12px;
  width: 100%;
  min-height: 48px;
  padding: 10px 14px;
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  background: var(--bg-soft);
  color: var(--text);
  font-size: 14.5px;
  text-align: left;
  cursor: pointer;
  transition: border-color 0.15s ease, background-color 0.15s ease;
}

.demo-option:hover:not(:disabled) {
  border-color: color-mix(in srgb, var(--brand) 55%, var(--border-strong));
}

.demo-option:disabled {
  cursor: default;
}

.demo-letter {
  display: inline-grid;
  flex-shrink: 0;
  place-items: center;
  width: 26px;
  height: 26px;
  border: 1px solid var(--border-strong);
  border-radius: 7px;
  color: var(--text-3);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
}

.demo-option.is-right {
  border-color: var(--emerald);
  background: color-mix(in srgb, var(--emerald) 12%, var(--bg-soft));
}

.demo-option.is-right .demo-letter {
  border-color: var(--emerald);
  color: var(--emerald);
}

.demo-option.is-wrong {
  border-color: var(--rose);
  background: color-mix(in srgb, var(--rose) 10%, var(--bg-soft));
}

.demo-option.is-wrong .demo-letter {
  border-color: var(--rose);
  color: var(--rose);
}

.demo-feedback {
  margin-top: 20px;
  padding-top: 18px;
  border-top: 1px solid var(--border);
}

.demo-verdict {
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 800;
}

.demo-verdict.is-right {
  color: var(--emerald);
}

.demo-verdict.is-wrong {
  color: var(--rose);
}

.demo-misconception {
  margin-top: 10px;
  padding: 10px 12px;
  border: 1px solid color-mix(in srgb, var(--amber) 40%, var(--border));
  border-radius: var(--radius-sm);
  background: color-mix(in srgb, var(--amber) 8%, transparent);
  color: var(--text-2);
  font-size: 14px;
}

.demo-misconception strong {
  color: var(--amber);
}

.demo-explanation {
  margin-top: 12px;
  color: var(--text-2);
  font-size: 14px;
  line-height: 1.7;
}

.demo-ctas {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 18px;
}

.demo-static {
  margin-top: 18px;
  color: var(--text-2);
  font-size: 14px;
}

.demo-static summary {
  color: var(--brand);
  font-weight: 600;
  cursor: pointer;
}

.demo-static > p,
.demo-static > div {
  margin-top: 10px;
}

/* With JS the buttons do the job; the static answer is for readers without it. */
.js .demo-static {
  display: none;
}

html:not(.js) .demo-option {
  cursor: default;
}

/* ---------- Footer email signup ---------- */

.footer-signup {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.2fr);
  gap: 18px 40px;
  align-items: center;
  padding-block: clamp(2rem, 4vw, 2.75rem);
  border-bottom: 1px solid var(--border);
}

.footer-signup h2 {
  font-size: 19px;
  font-weight: 800;
  letter-spacing: -0.02em;
}

.footer-signup-copy p {
  margin-top: 6px;
  color: var(--text-3);
  font-size: 14px;
}

.signup-row {
  display: flex;
  gap: 10px;
}

.signup-row input {
  flex: 1;
  min-width: 0;
  min-height: 44px;
  padding: 0 14px;
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  background: var(--bg);
  color: var(--text);
  font: inherit;
  font-size: 14.5px;
}

.signup-row input::placeholder {
  color: var(--text-4);
}

.signup-row input:focus-visible,
.signup-consent input:focus-visible {
  outline: 2px solid var(--brand);
  outline-offset: 2px;
}

.signup-consent {
  display: flex;
  align-items: flex-start;
  gap: 9px;
  margin-top: 10px;
  color: var(--text-3);
  font-size: 12.5px;
  line-height: 1.5;
  cursor: pointer;
}

.signup-consent input {
  flex-shrink: 0;
  width: 16px;
  height: 16px;
  margin-top: 1px;
  accent-color: var(--brand-strong);
}

