/* ============================================================
   5TV 音乐官网 — 与 App / 后台同一套暗色体系
   #0A0A0B 底/ #141417 卡/ #1DB954 唯一信号色
   ============================================================ */
:root {
  --bg: #0A0A0B;
  --card: #141417;
  --line: rgba(255,255,255,0.08);
  --txt: #FAFAFA;
  --txt2: #A1A1AA;
  --txt3: #71717A;
  --green: #1DB954;
  --ok: #34D399;
  --warn: #FBBF24;
  --radius: 12px;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  background: var(--bg); color: var(--txt);
  font-family: "PingFang SC", "Noto Sans SC", "Microsoft YaHei", -apple-system, sans-serif;
  font-size: 15px; line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
.wrap { max-width: 1200px; margin: 0 auto; padding: 0 40px; }

/* ---------- 导航 ---------- */
.nav {
  position: sticky; top: 0; z-index: 50;
  background: rgba(10,10,11,0.8);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--line);
}
.nav-in { display: flex; align-items: center; justify-content: space-between; height: 72px; }
.brand { display: flex; align-items: center; gap: 10px; }
.brand b { font-size: 16px; font-weight: 700; }
.menu { display: flex; gap: 30px; }
.menu a { font-size: 14px; color: var(--txt2); transition: color .18s; }
.menu a:hover { color: var(--txt); }
.menu a.on { color: var(--green); font-weight: 500; }
.nav-r { display: flex; align-items: center; gap: 12px; }
.pill {
  display: inline-flex; align-items: center; gap: 7px;
  height: 36px; padding: 0 14px; border-radius: 18px;
  background: rgba(255,255,255,0.06); font-size: 12px; color: var(--txt2);
}
.pill .dot { width: 7px; height: 7px; border-radius: 50%; background: var(--ok); }
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  height: 36px; padding: 0 18px; border-radius: 18px;
  border: none; background: rgba(255,255,255,0.07); color: var(--txt);
  font-size: 13px; font-family: inherit; cursor: pointer;
  transition: transform .15s, background .15s;
}
.btn:hover { transform: translateY(-1px); }
.btn.primary { background: var(--green); color: #0A0A0B; font-weight: 600; }
.btn.lg { height: 48px; padding: 0 26px; border-radius: 24px; font-size: 15px; }

/* ---------- Hero ---------- */
.hero {
  position: relative; overflow: hidden;
  padding: 90px 0 100px;
  background:
    radial-gradient(900px 480px at 12% -10%, rgba(29,185,84,0.13), transparent 60%),
    radial-gradient(700px 420px at 88% 10%, rgba(124,58,237,0.10), transparent 60%);
}
.hero-in { display: grid; grid-template-columns: 1fr 420px; gap: 70px; align-items: center; }
.badge {
  display: inline-block; padding: 5px 12px; border-radius: 14px;
  background: rgba(29,185,84,0.14); color: var(--green);
  font-size: 12px; font-weight: 500; margin-bottom: 20px;
}
.hero h1 { font-size: 52px; line-height: 1.18; font-weight: 800; letter-spacing: -0.5px; }
.lead { font-size: 16px; color: var(--txt2); margin: 22px 0 32px; max-width: 500px; line-height: 1.75; }
.cta { display: flex; gap: 14px; }
.feats {
  list-style: none; display: grid; grid-template-columns: repeat(4, 1fr);
  gap: 20px; margin-top: 52px; padding-top: 32px;
  border-top: 1px solid var(--line);
}
.feats b { display: block; font-size: 26px; font-weight: 700; }
.feats span { font-size: 12px; color: var(--txt3); }

