/* We Teach AI — Neural Indigo palette
   Frontier-AI aesthetic: indigo + violet + cyan on near-black.
*/

:root {
  --bg:         #0B0B14;
  --bg-elev:    #13132A;
  --bg-soft:    #1B1B3A;
  --ink:        #E6E7F2;
  --ink-soft:   #A6A8C2;
  --ink-dim:    #6E708F;
  --indigo:     #1E1B4B;
  --indigo-deep:#15123A;
  --violet:     #7C3AED;
  --violet-deep:#5B21B6;
  --violet-soft:rgba(124, 58, 237, .14);
  --cyan:       #22D3EE;
  --cyan-deep:  #0891B2;
  --cyan-soft:  rgba(34, 211, 238, .12);
  --line:       #252548;
  --line-soft:  #1F1F3D;
  --ok:         #34D399;
  --warn:       #F59E0B;
  --err:        #F87171;
  --shadow:     0 1px 2px rgba(0,0,0,.4), 0 8px 24px rgba(124, 58, 237, .12);
  --shadow-lg:  0 4px 12px rgba(0,0,0,.5), 0 24px 60px rgba(124, 58, 237, .18);
  --glow:       0 0 0 1px rgba(124,58,237,.4), 0 0 24px rgba(124,58,237,.25);
  --radius:     14px;
  --radius-sm:  8px;
  --container:  1180px;
  --font-sans:  'Inter', system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
  --font-display:'Space Grotesk', 'Inter', system-ui, sans-serif;
  --font-mono:  'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font-sans);
  color: var(--ink);
  background:
    radial-gradient(900px 600px at 90% -10%, rgba(124,58,237,.18), transparent 60%),
    radial-gradient(700px 500px at -10% 110%, rgba(34,211,238,.10), transparent 60%),
    var(--bg);
  background-attachment: fixed;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

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

a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(34,211,238,.25);
  transition: color .15s ease, border-color .15s ease;
}
a:hover {
  color: var(--violet);
  border-bottom-color: var(--violet);
}

h1, h2, h3, h4 {
  font-family: var(--font-display);
  color: var(--ink);
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.15;
  margin: 0 0 .6em;
}
h1 { font-size: clamp(2.2rem, 5vw, 3.8rem); }
h2 { font-size: clamp(1.7rem, 3vw, 2.4rem); }
h3 { font-size: 1.25rem; }

p { margin: 0 0 1em; }
code, kbd, .mono {
  font-family: var(--font-mono);
  background: var(--bg-soft);
  padding: .12em .4em;
  border-radius: 4px;
  font-size: .92em;
  color: var(--cyan);
}

.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 1.25rem;
}

.muted { color: var(--ink-soft); }
.dim { color: var(--ink-dim); }
.small { font-size: .9rem; }
.center { text-align: center; }

.eyebrow {
  display: inline-block;
  font-family: var(--font-sans);
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--cyan);
  background: var(--cyan-soft);
  padding: .35rem .85rem;
  border-radius: 999px;
  margin-bottom: 1rem;
  border: 1px solid rgba(34,211,238,.2);
}
.eyebrow-violet {
  color: var(--violet);
  background: var(--violet-soft);
  border-color: rgba(124,58,237,.25);
}

.skip-link {
  position: absolute; left: -9999px; top: 0;
  background: var(--violet); color: var(--ink);
  padding: .5rem .75rem; z-index: 1000;
}
.skip-link:focus { left: 1rem; top: 1rem; }

/* Header */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(11, 11, 20, .8);
  backdrop-filter: blur(14px) saturate(180%);
  -webkit-backdrop-filter: blur(14px) saturate(180%);
  border-bottom: 1px solid var(--line);
}
.header-row {
  display: flex; align-items: center; justify-content: space-between;
  padding: .9rem 1.25rem;
}
.brand {
  display: inline-flex; align-items: center; gap: .65rem;
  color: var(--ink); font-weight: 600; border: none;
  font-family: var(--font-display); font-size: 1.15rem;
  letter-spacing: -.02em;
}
.brand:hover { color: var(--violet); }
.brand-mark {
  display: inline-grid; place-items: center;
  width: 36px; height: 36px;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--violet), var(--cyan));
  color: #0B0B14;
  font-family: var(--font-display);
  font-weight: 800; font-size: 1.1rem;
  box-shadow: var(--shadow), 0 0 24px rgba(124,58,237,.4);
  position: relative;
  overflow: hidden;
}
.brand-mark::after {
  content: '';
  position: absolute; inset: 0;
  background: linear-gradient(135deg, transparent 30%, rgba(255,255,255,.2) 50%, transparent 70%);
  mix-blend-mode: overlay;
}