.signup-status {
  min-height: 1.4em;
  margin-top: 8px;
  font-size: 13px;
}

.signup-status.is-ok {
  color: var(--emerald);
}

.signup-status.is-error {
  color: var(--rose);
}

/* The honeypot: off-screen rather than display:none, which some bots skip. */
.signup-trap {
  position: absolute;
  left: -10000px;
  width: 1px;
  height: 1px;
  overflow: hidden;
}

/* The form needs JS to post; without it, show nothing rather than a dead form. */
html:not(.js) .footer-signup {
  display: none;
}

/* ---------- Testimonials (only rendered with real, permitted quotes) ---------- */

.testimonials {
  border-top: 1px solid var(--border);
}

.quote-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 18px;
}

.quote-card {
  margin: 0;
  padding: 24px;
}

.quote-card blockquote {
  margin: 0;
  color: var(--text);
  font-size: 15px;
  line-height: 1.7;
}

.quote-card figcaption {
  display: grid;
  gap: 2px;
  margin-top: 16px;
  font-size: 13px;
}

.quote-card figcaption span {
  color: var(--text-3);
}

.used-by {
  margin-top: 28px;
  color: var(--text-3);
  font-size: 14px;
  text-align: center;
}

@media (max-width: 980px) {
  .demo,
  .footer-signup {
    grid-template-columns: 1fr;
  }

  .demo-intro {
    position: static;
  }
}

@media (max-width: 480px) {
  .signup-row {
    flex-direction: column;
  }
}

/* ---------- Scroll reveal ---------- */

.js .reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.65s cubic-bezier(0.16, 1, 0.3, 1), transform 0.65s cubic-bezier(0.16, 1, 0.3, 1);
  transition-delay: var(--reveal-delay, 0ms);
}

.js .reveal.is-visible {
  opacity: 1;
  transform: none;
}

/* A small stagger for grids: children reveal in sequence. */
.js .feature-grid > .reveal:nth-child(2),
.js .subject-grid > .reveal:nth-child(2),
.js .steps > .reveal:nth-child(2) { --reveal-delay: 80ms; }
.js .feature-grid > .reveal:nth-child(3),
.js .subject-grid > .reveal:nth-child(3),
.js .steps > .reveal:nth-child(3) { --reveal-delay: 160ms; }
.js .subject-grid > .reveal:nth-child(4) { --reveal-delay: 80ms; }
.js .subject-grid > .reveal:nth-child(5) { --reveal-delay: 160ms; }
.js .subject-grid > .reveal:nth-child(6) { --reveal-delay: 240ms; }
/* ---------- Responsive ---------- */

@media (min-width: 640px) {
  .hide-sm {
    display: block;
  }
}

@media (max-width: 1080px) {
  .primary-nav {
    gap: 0;
  }

  .primary-nav a {
    padding-inline: 9px;
    font-size: 13px;
  }

  .feature-grid,
  .subject-grid,
  .steps {
    grid-template-columns: repeat(2, 1fr);
  }

  .step::after {
    display: none;
  }

  .format-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .footer-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .footer-brand {
    grid-column: 1 / -1;
  }

  .footer-col:last-child {
    grid-column: auto;
  }
}

@media (max-width: 980px) {
  .hero-grid,
  .split,
  .faq-layout {
    grid-template-columns: 1fr;
  }

  .hero {
    padding-top: 2rem;
  }

  .hero-copy {
    max-width: 720px;
  }

  .hero-visual {
    max-width: 620px;
    margin-inline: auto;
    width: 100%;
  }

  .app-frame {
    transform: none;
  }

  .faq-intro {
    position: static;
  }



  .stat-strip {
    grid-template-columns: repeat(2, 1fr);
  }

  .stat:nth-child(3) {
    border-left: 0;
    border-top: 1px solid var(--border);
  }