/* 手机模型 */
.hero-vis { display: flex; justify-content: center; }
.phone {
  width: 300px; border-radius: 34px; padding: 9px;
  background: linear-gradient(160deg, #2A2A30, #131316);
  box-shadow: 0 40px 80px rgba(0,0,0,0.6), 0 0 0 1px rgba(255,255,255,0.06);
  transform: rotate(-2deg);
}
.pb {
  border-radius: 26px; background: #121212; overflow: hidden;
  display: flex; flex-direction: column;
}
.pb-status {
  height: 44px; display: flex; align-items: center; justify-content: space-between;
  padding: 0 18px; font-size: 12px; font-weight: 600;
}
.pb-ic { display: flex; gap: 5px; align-items: center; }
.pb-stage {
  position: relative; aspect-ratio: 16/10;
  background: linear-gradient(135deg, #23785A, #0F141F);
  display: flex; align-items: center; justify-content: center;
}
.pb-badge {
  position: absolute; top: 12px; left: 12px;
  background: rgba(0,0,0,0.55); padding: 3px 9px; border-radius: 10px; font-size: 10px;
}
.pb-play {
  width: 52px; height: 52px; border-radius: 50%;
  background: rgba(0,0,0,0.45); border: 1px solid rgba(255,255,255,0.28);
  display: flex; align-items: center; justify-content: center;
}
.pb-ctl { padding: 14px 16px 18px; }
.pb-ctl b { display: block; font-size: 17px; font-weight: 700; }
.pb-ctl > span { font-size: 11px; color: var(--txt2); }
.pb-track { height: 3px; background: rgba(255,255,255,0.18); border-radius: 2px; margin: 12px 0; }
.pb-track i { display: block; width: 34%; height: 100%; background: var(--green); border-radius: 2px; }
.pb-btns { display: flex; align-items: center; justify-content: space-between; }
.pb-main {
  width: 48px; height: 48px; border-radius: 50%; background: var(--green);
  display: flex; align-items: center; justify-content: center;
}

/* ---------- 区块 ---------- */
.sec { padding: 96px 0; }
.sec.alt { background: rgba(255,255,255,0.015); }
.sec-head { max-width: 640px; margin-bottom: 46px; }
.eyebrow {
  display: inline-block; font-size: 12px; font-weight: 600;
  letter-spacing: 0.12em; color: var(--green); text-transform: uppercase;
  margin-bottom: 12px;
}
.sec-head h2 { font-size: 34px; font-weight: 700; letter-spacing: -0.3px; }
.sec-sub { font-size: 15px; color: var(--txt2); margin-top: 12px; }

/* 安装步骤 */
.inst-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.inst {
  background: rgba(255,255,255,0.04); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 26px;
}
.inst .num {
  display: flex; align-items: center; justify-content: center;
  width: 32px; height: 32px; border-radius: 50%;
  background: var(--green); color: #0A0A0B; font-weight: 700; font-size: 15px;
  margin-bottom: 16px;
}
.inst h3 { font-size: 16px; font-weight: 600; margin-bottom: 8px; }
.inst p { font-size: 13px; color: var(--txt2); line-height: 1.7; }

.inst-cta {
  display: flex; align-items: center; gap: 40px;
  margin: 44px 0 40px; padding: 32px;
  background: rgba(255,255,255,0.03); border: 1px solid var(--line); border-radius: var(--radius);
}
.qr { display: flex; flex-direction: column; align-items: center; gap: 8px; }
.qr-tx { font-size: 12px; color: var(--txt2); }
.qr-code { padding: 8px; background: #fff; border-radius: 8px; }
.qr-tip { font-size: 11px; color: var(--txt3); }

/* 环境自检：让用户一眼看到「为什么装不上」，而不是反复尝试 */
.env-warn {
  display: flex; align-items: flex-start; gap: 10px;
  padding: 14px 16px; margin-bottom: 18px;
  background: rgba(251,191,36,0.10); border: 1px solid rgba(251,191,36,0.28);
  border-radius: 10px; color: #FBBF24;
  font-size: 12px; line-height: 19px;
}
.env-warn svg { flex-shrink: 0; margin-top: 1px; }
.env-warn b { color: #FBBF24; }
.env-warn code {
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: 11px; padding: 1px 5px; border-radius: 4px;
  background: rgba(0,0,0,0.3);
}
.env-check {
  padding: 20px 22px;
  background: rgba(255,255,255,0.02); border: 1px solid var(--line); border-radius: var(--radius);
}
.env-check h4 {
  font-size: 13px; font-weight: 600; color: var(--txt);
  margin-bottom: 14px; letter-spacing: 0.2px;
}
.env-check ul { list-style: none; display: flex; flex-direction: column; gap: 11px; }
.env-check li {
  display: flex; align-items: center; gap: 10px;
  font-size: 12px;
}
.env-check li b { color: var(--txt); font-weight: 500; min-width: 66px; }
.env-check li .d { color: var(--txt2); }
.env-check .dot {
  width: 7px; height: 7px; border-radius: 4px; flex-shrink: 0;
  background: #34D399;
}
.env-check li.warn .dot { background: #FBBF24; }
.env-check li.warn .d { color: #FBBF24; }

