@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@400;500;600;700;800&family=JetBrains+Mono:wght@400;600&display=swap');

:root {
  --bg-0: #061018;
  --bg-1: #0c1b27;
  --bg-2: #112839;
  --card: rgba(9, 27, 40, 0.84);
  --line: rgba(140, 185, 202, 0.32);
  --text: #ebf5ff;
  --muted: #9eb7c8;
  --accent: #59d8b3;
  --accent-2: #ffb66a;
  --danger: #ff7d7d;
  --ok: #79df95;
  --radius: 16px;
  --shadow: 0 18px 45px rgba(0, 0, 0, 0.3);
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  min-height: 100vh;
  color: var(--text);
  font-family: 'Outfit', 'Segoe UI', sans-serif;
  background:
    radial-gradient(circle at 12% 2%, rgba(89, 216, 179, 0.14), transparent 32%),
    radial-gradient(circle at 92% 0%, rgba(255, 182, 106, 0.11), transparent 38%),
    linear-gradient(180deg, var(--bg-0), var(--bg-1) 42%, var(--bg-2));
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: -1;
  opacity: 0.5;
  background-image:
    radial-gradient(circle at 50% 50%, rgba(89, 216, 179, 0.08), transparent 55%),
    repeating-linear-gradient(0deg, rgba(140, 185, 202, 0.08) 0, rgba(140, 185, 202, 0.08) 1px, transparent 1px, transparent 28px),
    repeating-linear-gradient(90deg, rgba(140, 185, 202, 0.06) 0, rgba(140, 185, 202, 0.06) 1px, transparent 1px, transparent 28px);
  mask-image: radial-gradient(circle at 50% 12%, black 0, black 55%, transparent 78%);
}

.bg-canvas {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  opacity: 0.38;
}

.shell {
  width: min(1240px, 94vw);
  margin: 0 auto;
  padding: 22px 0 48px;
}

.topbar {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(8px);
  background: rgba(7, 16, 24, 0.88);
  border-bottom: 1px solid rgba(140, 185, 202, 0.2);
}

.topbar-inner {
  width: min(1240px, 94vw);
  margin: 0 auto;
  padding: 10px 0;
  display: flex;
  gap: 12px;
  align-items: center;
  justify-content: space-between;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  letter-spacing: 0.01em;
}

.brand-dot {
  width: 12px;
  height: 12px;
  border-radius: 999px;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  box-shadow: 0 0 0 4px rgba(89, 216, 179, 0.15);
}

.brand-mark {
  width: 22px;
  height: 22px;
  display: block;
  border-radius: 8px;
}

.nav {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.nav-toggle {
  display: none;
  width: auto;
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 8px 12px;
  background: rgba(8, 20, 31, 0.78);
  color: var(--text);
  font-weight: 800;
  letter-spacing: 0.01em;
  cursor: pointer;
  align-items: center;
  gap: 10px;
}

.nav-backdrop {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 45;
  background: rgba(5, 12, 18, 0.62);
  backdrop-filter: blur(10px);
}

.nav a {
  text-decoration: none;
  color: var(--text);
  font-size: 0.86rem;
  font-weight: 600;
  padding: 8px 11px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(8, 20, 31, 0.78);
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.nav-icon {
  width: 14px;
  height: 14px;
  opacity: 0.9;
}

.nav a.active {
  border-color: rgba(89, 216, 179, 0.6);
  color: #dffcf4;
}

@media (max-width: 980px) {
  .topbar-inner {
    padding: 12px 0;
  }

  .nav-toggle {
    display: none;
  }

  .nav {
    display: flex;
  }

  /* If JS is working, we enhance mobile nav into an overlay. If JS fails, keep the nav visible. */
  body.nav-enhanced .nav-toggle {
    display: inline-flex;
  }

  body.nav-enhanced .nav {
    display: none;
  }

  body.nav-enhanced.nav-open .nav-backdrop {
    display: block;
  }

  body.nav-enhanced.nav-open .nav {
    display: flex;
    position: fixed;
    left: 12px;
    right: 12px;
    top: 72px;
    z-index: 60;
    padding: 12px;
    flex-direction: column;
    align-items: stretch;
    background: rgba(7, 16, 24, 0.95);
    border: 1px solid rgba(140, 185, 202, 0.28);
    border-radius: 18px;
    box-shadow: 0 30px 80px rgba(0, 0, 0, 0.55);
    max-height: calc(100vh - 92px);
    overflow: auto;
  }

  body.nav-enhanced.nav-open .nav a {
    justify-content: flex-start;
    width: 100%;
  }
}