  .stat:nth-child(4) {
    border-top: 1px solid var(--border);
  }
}

@media (max-width: 860px) {
  :root {
    --header-h: 62px;
  }

  .nav-toggle {
    display: inline-grid;
  }

  .primary-nav {
    position: absolute;
    top: var(--header-h);
    right: 0;
    left: 0;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    padding: 10px 24px 18px;
    border-bottom: 1px solid var(--border);
    /* Solid: a backdrop blur doesn't work inside the header's own blur, so a
       translucent menu let the page's text show through the links. */
    background: var(--bg);
    box-shadow: var(--shadow-lift);
  }

  .site-header.is-open .primary-nav {
    display: flex;
  }

  .primary-nav a {
    padding: 12px;
    font-size: 15px;
  }

  .nav-cta,
  .nav-login {
    display: none;
  }

  .site-header.is-open .nav-menu-only {
    display: flex;
  }

  .primary-nav .nav-menu-cta {
    justify-content: center;
    margin-top: 8px;
    color: #fff;
  }

  .hero h1 {
    font-size: clamp(2.4rem, 9vw, 3.4rem);
  }
}

@media (max-width: 680px) {
  .container {
    width: calc(100% - 2.25rem);
  }

  .feature-grid,
  .subject-grid,
  .steps,

  .format-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .footer-col:last-child {
    grid-column: auto;
  }

  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
    gap: 4px;
  }

  .footer-built {
    text-align: left;
  }

  .hero-ctas .btn {
    width: 100%;
  }

  .hero-points {
    gap: 8px 16px;
  }

  /* The 2x2 stat grid from the 980px breakpoint stays: it fits at 390px and
     keeps this strip from becoming four full-width rows. */

  .preview-body {
    min-height: 0;
    padding: 14px;
  }

  .floating-chip {
    right: 50%;
    bottom: -14px;
    transform: translateX(50%);
    font-size: 10.5px;
  }

  .mini-stats {
    grid-template-columns: repeat(3, 1fr);
  }

  .compare-table th,
  .compare-table td {
    padding: 12px 14px;
  }

  .report-card,
  .feature-card,
  .subject-card,
  .step,
  .formats {
    padding: 20px;
  }

  .principle-bar {
    flex-direction: column;
    gap: 12px;
  }
}

/* ---------- No-JS / failed-JS fallback ----------
   `.js` is added before first paint by theme-init.js. If scripting is off, or
   a script fails and removes it again, expose the nav and every preview panel
   instead of leaving them behind non-functional controls. */

html:not(.js) .theme-toggle,
html:not(.js) .nav-toggle {
  display: none;
}

html:not(.js) .site-header {
  border-bottom-color: var(--border);
  background: var(--bg);
}

html:not(.js) .preview-tabs {
  display: none;
}

html:not(.js) .preview-panel[hidden] {
  display: block;
}

html:not(.js) .preview-panel + .preview-panel {
  margin-top: 18px;
  padding-top: 18px;
  border-top: 1px solid var(--border);
}

@media (max-width: 860px) {
  html:not(.js) .site-header {
    height: auto;
  }

  html:not(.js) .nav-inner {
    height: auto;
    flex-wrap: wrap;
    padding-block: 10px;
  }

  html:not(.js) .brand {
    order: 0;
  }

  html:not(.js) .nav-actions {
    order: 1;
    margin-left: auto;
  }

  html:not(.js) .primary-nav {
    order: 2;
    position: static;
    display: flex;
    flex-direction: row;
    flex-wrap: wrap;
    width: 100%;
    gap: 2px;
    padding: 6px 0 2px;
    border: 0;
    background: none;
    box-shadow: none;
    backdrop-filter: none;
  }

  html:not(.js) .primary-nav a {
    padding: 8px 10px;
  }

  html:not(.js) .nav-cta,
  html:not(.js) .primary-nav .nav-menu-only:not(.btn) {
    display: inline-flex;
  }

  html:not(.js) {
    scroll-padding-top: 190px;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  .js .reveal {
    opacity: 1;
    transform: none;
  }

  .app-frame {
    transform: none;
  }
}