.primary-nav { display: flex; align-items: center; gap: 1.5rem; }
.primary-nav a {
  color: var(--ink-soft);
  font-weight: 500;
  border: none;
  font-size: .96rem;
}
.primary-nav a:hover { color: var(--ink); }
.primary-nav a.active { color: var(--ink); }
.nav-cta {
  background: linear-gradient(135deg, var(--violet), var(--violet-deep));
  color: #fff !important;
  padding: .55rem 1.2rem; border-radius: 8px;
  font-weight: 600 !important;
  font-size: .9rem !important;
  border: 1px solid rgba(255,255,255,.08);
  box-shadow: 0 0 0 1px rgba(124,58,237,.4), 0 8px 20px rgba(124,58,237,.25);
}
.nav-cta:hover {
  background: linear-gradient(135deg, var(--cyan), var(--violet));
  color: #0B0B14 !important;
}

.nav-ghost {
  color: var(--ink) !important;
  border: 1px solid var(--line) !important;
  padding: .5rem 1rem; border-radius: 8px;
  font-size: .9rem !important;
  font-weight: 500 !important;
}
.nav-ghost:hover { border-color: var(--violet) !important; }

.nav-toggle {
  display: none;
  background: none; border: 0; padding: .4rem; cursor: pointer;
  width: 40px; height: 40px;
}
.nav-toggle span {
  display: block; width: 22px; height: 2px; background: var(--ink);
  margin: 5px auto; border-radius: 2px; transition: transform .2s, opacity .2s;
}

@media (max-width: 880px) {
  .nav-toggle { display: block; }
  .primary-nav {
    position: absolute; top: 100%; right: 0; left: 0;
    background: var(--bg-elev); border-bottom: 1px solid var(--line);
    flex-direction: column; align-items: stretch; gap: 0;
    padding: .5rem 1.25rem 1rem;
    max-height: 0; overflow: hidden;
    transition: max-height .25s ease;
  }
  .primary-nav.open { max-height: 600px; }
  .primary-nav a { padding: .8rem 0; border-bottom: 1px solid var(--line-soft); }
  .primary-nav a:last-child { border-bottom: 0; }
  .nav-cta, .nav-ghost { margin-top: .5rem; text-align: center; }
}

/* Flash */
.flash-stack { margin-top: 1rem; }
.flash {
  padding: .8rem 1rem; border-radius: var(--radius-sm);
  background: var(--bg-elev); border: 1px solid var(--line);
  margin-bottom: .5rem;
  color: var(--ink);
}
.flash-success { border-left: 3px solid var(--ok); }
.flash-error   { border-left: 3px solid var(--err); }
.flash-warning { border-left: 3px solid var(--warn); }

/* Buttons */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  gap: .5rem;
  padding: .85rem 1.5rem; border-radius: 10px;
  font-weight: 600; font-size: .98rem;
  border: 1px solid transparent; cursor: pointer;
  text-decoration: none;
  transition: background .15s, color .15s, border-color .15s, transform .08s, box-shadow .2s;
  font-family: var(--font-sans);
}
.btn:active { transform: translateY(1px); }
.btn-primary {
  background: linear-gradient(135deg, var(--violet), var(--violet-deep));
  color: #fff; border: none;
  box-shadow: 0 0 0 1px rgba(124,58,237,.5), 0 8px 24px rgba(124,58,237,.3);
}
.btn-primary:hover {
  background: linear-gradient(135deg, var(--cyan), var(--violet));
  box-shadow: 0 0 0 1px rgba(34,211,238,.5), 0 12px 32px rgba(34,211,238,.3);
}
.btn-ghost {
  background: transparent; color: var(--ink);
  border-color: var(--line);
}
.btn-ghost:hover {
  border-color: var(--violet); color: var(--ink);
  background: var(--violet-soft);
}
.btn-cyan {
  background: linear-gradient(135deg, var(--cyan), var(--cyan-deep));
  color: #0B0B14; border: none; font-weight: 700;
}
.btn-cyan:hover { filter: brightness(1.1); }
.btn.full { display: flex; width: 100%; }
.btn-sm { padding: .55rem 1rem; font-size: .88rem; border-radius: 8px; }
.btn-lg { padding: 1.1rem 1.8rem; font-size: 1.05rem; border-radius: 12px; }

