/* ── Reset & base ───────────────────────────────────────── */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --bg: #0f0f0f;
  --accent-rgb: 201 162 39;
  --bg-surface: #1a1a1a;
  --text: #f5f0e8;
  --text-muted: #a89f8f;
  --accent: #c9a227;
  --accent-hover: #d4a843;
  --accent-glow: rgb(var(--accent-rgb) / 0.15);
  --card-bg: rgba(255, 255, 255, 0.04);
  --card-border: rgb(var(--accent-rgb) / 0.12);
  --card-border-hover: rgb(var(--accent-rgb) / 0.4);
  --shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
  --radius: 12px;
  --font-display: 'Cinzel', Georgia, serif;
  --font-body: 'DM Sans', system-ui, sans-serif;
}

html {
  overflow-x: hidden;
}

body {
  background-color: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.6;
  min-height: 100vh;
  padding-bottom: 1.5rem;
}

.container {
  max-width: 920px;
  margin: 0 auto;
}

a {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 2px;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--accent-hover);
  opacity: 1;
}

/* ── Animations ─────────────────────────────────────────── */
@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(24px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ── Background grain overlay ──────────────────────────── */
.bg-grain {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 9999;
  opacity: 0.035;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)'/%3E%3C/svg%3E");
  background-repeat: repeat;
  background-size: 256px 256px;
}

/* ── GitHub link ───────────────────────────────────────── */
.github-link {
  position: fixed;
  top: 1.25rem;
  right: 1.5rem;
  z-index: 100;
  color: var(--text-muted);
  text-decoration: none;
  transition: color 0.2s ease, transform 0.2s ease;
  opacity: 0.7;
}

.github-link:hover {
  color: var(--text);
  opacity: 1;
  transform: scale(1.1);
}

/* ── Hero ───────────────────────────────────────────────── */
.hero {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 1.25rem 1.5rem 1rem;
  text-align: center;
}

.hero-glow {
  position: absolute;
  width: 600px;
  height: 400px;
  border-radius: 50%;
  background: radial-gradient(ellipse, rgb(var(--accent-rgb) / 0.08) 0%, transparent 70%);
  pointer-events: none;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -40%);
  z-index: 0;
}

.hero-brand {
  display: flex;
  align-items: center;
  gap: 1.25rem;
  position: relative;
  z-index: 1;
  animation: fadeUp 0.8s ease-out both;
}

.hero-icon {
  width: 72px;
  height: 72px;
  flex-shrink: 0;
  filter: drop-shadow(0 0 20px rgb(var(--accent-rgb) / 0.3));
}

.hero-title {
  font-family: var(--font-display);
  font-size: clamp(2.5rem, 8vw, 4.5rem);
  font-weight: 900;
  letter-spacing: -0.02em;
  line-height: 1.1;
  color: var(--text);
  text-shadow: 0 0 40px rgb(var(--accent-rgb) / 0.15);
}

.hero-screenshot-wrapper {
  perspective: 1200px;
  margin-top: 1rem;
  position: relative;
  z-index: 1;
  animation: fadeUp 0.8s ease-out 0.4s both;
}

.hero-screenshot {
  width: 100%;
  max-width: 620px;
  height: auto;
  border-radius: var(--radius);
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5), 0 0 0 1px rgb(var(--accent-rgb) / 0.1);
  display: block;
  transform: rotateX(2deg);
  transition: transform 0.4s ease, box-shadow 0.4s ease;
}

.hero-screenshot:hover {
  transform: rotateX(0deg);
  box-shadow: 0 30px 80px rgba(0, 0, 0, 0.6), 0 0 0 1px rgb(var(--accent-rgb) / 0.2);
}

/* ── Downloads ──────────────────────────────────────────── */
.downloads {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  padding: 0.75rem 1.5rem;
  flex-wrap: wrap;
  animation: fadeUp 0.6s ease-out 0.35s both;
}

.downloads-heading {
  font-family: var(--font-display);
  font-size: 1.4rem;
  font-weight: 700;
  white-space: nowrap;
  color: var(--text);
}

