/* 深度网盘 官网样式 —— 工业集团风：纯白底、深石墨字、1px 发丝线、直角、零阴影 */

:root{
  --bg:#ffffff;
  --bg-alt:#f6f7f8;
  --line:#e3e6e9;
  --line-2:#cfd5da;
  --text:#15191d;
  --text-2:#3c454d;
  --muted:#69737d;
  --faint:#9aa3ab;
  --accent:#1a5fd0;
  --accent-h:#154ba6;
  --accent-soft:#eaf1fd;
  --ink:#101418;

  --fs:-apple-system,BlinkMacSystemFont,"Segoe UI","Microsoft YaHei","PingFang SC","Hiragino Sans GB","Source Han Sans SC","Noto Sans CJK SC",sans-serif;
  --fm:"SFMono-Regular",Consolas,"Liberation Mono",Menlo,monospace;
  --serif:"Songti SC","Source Han Serif SC","Noto Serif CJK SC","SimSun",Georgia,"Times New Roman",serif;
  --wrap:1200px;
}

*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{
  margin:0;background:var(--bg);color:var(--text);
  font-family:var(--fs);font-size:15px;line-height:1.7;
  -webkit-font-smoothing:antialiased;
}
a{color:inherit;text-decoration:none}
h1,h2,h3,h4{margin:0;font-weight:600;line-height:1.25}
p{margin:0}
ul{margin:0;padding:0;list-style:none}
img{max-width:100%}
.wrap{width:100%;max-width:var(--wrap);margin:0 auto;padding:0 28px}

/* ------------------------------------------------------------------ topbar */
.topbar{
  position:sticky;top:0;z-index:40;background:rgba(255,255,255,.94);
  border-bottom:1px solid var(--line);backdrop-filter:saturate(180%) blur(6px);
}
.topbar-in{display:flex;align-items:center;gap:36px;height:64px}
.brand{display:flex;align-items:center;gap:10px;flex:none}
.brand-mark{
  width:32px;height:32px;flex:none;display:flex;align-items:center;justify-content:center;
  background:var(--ink);color:#fff;font-size:15px;font-weight:600;border-radius:3px;
}
.brand-txt{display:flex;flex-direction:column;line-height:1.15}
.brand-name{font-size:15px;font-weight:600;letter-spacing:.2px}
.brand-sub{font-family:var(--fm);font-size:9.5px;color:var(--faint);letter-spacing:1.4px}
.nav{display:flex;gap:28px;flex:1;min-width:0}
.nav a{font-size:14px;color:var(--muted);padding:4px 0;border-bottom:1px solid transparent}
.nav a:hover{color:var(--text);border-bottom-color:var(--line-2)}
.topbar-act{display:flex;align-items:center;gap:18px;flex:none}
.link{font-size:14px;color:var(--muted)}
.link:hover{color:var(--text)}

/* ------------------------------------------------------------------ button */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  height:38px;padding:0 18px;border:1px solid transparent;border-radius:3px;
  font-family:inherit;font-size:14px;font-weight:500;cursor:pointer;
  transition:background .15s ease,border-color .15s ease,color .15s ease;
}
.btn-primary{background:var(--accent);color:#fff;border-color:var(--accent)}
.btn-primary:hover{background:var(--accent-h);border-color:var(--accent-h)}
.btn-ghost{background:transparent;color:var(--text);border-color:var(--line-2)}
.btn-ghost:hover{border-color:var(--text)}
.btn-invert{background:#fff;color:var(--ink);border-color:#fff}
.btn-invert:hover{background:#e9ebee;border-color:#e9ebee}
.btn-lg{height:46px;padding:0 26px;font-size:15px}
.btn-block{width:100%}