/* Hero */
.hero {
  padding: clamp(3rem, 7vw, 6rem) 0 clamp(2.5rem, 5vw, 4rem);
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute; inset: 0;
  background:
    radial-gradient(800px 400px at 70% 30%, rgba(124,58,237,.15), transparent 60%),
    radial-gradient(600px 400px at 20% 70%, rgba(34,211,238,.10), transparent 60%);
  pointer-events: none;
}
.hero-grid {
  display: grid; gap: clamp(2rem, 4vw, 3rem);
  grid-template-columns: 1.2fr 1fr; align-items: center;
  position: relative;
}
@media (max-width: 960px) { .hero-grid { grid-template-columns: 1fr; } }
.hi {
  background: linear-gradient(120deg, var(--violet), var(--cyan));
  -webkit-background-clip: text; background-clip: text;
  color: transparent;
}
.lede {
  font-size: clamp(1.05rem, 1.3vw, 1.2rem);
  color: var(--ink-soft);
  max-width: 38em;
}

.trust-row {
  display: flex; flex-wrap: wrap; gap: .55rem; margin-top: 1.5rem;
}
.trust-pill {
  display: inline-flex; align-items: center;
  background: var(--bg-elev); border: 1px solid var(--line);
  padding: .4rem .9rem; border-radius: 999px;
  font-size: .82rem; color: var(--ink-soft);
  font-weight: 500;
}

.hero-card {
  background: linear-gradient(180deg, var(--bg-elev), var(--indigo-deep));
  border-radius: var(--radius);
  padding: 1.85rem;
  border: 1px solid var(--line);
  box-shadow: var(--shadow-lg);
  position: relative;
  overflow: hidden;
}
.hero-card::before {
  content: '';
  position: absolute; top: 0; left: 0; right: 0; height: 1px;
  background: linear-gradient(90deg, transparent, var(--violet), var(--cyan), transparent);
}
.card-h {
  font-family: var(--font-sans);
  font-size: .72rem; font-weight: 700; letter-spacing: .18em;
  text-transform: uppercase; color: var(--cyan);
  margin-bottom: .35rem;
}
.card-title { font-size: 1.4rem; margin-bottom: .35rem; }

/* Section + alt */
.section { padding: clamp(3rem, 6vw, 5rem) 0; }
.section-alt {
  background: var(--bg-elev);
  border-block: 1px solid var(--line);
}
.section-head { margin-bottom: 2.5rem; max-width: 42em; }

/* Course grid (catalog) */
.course-grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.5rem;
}
@media (max-width: 920px) { .course-grid { grid-template-columns: 1fr; } }

.course-card {
  position: relative;
  background: var(--bg-elev);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.75rem;
  box-shadow: var(--shadow);
  transition: transform .2s, border-color .2s, box-shadow .2s;
  display: flex; flex-direction: column;
  overflow: hidden;
}
.course-card::before {
  content: '';
  position: absolute; top: 0; left: 0; right: 0; height: 3px;
  background: linear-gradient(90deg, var(--violet), var(--cyan));
  opacity: .8;
}
.course-card:hover {
  transform: translateY(-3px);
  border-color: rgba(124,58,237,.5);
  box-shadow: var(--shadow-lg);
}
.course-card h3 { font-size: 1.4rem; margin-bottom: .5rem; }
.course-card .badge {
  position: absolute; top: 1rem; right: 1rem;
  background: var(--violet-soft); color: var(--violet);
  font-size: .7rem; font-weight: 700;
  letter-spacing: .12em; text-transform: uppercase;
  padding: .3rem .75rem; border-radius: 999px;
  border: 1px solid rgba(124,58,237,.3);
}
.course-card .price {
  font-family: var(--font-display);
  font-size: 1.8rem; font-weight: 600;
  color: var(--cyan);
  margin: .5rem 0;
}
.course-card .price small {
  font-family: var(--font-sans);
  font-size: .82rem; color: var(--ink-dim);
  font-weight: 400;
}
.course-card .desc {
  color: var(--ink-soft); flex-grow: 1; margin-bottom: 1.25rem;
}
.course-card .meta {
  font-size: .82rem; color: var(--ink-dim);
  display: flex; gap: 1rem; margin-bottom: 1rem;
}
.course-card .meta span::before { content: '· '; color: var(--violet); }
.course-card .meta span:first-child::before { content: none; }