.hero, .panel {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--card);
  box-shadow: var(--shadow);
  position: relative;
  overflow: hidden;
}

.panel.pad {
  padding: 12px;
}

.links {
  margin-top: 8px;
  color: var(--muted);
  font-size: 0.9rem;
}

.links a {
  color: #8ee7d2;
  text-decoration: none;
  border-bottom: 1px solid rgba(140, 185, 202, 0.28);
}

.links a:hover {
  border-bottom-color: rgba(255, 182, 106, 0.55);
}

.hero::before,
.panel::before {
  content: "";
  position: absolute;
  inset: -1px;
  pointer-events: none;
  opacity: 0.35;
  background:
    radial-gradient(circle at 18% 16%, rgba(89, 216, 179, 0.18), transparent 42%),
    radial-gradient(circle at 82% 18%, rgba(255, 182, 106, 0.15), transparent 48%);
}

.hero {
  padding: 22px;
  display: grid;
  gap: 14px;
  margin-top: 10px;
}

.hero-split {
  grid-template-columns: 1.15fr 0.85fr;
  align-items: center;
  gap: 18px;
  overflow: hidden;
}

.hero-copy {
  display: grid;
  gap: 12px;
}

.kicker {
  display: inline-flex;
  gap: 10px;
  align-items: center;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  font-size: 0.74rem;
  color: rgba(235, 245, 255, 0.72);
}

.kicker::before {
  content: "";
  width: 10px;
  height: 10px;
  border-radius: 999px;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  box-shadow: 0 0 0 6px rgba(89, 216, 179, 0.12);
}

.hero-tagline {
  font-weight: 800;
  letter-spacing: 0.02em;
  color: rgba(235, 245, 255, 0.82);
}

.hero-graphic {
  position: relative;
  border-radius: 18px;
  border: 1px solid rgba(140, 185, 202, 0.22);
  background: rgba(7, 17, 26, 0.55);
  box-shadow: 0 24px 65px rgba(0, 0, 0, 0.35);
  overflow: hidden;
}

.hero-graphic.hero-media {
  min-height: 320px;
}

.hero-graphic::after {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 30% 18%, rgba(89, 216, 179, 0.16), transparent 45%),
    radial-gradient(circle at 78% 22%, rgba(255, 182, 106, 0.13), transparent 52%);
  pointer-events: none;
}

.hero-graphic img {
  width: 100%;
  height: auto;
  display: block;
  transform: translateZ(0);
}

.hero-graphic.hero-media img {
  height: 100%;
  object-fit: cover;
}

.hero h1 {
  margin: 0;
  font-size: clamp(1.8rem, 4.5vw, 3.1rem);
  line-height: 1.07;
}

.hero p {
  margin: 0;
  color: var(--muted);
  max-width: 88ch;
}

.metrics {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 10px;
}

.metric {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 10px;
  background: rgba(8, 19, 29, 0.8);
}

.metric .label {
  color: var(--muted);
  font-size: 0.79rem;
}

.metric .value {
  font-size: 1.2rem;
  font-weight: 700;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 11px;
}

.track-grid {
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
}

.track-card {
  text-decoration: none;
  color: var(--text);
  border: 1px solid rgba(140, 185, 202, 0.3);
  border-radius: 16px;
  background: linear-gradient(180deg, rgba(7, 17, 26, 0.86), rgba(7, 17, 26, 0.74));
  padding: 14px;
  box-shadow: 0 18px 55px rgba(0, 0, 0, 0.25);
  position: relative;
  overflow: hidden;
  transition: transform 180ms ease, border-color 180ms ease, background 180ms ease;
  display: block;
}

.track-card::before {
  content: "";
  position: absolute;
  inset: -1px;
  opacity: 0.28;
  background:
    radial-gradient(circle at 20% 18%, rgba(89, 216, 179, 0.22), transparent 48%),
    radial-gradient(circle at 82% 28%, rgba(255, 182, 106, 0.18), transparent 55%);
  pointer-events: none;
}

