/* Giao diện trang chi tiết từng mốc (su-kien/*.html) */
:root {
  --c: #b7862e;
  --bg: #110c0a;
  --ink: #f3e9d8;
  --muted: #b9a992;
  --gold: #e8c46a;
  --line: rgba(255, 240, 215, .1);
  --card: rgba(24, 17, 14, .62);
  color-scheme: dark;
}

* { box-sizing: border-box; }
html, body { margin: 0; }
body {
  font-family: 'Be Vietnam Pro', system-ui, -apple-system, 'Segoe UI', sans-serif;
  color: var(--ink);
  background:
    radial-gradient(1100px 700px at 10% 0%, color-mix(in oklab, var(--c) 34%, transparent), transparent 70%),
    var(--bg);
  min-height: 100vh;
  overflow-x: hidden;
  line-height: 1.6;
}
a { color: inherit; }

.bg {
  position: fixed; inset: -80px; z-index: -1;
  background-size: cover; background-position: center;
  filter: blur(60px) saturate(1.3);
  opacity: .18;
  pointer-events: none;
}

/* ---------- Thanh trên ---------- */
.bar {
  position: sticky; top: 0; z-index: 10;
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
  padding: 14px max(16px, calc((100% - 1180px) / 2));
  background: rgba(17, 12, 10, .72);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
}
.brand {
  font-family: 'Playfair Display', Georgia, serif;
  font-size: 22px; font-weight: 700; text-decoration: none;
  background: linear-gradient(90deg, var(--gold), #fff3d6);
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.back {
  font-size: 14px; text-decoration: none; color: var(--muted);
  padding: 7px 14px; border-radius: 999px; border: 1px solid var(--line);
  transition: color .2s, border-color .2s, background .2s;
}
.back:hover { color: var(--ink); border-color: var(--gold); background: rgba(255, 255, 255, .05); }

.wrap { max-width: 1180px; margin: 0 auto; padding: 28px 16px 40px; }

/* ---------- Hero ---------- */
.hero {
  display: grid;
  grid-template-columns: 1.05fr 1fr;
  gap: 40px;
  align-items: center;
  margin-bottom: 44px;
}
.hero-pic {
  position: relative; margin: 0;
  aspect-ratio: 4 / 3;
  border-radius: 24px; overflow: hidden;
  border: 1px solid var(--line);
  background: radial-gradient(120% 90% at 20% 10%, color-mix(in oklab, var(--c) 40%, transparent), transparent 70%), rgba(20, 14, 12, .6);
  box-shadow: 0 30px 80px rgba(0, 0, 0, .45);
  animation: rise .8s cubic-bezier(.2, .8, .2, 1) both;
}
.hero-pic img {
  width: 100%; height: 100%; object-fit: cover; display: block;
  animation: kenburns 22s ease-in-out infinite alternate;
}
.hero-pic.contain img { object-fit: contain; padding: 12px; animation: none; background: rgba(255, 255, 255, .03); }
.hero-pic figcaption { position: absolute; left: 12px; right: 12px; bottom: 12px; display: flex; justify-content: flex-end; }
.hero-pic figcaption a {
  max-width: 100%; font-size: 11px; text-decoration: none; color: #d8c9b2;
  padding: 4px 10px; border-radius: 999px; background: rgba(0, 0, 0, .6);
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
.hero-pic figcaption a:hover { text-decoration: underline; }

.hero-text { animation: rise .8s .1s cubic-bezier(.2, .8, .2, 1) both; }
.era {
  display: inline-block; font-size: 12.5px; letter-spacing: 2.5px; text-transform: uppercase; text-decoration: none;
  color: color-mix(in oklab, var(--c) 55%, #fff);
  padding: 5px 12px; border-radius: 999px;
  border: 1px solid color-mix(in oklab, var(--c) 60%, transparent);
  background: color-mix(in oklab, var(--c) 15%, transparent);
}
.era:hover { background: color-mix(in oklab, var(--c) 30%, transparent); }
.year {
  font-family: 'Playfair Display', Georgia, serif; font-weight: 800;
  font-size: clamp(56px, 8vw, 104px); line-height: 1; margin: 14px 0 2px;
  background: linear-gradient(180deg, #fff6e0 20%, color-mix(in oklab, var(--c) 70%, var(--gold)));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.year .suf { font-size: .32em; margin-left: .2em; letter-spacing: 1px; }
.date { color: var(--muted); font-size: 15px; }
h1 {
  font-family: 'Playfair Display', Georgia, serif;
  font-size: clamp(28px, 3.4vw, 44px); line-height: 1.15; margin: 14px 0 14px;
}
.lede { font-size: 18px; color: #eadfcd; margin: 0; }