/* Forms */
.form-stack { display: grid; gap: 1rem; max-width: 36em; margin-top: 1rem; }
.form-stack .row { display: grid; gap: .35rem; }
.form-stack label {
  font-weight: 600; font-size: .9rem; color: var(--ink);
}
.form-stack input,
.form-stack textarea,
.form-stack select {
  width: 100%; font: inherit; color: var(--ink);
  padding: .75rem .9rem;
  background: var(--bg-soft);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  transition: border-color .15s, box-shadow .15s;
  font-family: var(--font-sans);
}
.form-stack input::placeholder,
.form-stack textarea::placeholder { color: var(--ink-dim); }
.form-stack input:focus,
.form-stack textarea:focus,
.form-stack select:focus {
  outline: 0;
  border-color: var(--violet);
  box-shadow: 0 0 0 3px var(--violet-soft);
}
.form-stack .err { color: var(--err); font-size: .88rem; margin: 0; }
.form-stack .help { color: var(--ink-dim); font-size: .85rem; margin: 0; }

/* Footer */
.site-footer {
  background: var(--indigo-deep); color: var(--ink-soft);
  padding: 3.5rem 0 1.5rem;
  margin-top: 4rem;
  border-top: 1px solid var(--line);
}
.site-footer a {
  color: var(--ink); border-bottom-color: var(--line);
}
.site-footer a:hover { color: var(--violet); border-bottom-color: var(--violet); }
.footer-grid {
  display: grid; grid-template-columns: 1.3fr 1fr 1fr;
  gap: 2.5rem; padding-bottom: 2rem;
  border-bottom: 1px solid var(--line);
}
@media (max-width: 720px) { .footer-grid { grid-template-columns: 1fr; } }
.footer-brand {
  font-family: var(--font-display); font-size: 1.4rem; font-weight: 600;
  margin-bottom: .5rem; color: var(--ink);
}
.footer-h {
  font-size: .72rem; letter-spacing: .18em; text-transform: uppercase;
  color: var(--cyan); margin-bottom: .8rem; font-weight: 700;
}
.footer-nav { list-style: none; padding: 0; margin: 0; }
.footer-nav li { margin-bottom: .35rem; }
.footer-bottom { padding-top: 1.5rem; text-align: center; font-size: .85rem; color: var(--ink-dim); }

/* ─── Course detail page ─── */
.course-hero {
  padding: clamp(2.5rem, 5vw, 4rem) 0;
}
.course-hero-grid {
  display: grid; grid-template-columns: 2fr 1fr; gap: 2.5rem; align-items: start;
}
@media (max-width: 960px) { .course-hero-grid { grid-template-columns: 1fr; } }
.course-buy-card {
  background: var(--bg-elev); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 1.75rem;
  box-shadow: var(--shadow-lg);
  position: sticky; top: 84px;
}
.course-buy-card .price {
  font-family: var(--font-display); font-size: 2.4rem; font-weight: 600;
  color: var(--cyan); margin: 0 0 .25rem;
}
.course-buy-card .price small {
  font-family: var(--font-sans); font-size: .9rem; color: var(--ink-dim);
  display: block; font-weight: 400; margin-top: .1rem;
}
.course-buy-card ul {
  list-style: none; padding: 0; margin: 1.25rem 0;
}
.course-buy-card ul li {
  padding: .5rem 0 .5rem 1.5rem;
  position: relative;
  color: var(--ink-soft);
  font-size: .94rem;
}
.course-buy-card ul li::before {
  content: '✓';
  position: absolute; left: 0; top: .5rem;
  color: var(--cyan); font-weight: 700;
}