.track-card:hover {
  transform: translateY(-2px);
  border-color: rgba(89, 216, 179, 0.65);
  background: linear-gradient(180deg, rgba(7, 17, 26, 0.94), rgba(7, 17, 26, 0.82));
}

.track-top {
  display: flex;
  gap: 12px;
  align-items: center;
  position: relative;
}

.track-ic {
  width: 28px;
  height: 28px;
  flex: 0 0 auto;
  opacity: 0.92;
}

.track-title {
  font-weight: 850;
  letter-spacing: 0.01em;
}

.track-sub {
  margin-top: 10px;
  color: rgba(235, 245, 255, 0.7);
  font-size: 0.92rem;
  position: relative;
}

.topic-map-panel {
  display: grid;
  gap: 10px;
}

.topic-map {
  width: 100%;
  height: 340px;
  display: block;
  border-radius: 16px;
  border: 1px solid rgba(140, 185, 202, 0.28);
  background: rgba(7, 17, 26, 0.65);
  overflow: hidden;
}

.topic-map .map-line {
  stroke: rgba(140, 185, 202, 0.35);
  stroke-width: 1.2;
}

.topic-map .map-node {
  fill: rgba(89, 216, 179, 0.16);
  stroke: rgba(89, 216, 179, 0.55);
  stroke-width: 1.2;
}

.topic-map .map-node.hot {
  fill: rgba(255, 182, 106, 0.16);
  stroke: rgba(255, 182, 106, 0.75);
}

.topic-map .map-label {
  fill: rgba(235, 245, 255, 0.88);
  font-size: 12px;
  font-family: 'JetBrains Mono', monospace;
  letter-spacing: 0.01em;
}

.topic-map a:hover .map-node,
.topic-map a:focus .map-node {
  fill: rgba(89, 216, 179, 0.26);
  stroke: rgba(89, 216, 179, 0.9);
}

.topic-map a:hover .map-node.hot,
.topic-map a:focus .map-node.hot {
  fill: rgba(255, 182, 106, 0.24);
  stroke: rgba(255, 182, 106, 0.95);
}

.section {
  margin-top: 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(10, 25, 37, 0.78);
  padding: 16px;
}

.section h2 {
  margin: 0 0 8px;
  font-size: 1.35rem;
}

.section p { margin: 0 0 10px; color: var(--muted); }

.card {
  border: 1px solid var(--line);
  border-radius: 12px;
  background: rgba(7, 17, 26, 0.83);
  padding: 11px;
  transition: transform 160ms ease, border-color 160ms ease, background 160ms ease;
  will-change: transform;
  overflow-wrap: anywhere;
  word-break: break-word;
}

.card:hover {
  transform: translateY(-2px);
  border-color: rgba(89, 216, 179, 0.55);
  background: rgba(7, 17, 26, 0.92);
}

.feature-card {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 12px;
  align-items: start;
}

.feature-icon {
  width: 60px;
  height: 60px;
  border-radius: 18px;
  border: 1px solid rgba(140, 185, 202, 0.28);
  background: rgba(8, 19, 29, 0.6);
  padding: 6px;
}

.card h3 { margin: 0 0 6px; font-size: 1rem; }
.card p { margin: 0; color: var(--muted); font-size: 0.92rem; }

.card-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 8px;
}

.card-badges .chip {
  margin: 0;
}

.card-title {
  display: flex;
  align-items: center;
  gap: 8px;
}

.card-title .icon {
  margin-right: 0;
  flex: 0 0 auto;
}

.card-sub {
  margin: 0 0 8px;
}

.card-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 10px;
}

.card-actions .pill {
  padding: 7px 10px;
  font-size: 0.82rem;
}

.card-actions .pill:last-child {
  border-color: rgba(89, 216, 179, 0.62);
}

.chip {
  display: inline-block;
  margin: 0 6px 6px 0;
  font-size: 0.72rem;
  padding: 4px 8px;
  border-radius: 999px;
  border: 1px solid var(--line);
  color: var(--muted);
  background: rgba(8, 20, 31, 0.55);
}

.icon {
  width: 18px;
  height: 18px;
  vertical-align: -3px;
  margin-right: 6px;
  opacity: 0.92;
}

