:root {
  --bg: #f4f8fc;
  --bg-soft: #ffffff;
  --ink: #1f2d3d;
  --ink-soft: #5b6b7b;
  --brand: #2f80ed;
  --brand-deep: #1b5fc4;
  --accent: #ff8a3d;
  --line: #e3ecf5;
  --shadow: 0 10px 30px rgba(31, 45, 61, 0.08);
  --radius: 16px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", system-ui, -apple-system, sans-serif;
  background: var(--bg);
  color: var(--ink);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

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

.wrap { max-width: 960px; margin: 0 auto; padding: 0 20px; }

/* ---------- 顶栏 ---------- */
.topbar {
  position: sticky; top: 0; z-index: 20;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: saturate(160%) blur(10px);
  border-bottom: 1px solid var(--line);
}
.topbar .wrap {
  display: flex; align-items: center; justify-content: space-between;
  height: 64px;
}
.logo { display: flex; align-items: center; gap: 10px; font-weight: 800; font-size: 18px; }
.logo .dot {
  width: 12px; height: 12px; border-radius: 50%;
  background: var(--brand); box-shadow: 0 0 0 4px rgba(47, 128, 237, 0.18);
}
.logo small { display: block; font-size: 12px; font-weight: 500; color: var(--ink-soft); }
.nav { display: flex; gap: 22px; font-size: 15px; }
.nav a { color: var(--ink-soft); transition: color .2s; }
.nav a:hover { color: var(--brand); }

/* ---------- 英雄区 ---------- */
.hero { padding: 40px 0 8px; }
.badge {
  display: inline-flex; align-items: center; gap: 6px;
  background: rgba(47, 128, 237, 0.1); color: var(--brand-deep);
  padding: 6px 14px; border-radius: 999px; font-size: 13px; font-weight: 600;
}
.hero h1 {
  font-size: 34px; line-height: 1.25; margin: 16px 0 10px;
  letter-spacing: .5px;
}
.hero p.lead { color: var(--ink-soft); font-size: 16px; max-width: 640px; }

/* ---------- 播放器 ---------- */
.player-card {
  background: var(--bg-soft); border: 1px solid var(--line);
  border-radius: var(--radius); box-shadow: var(--shadow);
  overflow: hidden; margin: 26px 0;
}
.player-card video {
  width: 100%; display: block; background: #000; aspect-ratio: 16 / 9;
}
.player-meta { padding: 18px 20px; }
.player-meta h2 { font-size: 20px; margin-bottom: 6px; }
.player-meta .sub { color: var(--ink-soft); font-size: 14px; }
.player-meta .tags { margin-top: 12px; display: flex; flex-wrap: wrap; gap: 8px; }
.tag {
  font-size: 12px; color: var(--brand-deep);
  background: rgba(47, 128, 237, 0.08); padding: 4px 10px; border-radius: 8px;
}

/* ---------- 区块标题 ---------- */
.section { padding: 30px 0; }
.section h3 { font-size: 22px; margin-bottom: 4px; }
.section .hint { color: var(--ink-soft); font-size: 14px; margin-bottom: 18px; }

/* ---------- 视频列表 ---------- */
.grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 18px; }
.card {
  background: var(--bg-soft); border: 1px solid var(--line);
  border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow);
  transition: transform .2s, box-shadow .2s;
}
.card:hover { transform: translateY(-4px); box-shadow: 0 16px 40px rgba(31,45,61,.12); }
.card .thumb {
  aspect-ratio: 16/9; background: linear-gradient(135deg, #2f80ed, #56ccf2);
  display: flex; align-items: center; justify-content: center; color: #fff;
  font-size: 28px; font-weight: 800;
}
.card .body { padding: 14px 16px; }
.card .body .date { font-size: 12px; color: var(--ink-soft); }
.card .body h4 { font-size: 16px; margin: 4px 0 6px; }
.card .body p { font-size: 13px; color: var(--ink-soft); }

/* ---------- 关于 ---------- */
.about {
  background: var(--bg-soft); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 24px; box-shadow: var(--shadow);
}
.about p { color: var(--ink-soft); margin-top: 8px; }

/* ---------- 页脚 ---------- */
.footer {
  border-top: 1px solid var(--line); margin-top: 30px;
  padding: 24px 0; color: var(--ink-soft); font-size: 13px; text-align: center;
}

