:root {
  --bg: #030712;
  --bg-2: #06121f;
  --panel: rgba(8, 20, 34, 0.72);
  --panel-strong: rgba(7, 18, 31, 0.92);
  --line: rgba(166, 230, 255, 0.18);
  --line-strong: rgba(103, 216, 255, 0.34);
  --text: #f7fbff;
  --muted: #a9bdd0;
  --cyan: #22d6ff;
  --blue: #2764ff;
  --aqua: #19f4df;
  --pink: #f5a3ff;
  --warm: #ffd56a;
  --shadow: 0 30px 90px rgba(0, 0, 0, 0.42);
  --radius: 22px;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--text);
  background:
    radial-gradient(circle at 48% -10%, rgba(34, 214, 255, 0.24), transparent 34rem),
    radial-gradient(circle at 78% 10%, rgba(245, 163, 255, 0.12), transparent 30rem),
    linear-gradient(180deg, #030712 0%, #06111d 48%, #02050b 100%);
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  background:
    linear-gradient(rgba(255,255,255,0.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.018) 1px, transparent 1px);
  background-size: 42px 42px;
  mask-image: radial-gradient(circle at 50% 20%, black, transparent 74%);
}

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

.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding: 14px max(18px, calc((100vw - 1180px) / 2));
  background: rgba(3, 7, 18, 0.78);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(22px) saturate(160%);
}

.brand {
  display: flex;
  align-items: center;
  gap: 14px;
  font-weight: 850;
  letter-spacing: 0;
}

.brand-logo {
  display: block;
  width: 96px;
  height: auto;
}

.brand-title {
  color: var(--muted);
  font-size: 0.9rem;
  font-weight: 780;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  border-radius: 13px;
  background:
    radial-gradient(circle at 35% 30%, #fff, transparent 28%),
    radial-gradient(circle at 55% 58%, var(--aqua), var(--blue) 50%, transparent 70%);
  box-shadow: 0 0 28px rgba(34, 214, 255, 0.58);
}

.nav {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 5px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.035);
}

.nav a,
.nav span {
  padding: 9px 14px;
  border-radius: 999px;
  color: var(--muted);
  font-size: 0.9rem;
  font-weight: 760;
}

.nav a[aria-current="page"],
.nav a:hover,
.nav span[aria-current="page"] {
  color: var(--text);
  background: rgba(34, 214, 255, 0.12);
}

.hero {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(320px, 0.9fr);
  gap: 42px;
  align-items: center;
  min-height: 700px;
  padding: 84px max(20px, calc((100vw - 1180px) / 2)) 70px;
  overflow: hidden;
}

.hero::after {
  content: "";
  position: absolute;
  inset: 12% -8% auto auto;
  width: 44vw;
  height: 44vw;
  max-width: 620px;
  max-height: 620px;
  background: radial-gradient(circle, rgba(25, 244, 223, 0.26), rgba(39, 100, 255, 0.16) 38%, transparent 68%);
  filter: blur(34px);
  opacity: 0.8;
}

.hero-copy,
.hero-media {
  position: relative;
  z-index: 1;
}

.kicker {
  margin: 0 0 18px;
  color: var(--cyan);
  font-size: 0.82rem;
  font-weight: 850;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

h1,
h2,
h3 {
  margin: 0;
  letter-spacing: 0;
}

h1 {
  max-width: 820px;
  font-size: clamp(3.1rem, 7vw, 6.8rem);
  line-height: 0.92;
}

h2 {
  font-size: clamp(2rem, 4vw, 4rem);
  line-height: 1;
}

h3 {
  font-size: 1.26rem;
  line-height: 1.2;
}

.lead {
  max-width: 700px;
  margin: 24px 0 0;
  color: #d9e9f6;
  font-size: clamp(1.08rem, 1.8vw, 1.34rem);
  line-height: 1.6;
}

.button-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 32px;
}

.button {
  display: inline-flex;
  min-height: 48px;
  align-items: center;
  justify-content: center;
  padding: 0 18px;
  border-radius: 999px;
  border: 1px solid var(--line-strong);
  font-weight: 850;
}

.button.primary {
  color: #00111a;
  background: linear-gradient(135deg, #ffffff, #8eeeff 42%, #58a7ff);
  box-shadow: 0 0 44px rgba(34, 214, 255, 0.32);
}

.button.ghost {
  color: var(--text);
  background: rgba(255,255,255,0.05);
}

.hero-card,
.panel,
.prompt-card,
.mode-card,
.step-card,
.mistake-card {
  border: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(11, 26, 45, 0.82), rgba(5, 12, 22, 0.68));
  box-shadow: var(--shadow);
  backdrop-filter: blur(18px);
}

.hero-card {
  border-radius: 32px;
  overflow: hidden;
}

.hero-card img {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

.hero-card .card-body {
  padding: 24px;
}

.metric-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin-top: 24px;
}

.metric {
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: rgba(255,255,255,0.035);
}