.row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 11px;
}

.usb-file {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
}

.usb-path {
  flex: 1 1 280px;
  min-width: 0;
}

.usb-path-link {
  color: inherit;
  text-decoration: none;
  border-bottom: 1px solid rgba(140, 185, 202, 0.28);
}

.usb-path-link:hover {
  border-bottom-color: rgba(255, 182, 106, 0.55);
}

.usb-path code {
  white-space: normal;
  overflow-wrap: anywhere;
  word-break: break-word;
}

.page-usb .card summary {
  cursor: pointer;
}

.page-usb .usb-file {
  align-items: flex-start;
}

.page-usb .usb-path-link,
.page-usb .usb-path,
.page-usb .meta {
  overflow-wrap: anywhere;
  word-break: break-word;
}

.controls {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 10px;
  margin-bottom: 10px;
}

input, select, button, textarea {
  width: 100%;
  border: 1px solid #3f6274;
  border-radius: 10px;
  padding: 10px 11px;
  background: #0a1a27;
  color: var(--text);
  font-family: 'Outfit', sans-serif;
}

textarea { min-height: 130px; resize: vertical; }

button {
  cursor: pointer;
  border-color: rgba(89, 216, 179, 0.58);
  background: linear-gradient(180deg, rgba(20, 81, 82, 0.9), rgba(16, 58, 67, 0.92));
  font-weight: 700;
}

a { color: #8ee7d2; }

.meta {
  color: var(--muted);
  font-size: 0.82rem;
  font-family: 'JetBrains Mono', monospace;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.hero-actions a {
  text-decoration: none;
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 9px 13px;
  background: rgba(8, 20, 31, 0.75);
  transition: transform 140ms ease, border-color 140ms ease;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.hero-actions a:first-child {
  border-color: rgba(89, 216, 179, 0.6);
  background: linear-gradient(180deg, rgba(20, 81, 82, 0.9), rgba(16, 58, 67, 0.92));
}

.hero-actions a:hover {
  transform: translateY(-1px);
  border-color: rgba(255, 182, 106, 0.55);
}

.banner {
  border: 1px solid rgba(89, 216, 179, 0.45);
  background: rgba(9, 48, 46, 0.45);
  border-radius: 12px;
  padding: 10px 12px;
}

.pillrow {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.pill {
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 7px 11px;
  background: rgba(8, 20, 31, 0.75);
  color: var(--text);
  text-decoration: none;
  font-size: 0.82rem;
  cursor: pointer;
  width: auto;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  max-width: 100%;
  white-space: normal;
  overflow-wrap: anywhere;
}

.tabs {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 10px;
}

.tab {
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 7px 11px;
  background: rgba(8, 20, 31, 0.75);
  color: var(--text);
  cursor: pointer;
  width: auto;
}

.tab.active {
  border-color: rgba(89, 216, 179, 0.6);
  color: #dffcf4;
}

/* --- Interactive course --- */
.course-layout {
  display: grid;
  grid-template-columns: 360px 1fr;
  gap: 12px;
  align-items: start;
}

.course-track-list {
  display: grid;
  gap: 10px;
  margin-top: 10px;
}

.course-track-btn {
  text-align: left;
  border: 1px solid rgba(140, 185, 202, 0.28);
  border-radius: 14px;
  background: rgba(7, 17, 26, 0.84);
  padding: 10px 12px;
  font-weight: 750;
  transition: transform 160ms ease, border-color 160ms ease, background 160ms ease;
}

.course-track-btn:hover {
  transform: translateY(-1px);
  border-color: rgba(89, 216, 179, 0.55);
  background: rgba(7, 17, 26, 0.92);
}

.course-track-btn.active {
  border-color: rgba(89, 216, 179, 0.7);
}

.course-track-title {
  font-weight: 850;
  margin-bottom: 2px;
}

.course-track-kv {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 6px;
}

.progress-select {
  width: auto;
  min-width: 170px;
}

.checklist {
  display: grid;
  gap: 8px;
  margin-top: 10px;
}

.checkitem {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  padding: 8px 10px;
  border: 1px solid rgba(140, 185, 202, 0.22);
  border-radius: 12px;
  background: rgba(8, 20, 31, 0.5);
}