/* Module + lesson list */
.module-list { list-style: none; padding: 0; margin: 2rem 0 0; }
.module {
  background: var(--bg-elev); border: 1px solid var(--line);
  border-radius: var(--radius); margin-bottom: 1rem; overflow: hidden;
}
.module-h {
  padding: 1.1rem 1.25rem;
  display: flex; align-items: center; gap: 1rem;
  background: var(--bg-soft); border-bottom: 1px solid var(--line);
}
.module-num {
  display: inline-grid; place-items: center;
  width: 32px; height: 32px; border-radius: 8px;
  background: linear-gradient(135deg, var(--violet), var(--violet-deep));
  color: #fff; font-weight: 700; font-size: .92rem;
  font-family: var(--font-display);
  flex: none;
}
.module-h h3 { margin: 0; font-size: 1.05rem; }
.lesson-list { list-style: none; padding: 0; margin: 0; }
.lesson-list li {
  display: flex; align-items: center; gap: 1rem;
  padding: .85rem 1.25rem;
  border-bottom: 1px solid var(--line-soft);
  font-size: .96rem;
  color: var(--ink-soft);
}
.lesson-list li:last-child { border-bottom: 0; }
.lesson-list li.locked { color: var(--ink-dim); }
.lesson-list .lesson-icon {
  width: 22px; height: 22px; display: grid; place-items: center;
  font-size: .85rem;
  color: var(--ink-dim);
}
.lesson-list li.complete .lesson-icon { color: var(--ok); }
.lesson-list a {
  color: var(--ink); border: none; flex-grow: 1;
}
.lesson-list a:hover { color: var(--violet); }
.lesson-list .duration {
  font-family: var(--font-mono);
  font-size: .82rem; color: var(--ink-dim);
  background: none; padding: 0;
}

/* Lesson player layout */
.lesson-page { padding: 1.5rem 0 4rem; }
.lesson-layout {
  display: grid; grid-template-columns: minmax(0, 1fr) 320px; gap: 2rem;
}
@media (max-width: 1080px) { .lesson-layout { grid-template-columns: 1fr; } }
.lesson-main { min-width: 0; }
.video-wrap {
  position: relative;
  padding-bottom: 56.25%;
  height: 0;
  background: #000;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--line);
}
.video-wrap iframe {
  position: absolute; inset: 0; width: 100%; height: 100%;
  border: 0;
}
.lesson-notes {
  background: var(--bg-elev); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 1.75rem;
  margin-top: 1.5rem; line-height: 1.7;
}
.lesson-notes h2, .lesson-notes h3 { margin-top: 1.5em; }
.lesson-notes :first-child { margin-top: 0; }
.lesson-notes pre {
  background: var(--bg-soft); padding: 1rem; border-radius: 8px;
  overflow: auto; font-family: var(--font-mono); font-size: .9rem;
}

.lesson-side {
  background: var(--bg-elev); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 1.25rem;
  align-self: start; position: sticky; top: 84px;
}
.lesson-side h4 { font-size: .72rem; letter-spacing: .18em; text-transform: uppercase; color: var(--cyan); margin: 1.25rem 0 .5rem; }
.lesson-side h4:first-child { margin-top: 0; }

/* Progress bar */
.progress {
  height: 6px; background: var(--bg-soft); border-radius: 999px;
  overflow: hidden;
}
.progress-bar {
  height: 100%; background: linear-gradient(90deg, var(--violet), var(--cyan));
  transition: width .3s;
}

/* Community feed */
.community-layout {
  display: grid; grid-template-columns: 220px minmax(0, 1fr) 280px; gap: 2rem;
}
@media (max-width: 1080px) { .community-layout { grid-template-columns: 1fr; } }
@media (max-width: 1080px) { .community-side { display: none; } }
.spaces-nav {
  background: var(--bg-elev); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 1rem;
  align-self: start; position: sticky; top: 84px;
}
.spaces-nav h4 { font-size: .72rem; letter-spacing: .18em; text-transform: uppercase; color: var(--cyan); margin: 0 0 .75rem; }
.spaces-nav ul { list-style: none; padding: 0; margin: 0; }
.spaces-nav li a {
  display: block; padding: .55rem .75rem; border-radius: 6px;
  color: var(--ink-soft); border: none;
  font-size: .94rem;
}
.spaces-nav li a:hover, .spaces-nav li a.active {
  background: var(--violet-soft); color: var(--ink);
}