.download-buttons {
  display: flex;
  gap: 0.5rem;
}

.btn-download {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  background: linear-gradient(135deg, #c9a227, #d4a843);
  color: #0f0f0f;
  text-decoration: none;
  padding: 0.6rem 1.25rem;
  border-radius: var(--radius);
  font-weight: 700;
  font-size: 0.875rem;
  position: relative;
  overflow: hidden;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  box-shadow: 0 4px 16px rgb(var(--accent-rgb) / 0.25);
}

.btn-download::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(105deg, transparent 40%, rgba(255, 255, 255, 0.3) 50%, transparent 60%);
  transform: translateX(-100%);
  transition: transform 0.5s ease;
}

.btn-download:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgb(var(--accent-rgb) / 0.35);
  opacity: 1;
  color: #0f0f0f;
}

.btn-download:hover::after {
  transform: translateX(100%);
}

.btn-icon {
  flex-shrink: 0;
}

.btn-platform {
  font-size: 0.875rem;
}

.downloads-fallback {
  color: var(--text-muted);
  font-size: 0.95rem;
}

.downloads-fallback a {
  color: var(--accent);
  font-weight: 600;
}

.release-notes-link {
  flex-basis: 100%;
  text-align: center;
  font-size: 0.85rem;
  opacity: 0.45;
}

.release-notes-link a {
  color: var(--text-muted);
  text-decoration: none;
}

.release-notes-link a:hover {
  opacity: 1;
  text-decoration: underline;
}

/* ── Features ───────────────────────────────────────────── */
.feature-cards {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
  width: 100%;
  max-width: 920px;
  margin-top: 1.25rem;
  position: relative;
  z-index: 1;
}

.feature-card {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius);
  padding: 0.6rem 0.75rem;
  transition: border-color 0.3s ease, box-shadow 0.3s ease, transform 0.3s ease;
  animation: fadeUp 0.6s ease-out both;
}

.feature-card:nth-child(1) { animation-delay: 0.4s; }
.feature-card:nth-child(2) { animation-delay: 0.5s; }
.feature-card:nth-child(3) { animation-delay: 0.6s; }
.feature-card:nth-child(4) { animation-delay: 0.7s; }

.feature-card:hover {
  border-color: var(--card-border-hover);
  box-shadow: 0 0 20px rgb(var(--accent-rgb) / 0.08);
  transform: translateY(-3px);
}

.feature-card h2 {
  font-size: 0.95rem;
  font-weight: 700;
  margin-bottom: 0.1rem;
  color: var(--text);
}

.feature-card p {
  font-size: 0.8rem;
  color: var(--text-muted);
  line-height: 1.3;
}

.feature-card a {
  color: var(--accent);
}

/* ── Lichess attribution medallion ─────────────────────── */
.attribution {
  display: flex;
  justify-content: center;
  padding: 0.5rem 1.5rem 1.25rem;
  animation: fadeUp 0.6s ease-out 0.8s both;
}

.medallion {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  background: rgb(var(--accent-rgb) / 0.1);
  border: 1.5px solid rgb(var(--accent-rgb) / 0.25);
  border-radius: 999px;
  padding: 0.55rem 1.25rem;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text);
}

.medallion a {
  color: var(--accent);
  text-underline-offset: 2px;
}

.medallion-logo path {
  fill: var(--text);
  stroke: var(--text);
}

/* ── Responsive ─────────────────────────────────────────── */
@media (max-width: 600px) {
  .hero-icon {
    width: 48px;
    height: 48px;
  }

  .hero-brand {
    gap: 0.75rem;
  }

  .hero-glow {
    width: 350px;
    height: 250px;
  }

  .hero-screenshot {
    transform: rotateX(0deg);
  }

  .downloads {
    flex-direction: column;
    gap: 0.5rem;
  }

  .download-buttons {
    flex-wrap: wrap;
    justify-content: center;
  }

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

@media (max-width: 380px) {
  .feature-cards {
    grid-template-columns: 1fr;
  }
}

/* ── Accessibility ──────────────────────────────────────── */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-delay: 0s !important;
    transition-duration: 0.01ms !important;
  }
}