/* ---------- Bài viết ---------- */
.grid { display: grid; grid-template-columns: minmax(0, 1fr) 320px; gap: 40px; align-items: start; }
.article section { margin-bottom: 30px; }
.article h2 {
  font-family: 'Playfair Display', Georgia, serif; font-size: 26px; margin: 0 0 12px;
  display: flex; align-items: center; gap: 12px;
}
.article h2::before { content: ''; width: 22px; height: 3px; border-radius: 2px; background: var(--c); flex: none; }
.article p { font-size: 17.5px; line-height: 1.8; color: #eadfcd; margin: 0 0 14px; }

.trivia {
  margin-top: 8px; padding: 20px 24px; border-radius: 18px;
  background: color-mix(in oklab, var(--c) 12%, rgba(24, 17, 14, .6));
  border: 1px solid color-mix(in oklab, var(--c) 35%, transparent);
}
.trivia h3 { margin: 0 0 8px; font-size: 16px; color: color-mix(in oklab, var(--c) 45%, #fff); }
.trivia ul { margin: 0; padding-left: 20px; }
.trivia li { margin: 6px 0; color: #eadfcd; }

.side { position: sticky; top: 84px; display: grid; gap: 18px; }
.card {
  background: var(--card); border: 1px solid var(--line); border-radius: 18px; padding: 18px 20px;
  backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px);
}
.card h3 { margin: 0 0 10px; font-size: 13px; letter-spacing: 2px; text-transform: uppercase; color: var(--gold); }
.facts { margin: 0; display: grid; gap: 10px; }
.facts dt { font-size: 12.5px; color: var(--muted); }
.facts dd { margin: 1px 0 0; font-size: 15px; font-weight: 500; }
.refs { margin: 0; padding-left: 18px; font-size: 14px; }
.refs li { margin: 6px 0; }
.refs a { color: #f0d9a8; }

/* ---------- Video ---------- */
.videos { margin: 16px 0 40px; }
.videos h2 { font-family: 'Playfair Display', Georgia, serif; font-size: 26px; margin: 0 0 16px; }
.vgrid { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 20px; }
.yt { border-radius: 18px; overflow: hidden; background: var(--card); border: 1px solid var(--line); }
.yt-play, .yt iframe {
  position: relative; display: block; width: 100%; aspect-ratio: 16 / 9; border: 0; padding: 0;
  background: #000; cursor: pointer;
}
.yt-play img { width: 100%; height: 100%; object-fit: cover; display: block; transition: transform .5s, opacity .3s; opacity: .9; }
.yt-play:hover img { transform: scale(1.04); opacity: 1; }
.play {
  position: absolute; left: 50%; top: 50%; width: 68px; height: 48px; transform: translate(-50%, -50%);
  border-radius: 14px; background: rgba(230, 33, 23, .92); box-shadow: 0 8px 30px rgba(0, 0, 0, .5);
  transition: transform .2s;
}
.play::after {
  content: ''; position: absolute; left: 27px; top: 14px;
  border-style: solid; border-width: 10px 0 10px 17px; border-color: transparent transparent transparent #fff;
}
.yt-play:hover .play { transform: translate(-50%, -50%) scale(1.08); }
.yt-meta { padding: 12px 16px 16px; display: grid; gap: 3px; }
.yt-meta b { font-size: 15px; line-height: 1.4; }
.yt-meta span { font-size: 13px; color: var(--muted); }
.yt-meta a { font-size: 13px; color: #f0d9a8; text-decoration: none; margin-top: 4px; }
.yt-meta a:hover { text-decoration: underline; }

/* ---------- Mốc trước / sau ---------- */
.pn { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; margin-top: 12px; }
.pn a {
  display: grid; gap: 2px; padding: 16px 20px; border-radius: 16px; text-decoration: none;
  background: var(--card); border: 1px solid var(--line);
  border-left: 3px solid var(--ec);
  transition: transform .2s, border-color .2s, background .2s;
}
.pn a.next { text-align: right; border-left: 1px solid var(--line); border-right: 3px solid var(--ec); }
.pn a:hover { transform: translateY(-2px); background: color-mix(in oklab, var(--ec) 14%, var(--card)); }
.pn small { color: var(--muted); font-size: 13px; }
.pn span { font-weight: 600; }

.foot {
  max-width: 1180px; margin: 0 auto; padding: 24px 16px 40px;
  font-size: 12.5px; color: var(--muted); border-top: 1px solid var(--line);
}

@keyframes rise { from { opacity: 0; transform: translateY(18px); } to { opacity: 1; transform: none; } }
@keyframes kenburns { from { transform: scale(1); } to { transform: scale(1.08) translate(-1.5%, -1%); } }

@media (max-width: 900px) {
  .hero { grid-template-columns: 1fr; gap: 22px; margin-bottom: 30px; }
  .grid { grid-template-columns: 1fr; gap: 10px; }
  .side { position: static; }
  .article p { font-size: 16.5px; }
  .back { font-size: 13px; padding: 6px 12px; }
}
@media (max-width: 560px) {
  .pn { grid-template-columns: 1fr; }
  .vgrid { grid-template-columns: 1fr; }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation: none !important; transition: none !important; }
}