.post {
  background: var(--bg-elev); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 1.5rem;
  margin-bottom: 1rem;
}
.post-h {
  display: flex; align-items: center; gap: .75rem;
  margin-bottom: .75rem;
  font-size: .88rem; color: var(--ink-soft);
}
.avatar {
  width: 36px; height: 36px; border-radius: 50%;
  background: linear-gradient(135deg, var(--violet), var(--cyan));
  display: grid; place-items: center;
  color: #0B0B14; font-weight: 700; font-size: .92rem;
  font-family: var(--font-display);
  flex: none;
}
.avatar-sm { width: 28px; height: 28px; font-size: .78rem; }
.post-h strong { color: var(--ink); }
.post-body { margin-bottom: .75rem; white-space: pre-wrap; }
.post-meta {
  display: flex; gap: 1.25rem; font-size: .85rem; color: var(--ink-dim);
}
.post-meta button, .post-meta a {
  background: none; border: none; color: var(--ink-dim);
  cursor: pointer; padding: 0; font: inherit;
}
.post-meta button:hover, .post-meta a:hover { color: var(--violet); }
.comment {
  padding: .75rem 0; border-top: 1px solid var(--line-soft);
  display: flex; gap: .65rem; align-items: flex-start;
  font-size: .92rem;
}
.comment .comment-body strong { color: var(--ink); margin-right: .35rem; }

.composer textarea {
  min-height: 80px; resize: vertical;
}

/* Dashboard */
.dash-grid {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.25rem;
}
.dash-card {
  background: var(--bg-elev); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 1.5rem;
}
.dash-card .label {
  font-size: .72rem; letter-spacing: .18em; text-transform: uppercase;
  color: var(--ink-dim); margin: 0 0 .5rem;
}
.dash-card .stat {
  font-family: var(--font-display); font-size: 2rem; font-weight: 600;
  color: var(--ink); margin: 0;
}

/* Quiz */
.quiz-q { background: var(--bg-elev); border: 1px solid var(--line); border-radius: var(--radius); padding: 1.5rem; margin-bottom: 1rem; }
.quiz-q .prompt { font-weight: 600; margin-bottom: 1rem; }
.quiz-choices { list-style: none; padding: 0; margin: 0; display: grid; gap: .5rem; }
.quiz-choices label {
  display: flex; gap: .75rem; padding: .85rem 1rem;
  border: 1px solid var(--line); border-radius: 8px;
  background: var(--bg-soft); cursor: pointer;
  transition: border-color .15s, background .15s;
}
.quiz-choices label:hover { border-color: var(--violet); }
.quiz-choices input { accent-color: var(--violet); }
.quiz-choices label.right { border-color: var(--ok); background: rgba(52,211,153,.08); }
.quiz-choices label.wrong { border-color: var(--err); background: rgba(248,113,113,.08); }

/* Auth pages */
.auth-shell {
  min-height: 70vh; display: grid; place-items: center; padding: 3rem 1rem;
}
.auth-card {
  width: 100%; max-width: 440px;
  background: var(--bg-elev); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 2.25rem;
  box-shadow: var(--shadow-lg);
  position: relative;
}
.auth-card::before {
  content: ''; position: absolute; top: 0; left: 0; right: 0; height: 1px;
  background: linear-gradient(90deg, transparent, var(--violet), var(--cyan), transparent);
}
.auth-card h1 { font-size: 1.8rem; }

/* Strip / stats row */
.strip { background: var(--bg-elev); border-block: 1px solid var(--line); padding: 2.5rem 0; }
.strip-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 2rem; }
@media (max-width: 720px) { .strip-grid { grid-template-columns: 1fr; } }
.strip-num {
  font-family: var(--font-display);
  font-size: clamp(2rem, 4vw, 2.8rem);
  font-weight: 600;
  background: linear-gradient(120deg, var(--violet), var(--cyan));
  -webkit-background-clip: text; background-clip: text;
  color: transparent;
  line-height: 1;
}
.strip .label { color: var(--ink-soft); margin-top: .5rem; font-size: .9rem; }

/* Prose helpers */
.prose { max-width: 38em; }
.prose strong { color: var(--ink); }

/* Utility */
.stack > * + * { margin-top: 1rem; }
.row-end { display: flex; justify-content: flex-end; }
.hr {
  border: 0; height: 1px; background: var(--line); margin: 1.5rem 0;
}