.checkitem input[type="checkbox"] {
  width: auto;
  margin: 2px 0 0;
  padding: 0;
  border: none;
  border-radius: 6px;
  background: transparent;
  accent-color: var(--accent);
}

.checkitem span {
  flex: 1;
}

.kv { display: flex; justify-content: space-between; gap: 8px; }
.kv .k { color: var(--muted); }

.bad { color: var(--danger); }
.warn { color: var(--accent-2); }
.ok { color: var(--ok); }

footer {
  margin-top: 20px;
  color: var(--muted);
  font-size: 0.84rem;
  text-align: center;
}

.tutor-widget {
  position: fixed;
  right: 16px;
  bottom: 16px;
  z-index: 80;
  width: min(420px, 92vw);
}

.tutor-widget::before {
  content: "";
  position: absolute;
  inset: -34px -22px;
  z-index: -1;
  background:
    radial-gradient(circle at 30% 30%, rgba(89, 216, 179, 0.22), transparent 55%),
    radial-gradient(circle at 75% 25%, rgba(255, 182, 106, 0.18), transparent 58%);
  filter: blur(18px);
  opacity: 0.7;
  pointer-events: none;
}

.tutor-collapsed {
  padding: 12px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 10px;
  cursor: pointer;
  max-height: 120px;
  opacity: 1;
  transform: translateY(0);
  transition: max-height 180ms ease, opacity 180ms ease, transform 180ms ease, padding 180ms ease, border-width 180ms ease;
}

.tutor-collapsed-copy {
  display: flex;
  align-items: center;
  gap: 12px;
}

.tutor-collapsed-icon {
  width: 42px;
  height: 42px;
  border-radius: 999px;
  border: 1px solid rgba(140, 185, 202, 0.28);
  background: linear-gradient(135deg, rgba(89, 216, 179, 0.24), rgba(255, 182, 106, 0.18));
  display: grid;
  place-items: center;
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.32);
}

.tutor-widget.attention .tutor-collapsed {
  animation: tutorPulse 1.8s ease-in-out infinite;
}

@keyframes tutorPulse {
  0% { transform: translateY(0); box-shadow: 0 18px 45px rgba(0, 0, 0, 0.28); }
  50% { transform: translateY(-2px); box-shadow: 0 24px 70px rgba(0, 0, 0, 0.38); }
  100% { transform: translateY(0); box-shadow: 0 18px 45px rgba(0, 0, 0, 0.28); }
}

.tutor-label {
  font-weight: 800;
  letter-spacing: 0.02em;
}

.tutor-btn {
  width: auto;
  padding: 8px 12px;
  border-radius: 999px;
}

.tutor-btn.secondary {
  border-color: var(--line);
  background: rgba(8, 20, 31, 0.75);
}

.tutor-panel {
  padding: 12px;
  max-height: 0;
  opacity: 0;
  transform: translateY(10px) scale(0.985);
  overflow: hidden;
  pointer-events: none;
  transition: max-height 220ms ease, opacity 220ms ease, transform 220ms ease;
}

.tutor-widget.open .tutor-panel {
  max-height: 72vh;
  opacity: 1;
  transform: translateY(0) scale(1);
  overflow: auto;
  pointer-events: auto;
}

.tutor-widget.open .tutor-collapsed {
  max-height: 0;
  opacity: 0;
  transform: translateY(10px) scale(0.985);
  padding: 0;
  border-width: 0;
  pointer-events: none;
}

.tutor-top {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 10px;
}

.tutor-divider {
  height: 1px;
  background: rgba(140, 185, 202, 0.25);
  margin: 10px 0;
}

.tutor-grid {
  margin-top: 8px;
}

.check {
  width: auto;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 10px 11px;
  border: 1px solid #3f6274;
  border-radius: 10px;
  background: #0a1a27;
  color: var(--text);
  font-family: 'Outfit', sans-serif;
  font-weight: 600;
}

.check input {
  width: auto;
  margin: 0;
  accent-color: var(--accent);
}

.chat {
  margin-top: 10px;
  border: 1px solid rgba(140, 185, 202, 0.28);
  border-radius: var(--radius);
  background: rgba(7, 17, 26, 0.72);
  overflow: hidden;
}