/* ---------- 密码门 ---------- */
#gate {
  position: fixed; inset: 0; z-index: 999;
  display: flex; align-items: center; justify-content: center;
  background: linear-gradient(135deg, #1b5fc4, #2f80ed);
}
#gate .box {
  background: #fff; border-radius: 20px; padding: 34px 30px;
  width: min(360px, 88vw); box-shadow: 0 20px 60px rgba(0,0,0,.25);
  text-align: center;
}
#gate .box .lock { font-size: 40px; }
#gate .box h2 { font-size: 20px; margin: 10px 0 4px; }
#gate .box p { color: var(--ink-soft); font-size: 13px; margin-bottom: 18px; }
#gate input {
  width: 100%; padding: 12px 14px; border: 1px solid var(--line);
  border-radius: 10px; font-size: 15px; outline: none; margin-bottom: 12px;
}
#gate input:focus { border-color: var(--brand); }
#gate button {
  width: 100%; padding: 12px; border: 0; border-radius: 10px;
  background: var(--brand); color: #fff; font-size: 15px; font-weight: 700;
  cursor: pointer; transition: background .2s;
}
#gate button:hover { background: var(--brand-deep); }
#gate .err { color: #e74c3c; font-size: 13px; min-height: 18px; margin-top: 8px; }

/* ---------- 响应式 ---------- */
@media (max-width: 600px) {
  .nav { gap: 14px; font-size: 14px; }
  .hero h1 { font-size: 26px; }
  .topbar .wrap { height: 56px; }
}

/* ---------- 评论入口按钮 ---------- */
.cmt-bar {
  display: flex; align-items: center; gap: 10px;
  margin: 14px 0 4px;
}
.cmt-btn {
  display: inline-flex; align-items: center; gap: 6px;
  background: var(--brand); color: #fff; font-weight: 600;
  padding: 9px 16px; border-radius: 10px; font-size: 14px;
  transition: background .2s;
}
.cmt-btn:hover { background: var(--brand-deep); }
.cmt-count { color: var(--ink-soft); font-size: 13px; }

/* ---------- 留言板 ---------- */
.gb-head { margin-bottom: 12px; }
.gb-form { display: flex; flex-direction: column; gap: 10px; margin-bottom: 18px; }
.gb-form textarea {
  width: 100%; border: 1px solid var(--line); border-radius: 10px;
  padding: 12px; font: inherit; resize: vertical; outline: none;
}
.gb-form textarea:focus { border-color: var(--brand); }
.gb-form button {
  align-self: flex-end; background: var(--brand); color: #fff;
  border: 0; border-radius: 10px; padding: 10px 22px; font-weight: 600; cursor: pointer;
}
.gb-form button:hover { background: var(--brand-deep); }
.gb-list { display: flex; flex-direction: column; gap: 12px; }
.gb-item { background: var(--bg); border: 1px solid var(--line); border-radius: 12px; padding: 12px 14px; }
.gb-meta { display: flex; justify-content: space-between; font-size: 13px; color: var(--ink-soft); margin-bottom: 4px; }
.gb-meta b { color: var(--ink); }
.gb-text { font-size: 15px; white-space: pre-wrap; word-break: break-word; }
.gb-empty { color: var(--ink-soft); font-size: 14px; }

/* ---------- 数据看板 ---------- */
.stat-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: 14px; margin: 18px 0; }
.stat {
  background: var(--bg-soft); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 18px; text-align: center; box-shadow: var(--shadow);
}
.stat .num { font-size: 30px; font-weight: 800; color: var(--brand-deep); }
.stat .lbl { font-size: 13px; color: var(--ink-soft); margin-top: 4px; }
table.vt { width: 100%; border-collapse: collapse; background: var(--bg-soft); border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; }
table.vt th, table.vt td { padding: 11px 14px; text-align: left; font-size: 14px; border-bottom: 1px solid var(--line); }
table.vt th { background: #eef4fb; color: var(--ink-soft); font-weight: 600; }
table.vt tr:last-child td { border-bottom: 0; }
.link-btn { color: var(--brand); cursor: pointer; font-weight: 600; background: none; border: 0; font: inherit; }
.detail { margin-top: 18px; }
.detail h4 { font-size: 16px; margin-bottom: 10px; }