/* --------------------------------------------------------------------- hero */
.hero{border-bottom:1px solid var(--line);background:var(--bg)}
.hero-grid{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:64px;align-items:center;padding:76px 28px 80px}
.eyebrow{
  font-family:var(--fm);font-size:11.5px;letter-spacing:1.2px;color:var(--muted);
  padding-left:12px;border-left:2px solid var(--accent);margin-bottom:22px;
}
.hero-title{
  font-family:var(--serif);font-size:74px;line-height:1.05;font-weight:600;
  letter-spacing:4px;margin-bottom:20px;
}
.hero-lede{font-size:16.5px;line-height:1.85;color:var(--text-2);max-width:33em;margin-bottom:30px}
.hero-act{display:flex;gap:12px;flex-wrap:wrap;margin-bottom:30px}
.hero-note{display:flex;flex-wrap:wrap;gap:10px 26px;font-size:13px;color:var(--muted)}
.hero-note li{padding-left:15px;position:relative}
.hero-note li::before{content:"";position:absolute;left:0;top:10px;width:5px;height:1px;background:var(--line-2)}

/* 产品实景：纯 CSS 线框 */
.hero-shot{border:1px solid var(--line-2);border-radius:4px;background:#fff;overflow:hidden}
.shot-bar{display:flex;align-items:center;gap:6px;padding:0 14px;height:38px;border-bottom:1px solid var(--line);background:var(--bg-alt)}
.shot-bar .dot{width:7px;height:7px;border-radius:50%;background:var(--line-2)}
.shot-path{margin-left:12px;font-family:var(--fm);font-size:11.5px;color:var(--muted)}
.shot-body{padding:6px 0 0}
.shot-row{display:grid;grid-template-columns:minmax(0,1fr) 92px 104px;gap:12px;padding:11px 18px;border-bottom:1px solid var(--line);font-size:13px;color:var(--text-2)}
.shot-row span:first-child{overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.shot-row span:not(:first-child){font-family:var(--fm);font-size:12px;color:var(--muted);text-align:right}
.shot-row.head{background:var(--bg-alt)}
.shot-row.head span{font-size:11px;letter-spacing:.6px;color:var(--faint);font-family:var(--fm)}
.shot-up{padding:16px 18px 20px}
.shot-up-label{font-size:12.5px;color:var(--text-2);margin-bottom:9px}
.shot-bar-track{height:5px;background:var(--panel-3,#eef0f2);border-radius:1px;overflow:hidden}
.shot-bar-track span{display:block;height:100%;background:var(--accent)}
.shot-up-num{margin-top:8px;font-family:var(--fm);font-size:11.5px;color:var(--muted)}

/* -------------------------------------------------------------------- specs */
.specs{background:var(--bg-alt);border-bottom:1px solid var(--line)}
.specs-row{display:grid;grid-template-columns:repeat(5,1fr)}
.spec{padding:26px 24px;border-right:1px solid var(--line);display:flex;flex-direction:column;gap:4px}
.spec:last-child{border-right:0}
.spec b{font-family:var(--fm);font-size:26px;font-weight:600;letter-spacing:-.5px;font-variant-numeric:tabular-nums}
.spec span{font-size:12.5px;color:var(--muted)}

/* ----------------------------------------------------------------- section */
.sect{padding:76px 0;border-bottom:1px solid var(--line)}
.sect-alt{background:var(--bg-alt)}
.sect-head{max-width:720px;margin-bottom:44px}
.sect-kicker{font-family:var(--fm);font-size:11.5px;letter-spacing:1.2px;color:var(--accent);margin-bottom:12px}
.sect-title{font-family:var(--serif);font-size:38px;letter-spacing:1px;margin-bottom:14px}
.sect-lede{font-size:15px;color:var(--muted);line-height:1.8}