.chat-log {
  max-height: 56vh;
  overflow: auto;
  padding: 12px;
  display: grid;
  gap: 10px;
}

.bubble-row {
  display: flex;
}

.bubble-row.user {
  justify-content: flex-end;
}

.bubble-row.assistant {
  justify-content: flex-start;
}

.bubble {
  max-width: min(840px, 92%);
  border: 1px solid rgba(140, 185, 202, 0.28);
  border-radius: 16px;
  padding: 10px 12px;
  white-space: pre-wrap;
  line-height: 1.35;
}

.bubble.user {
  background: rgba(12, 41, 43, 0.72);
  border-color: rgba(89, 216, 179, 0.35);
}

.bubble.assistant {
  background: rgba(9, 27, 40, 0.84);
}

.vision-item.user {
  border-color: rgba(89, 216, 179, 0.38);
}

.vision-item.assistant {
  border-color: rgba(140, 185, 202, 0.32);
}

.vision-preview {
  margin: 10px 0;
  border-radius: 14px;
  overflow: hidden;
  border: 1px solid rgba(140, 185, 202, 0.22);
  background: rgba(7, 17, 26, 0.65);
}

.vision-preview img {
  width: 100%;
  height: auto;
  display: block;
}

.chat-compose {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 10px;
  padding: 12px;
  border-top: 1px solid rgba(140, 185, 202, 0.22);
  background: rgba(8, 19, 29, 0.8);
}

.chat-compose textarea {
  min-height: 84px;
}

.chat-compose button {
  width: auto;
  align-self: start;
  padding: 10px 16px;
}

.cmdk {
  position: fixed;
  inset: 0;
  z-index: 100;
  display: none;
}

.cmdk.open {
  display: block;
}

.cmdk-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(5, 12, 18, 0.58);
  backdrop-filter: blur(10px);
}

.cmdk-panel {
  position: absolute;
  left: 50%;
  top: 8vh;
  transform: translateX(-50%);
  width: min(860px, 94vw);
  padding: 14px;
}

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

.cmdk-title {
  font-weight: 800;
  letter-spacing: 0.01em;
}

.cmdk-close {
  width: auto;
  padding: 7px 12px;
  border-radius: 999px;
  border-color: rgba(140, 185, 202, 0.28);
  background: rgba(8, 20, 31, 0.75);
  font-weight: 700;
}

.cmdk-input input {
  font-size: 1.05rem;
  padding: 12px 14px;
  border-radius: 14px;
}

.cmdk-list {
  margin-top: 10px;
  display: grid;
  gap: 8px;
}

.cmdk-item {
  text-align: left;
  border: 1px solid rgba(140, 185, 202, 0.28);
  border-radius: 14px;
  background: rgba(7, 17, 26, 0.84);
  padding: 10px 12px;
  display: grid;
  grid-template-columns: auto 1fr auto;
  gap: 12px;
  cursor: pointer;
  transition: transform 160ms ease, border-color 160ms ease, background 160ms ease;
}

.cmdk-item:hover {
  transform: translateY(-1px);
  border-color: rgba(89, 216, 179, 0.55);
  background: rgba(7, 17, 26, 0.92);
}

.cmdk-ic {
  width: 22px;
  height: 22px;
  opacity: 0.92;
  margin-top: 2px;
}

.cmdk-item-title {
  font-weight: 750;
  margin-bottom: 2px;
}

.cmdk-item-sub {
  color: var(--muted);
  font-size: 0.84rem;
  font-family: 'JetBrains Mono', monospace;
}

.cmdk-kbd {
  color: rgba(235, 245, 255, 0.82);
  border: 1px solid rgba(140, 185, 202, 0.24);
  border-radius: 10px;
  padding: 3px 8px;
  background: rgba(8, 19, 29, 0.72);
  font-size: 0.78rem;
  font-family: 'JetBrains Mono', monospace;
}

@media (max-width: 880px) {
  .row { grid-template-columns: 1fr; }
  .course-layout { grid-template-columns: 1fr; }
  .topbar-inner { align-items: flex-start; flex-direction: column; }
  .hero-split { grid-template-columns: 1fr; }
}

@media (prefers-reduced-motion: reduce) {
  .card, .hero-actions a { transition: none; }
  .bg-canvas { display: none; }
}