.tips { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.tip { border-left: 2px solid var(--green); padding-left: 16px; }
.tip b { font-size: 13px; display: block; margin-bottom: 6px; }
.tip p { font-size: 12px; color: var(--txt3); line-height: 1.75; }

/* 曲库 */
.lib-stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; margin-bottom: 28px; }
.ls {
  background: rgba(255,255,255,0.04); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 22px; text-align: center;
}
.ls b { display: block; font-size: 30px; font-weight: 700; }
.ls span { font-size: 12px; color: var(--txt3); }
.lib-list { display: grid; grid-template-columns: 1fr 1fr; gap: 10px 24px; }
.li {
  display: flex; align-items: center; gap: 14px;
  padding: 10px 12px; border-radius: 10px; transition: background .16s;
}
.li:hover { background: rgba(255,255,255,0.04); }
.li-c {
  width: 44px; height: 44px; border-radius: 8px; flex-shrink: 0;
  display: flex; align-items: center; justify-content: center;
}
.li-t { flex: 1; min-width: 0; }
.li-t b { display: block; font-size: 14px; font-weight: 600; }
.li-t i { font-style: normal; font-size: 11px; color: var(--txt3); }
.li-e { font-size: 11px; color: var(--txt3); font-family: "JetBrains Mono", monospace; }
.lib-more { margin-top: 24px; font-size: 14px; }
.lib-more a { color: var(--green); }
.lib-err { color: var(--txt3); font-size: 13px; }

/* 关于 */
.about-in { display: grid; grid-template-columns: 1fr 400px; gap: 60px; align-items: start; }
.checks { list-style: none; margin-top: 22px; }
.checks li {
  position: relative; padding-left: 26px; margin-bottom: 12px;
  font-size: 14px; color: var(--txt2);
}
.checks li::before {
  content: ""; position: absolute; left: 0; top: 8px;
  width: 8px; height: 8px; border-radius: 50%;
  background: var(--green);
}
.about-card {
  background: rgba(255,255,255,0.04); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 26px;
}
.about-card h4 { font-size: 14px; margin-bottom: 18px; }
.about-card dl { display: grid; grid-template-columns: 72px 1fr; gap: 12px 16px; }
.about-card dt { font-size: 12px; color: var(--txt3); }
.about-card dd { font-size: 13px; }

/* 页脚 */
.foot { border-top: 1px solid var(--line); padding: 30px 0; }
.foot-in { display: flex; align-items: center; justify-content: space-between; font-size: 12px; color: var(--txt3); }
.foot-in a { color: var(--txt2); }
.foot-x { color: var(--txt3); }

/* ---------- 响应式 ---------- */
@media (max-width: 980px) {
  .wrap { padding: 0 22px; }
  .hero-in { grid-template-columns: 1fr; gap: 50px; }
  .hero h1 { font-size: 38px; }
  .hero-vis { order: -1; }
  .menu { display: none; }
  .inst-grid, .tips { grid-template-columns: 1fr; }
  .lib-list { grid-template-columns: 1fr; }
  .lib-stats { grid-template-columns: 1fr 1fr; }
  .about-in { grid-template-columns: 1fr; gap: 34px; }
  .inst-cta { flex-direction: column; text-align: center; }
  .sec { padding: 66px 0; }
  .foot-in { flex-direction: column; gap: 8px; text-align: center; }
}
@media (max-width: 560px) {
  .hero h1 { font-size: 30px; }
  .feats { grid-template-columns: 1fr 1fr; gap: 16px; }
  .cta { flex-direction: column; }
  .btn.lg { width: 100%; }
  .phone { transform: none; width: 270px; }
}