.metric strong {
  display: block;
  color: var(--text);
  font-size: 1.45rem;
}

.metric span,
.muted {
  color: var(--muted);
}

.section {
  padding: 78px max(20px, calc((100vw - 1180px) / 2));
}

.section.alt {
  background: linear-gradient(180deg, rgba(39, 100, 255, 0.06), rgba(25, 244, 223, 0.035));
  border-block: 1px solid var(--line);
}

.section-head {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 28px;
}

.section-head p {
  max-width: 560px;
  margin: 0;
  color: var(--muted);
  line-height: 1.7;
}

.grid {
  display: grid;
  gap: 16px;
}

.grid.cols-2 {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.grid.cols-3 {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.panel,
.mode-card,
.step-card,
.mistake-card {
  border-radius: var(--radius);
  padding: 24px;
}

.panel p,
.mode-card p,
.step-card p,
.mistake-card p {
  margin: 12px 0 0;
  color: var(--muted);
  line-height: 1.65;
}

.number {
  display: inline-grid;
  place-items: center;
  width: 42px;
  height: 42px;
  margin-bottom: 18px;
  border-radius: 15px;
  color: #00111a;
  background: linear-gradient(135deg, #fff, var(--cyan));
  font-weight: 900;
}

.formula {
  overflow-x: auto;
  margin-top: 22px;
  padding: 22px;
  border: 1px solid var(--line-strong);
  border-radius: 18px;
  color: #dff8ff;
  background: rgba(0, 7, 15, 0.72);
  font-family: "SFMono-Regular", Consolas, monospace;
  line-height: 1.7;
}

.timeline {
  display: grid;
  gap: 14px;
  margin-top: 26px;
}

.timeline-item {
  display: grid;
  grid-template-columns: 120px 1fr;
  gap: 18px;
  align-items: start;
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: 20px;
  background: rgba(255,255,255,0.035);
}

.time {
  color: var(--cyan);
  font-weight: 900;
}

.prompt-card {
  margin-bottom: 30px;
  border-radius: 30px;
  overflow: hidden;
}

.prompt-media {
  display: block;
  width: 100%;
  max-height: 560px;
  object-fit: cover;
  background: #000;
}

.prompt-body {
  padding: 28px;
}

.prompt-body pre {
  max-height: 640px;
  overflow: auto;
  margin: 20px 0 0;
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: 18px;
  color: #e9f8ff;
  background: rgba(0, 7, 15, 0.78);
  white-space: pre-wrap;
  line-height: 1.6;
  font-size: 0.94rem;
}

.tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 16px;
}

.tag {
  padding: 7px 10px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: #ccefff;
  background: rgba(34, 214, 255, 0.08);
  font-size: 0.82rem;
  font-weight: 800;
}

.footer {
  padding: 38px max(20px, calc((100vw - 1180px) / 2));
  color: var(--muted);
  border-top: 1px solid var(--line);
}

.footer strong {
  color: var(--text);
}

.reference-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 24px;
  background: var(--line);
}

.reference-cell {
  min-height: 230px;
  padding: 28px;
  background: rgba(4, 13, 24, 0.86);
}

.reference-cell h3 {
  color: var(--cyan);
}

.reference-cell p {
  margin: 12px 0 0;
  color: var(--muted);
  line-height: 1.65;
}

.mode-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
}

.mode-card {
  min-height: 190px;
}

.symptom-list {
  display: grid;
  gap: 12px;
}

.symptom {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
  gap: 16px;
  align-items: center;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: rgba(255,255,255,0.035);
}

.symptom b {
  color: var(--text);
}

.symptom span {
  color: var(--cyan);
  font-weight: 900;
}

@media (max-width: 860px) {
  .topbar {
    align-items: flex-start;
    flex-direction: column;
  }

  .nav {
    width: 100%;
    overflow-x: auto;
    justify-content: flex-start;
  }

  .hero {
    grid-template-columns: 1fr;
    min-height: auto;
    padding-top: 58px;
  }

  .section-head {
    align-items: start;
    flex-direction: column;
  }

  .grid.cols-2,
  .grid.cols-3,
  .metric-grid,
  .reference-grid,
  .mode-grid {
    grid-template-columns: 1fr;
  }

  .timeline-item {
    grid-template-columns: 1fr;
  }

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

@media print {
  html {
    scroll-behavior: auto;
  }

  body {
    background: #030712 !important;
    print-color-adjust: exact;
    -webkit-print-color-adjust: exact;
  }

  .topbar {
    position: static;
  }

  .hero {
    min-height: auto;
  }

  .prompt-body pre {
    max-height: none;
    overflow: visible;
    break-inside: auto;
  }

  .prompt-card,
  .panel,
  .step-card,
  .mode-card,
  .mistake-card,
  .timeline-item,
  .reference-grid,
  .symptom {
    break-inside: avoid;
  }

  .prompt-card {
    break-inside: auto;
  }
}