/* ------------------------------------------------------------- capability */
.cap-list{border-top:1px solid var(--line)}
.cap{display:grid;grid-template-columns:72px minmax(0,1fr) 84px;gap:28px;align-items:start;padding:26px 0;border-bottom:1px solid var(--line)}
.cap-no{font-family:var(--fm);font-size:13px;color:var(--faint);font-variant-numeric:tabular-nums;padding-top:5px}
.cap-body h3{font-size:17px;margin-bottom:7px}
.cap-body p{font-size:14.5px;color:var(--muted);line-height:1.8;max-width:62em}
.cap-tag{
  justify-self:end;font-family:var(--fm);font-size:11px;color:var(--muted);
  border:1px solid var(--line-2);border-radius:2px;padding:3px 9px;margin-top:3px;
}

/* ------------------------------------------------------------------- plans */
.plans{display:grid;grid-template-columns:repeat(4,1fr);gap:0;border:1px solid var(--line);background:#fff}
.plan{padding:28px 24px 30px;border-right:1px solid var(--line);display:flex;flex-direction:column;position:relative}
.plan:last-child{border-right:0}
.plan.is-key{background:var(--accent-soft)}
.plan-flag{
  position:absolute;top:-1px;right:-1px;background:var(--accent);color:#fff;
  font-size:11px;padding:3px 10px;border-radius:0 3px 0 3px;
}
.plan-name{font-size:16px;margin-bottom:4px}
.plan-for{font-size:12.5px;color:var(--muted);margin-bottom:20px}
.plan-price{display:flex;align-items:baseline;gap:3px;margin-bottom:22px;min-height:52px}
.plan-price .cur{font-family:var(--fm);font-size:16px;color:var(--muted)}
.plan-price b{font-family:var(--fm);font-size:42px;font-weight:600;letter-spacing:-1.5px;font-variant-numeric:tabular-nums;line-height:1}
.plan-price b.ask{font-family:var(--fs);font-size:26px;letter-spacing:0}
.plan-price .per{font-size:13px;color:var(--muted);margin-left:4px}
.plan-spec{border-top:1px solid var(--line);margin-bottom:24px;flex:1}
.plan-spec li{display:flex;justify-content:space-between;gap:12px;padding:9px 0;border-bottom:1px solid var(--line);font-size:13px}
.plan-spec li span{color:var(--muted)}
.plan-spec li b{font-weight:500;font-family:var(--fm);font-size:12.5px;font-variant-numeric:tabular-nums}
.plan-foot{margin-top:22px;font-size:13px;color:var(--muted);line-height:1.8}

/* ----------------------------------------------------------------- support */
.sup-list{display:grid;grid-template-columns:repeat(4,1fr);border-top:1px solid var(--line)}
.sup{padding:24px 22px 26px;border-right:1px solid var(--line)}
.sup:last-child{border-right:0}
.sup-no{font-family:var(--fm);font-size:12px;color:var(--faint);display:block;margin-bottom:10px}
.sup h3{font-size:16px;margin-bottom:8px}
.sup p{font-size:13.5px;color:var(--muted);line-height:1.8}

/* --------------------------------------------------------------------- faq */
.faq{border-top:1px solid var(--line)}
.faq-i{border-bottom:1px solid var(--line)}
.faq-i summary{
  list-style:none;cursor:pointer;padding:18px 30px 18px 0;position:relative;
  font-size:15.5px;font-weight:500;
}
.faq-i summary::-webkit-details-marker{display:none}
.faq-i summary::after{
  content:"";position:absolute;right:4px;top:26px;width:9px;height:9px;
  border-right:1px solid var(--muted);border-bottom:1px solid var(--muted);
  transform:rotate(45deg);transition:transform .18s ease;
}
.faq-i[open] summary::after{transform:rotate(-135deg);top:30px}
.faq-i p{padding:0 40px 20px 0;font-size:14.5px;color:var(--muted);line-height:1.85}

/* --------------------------------------------------------------------- cta */
.cta{background:var(--ink);color:#fff;padding:52px 0}
.cta-in{display:flex;align-items:center;justify-content:space-between;gap:32px;flex-wrap:wrap}
.cta-title{font-family:var(--serif);font-size:30px;letter-spacing:1px;margin-bottom:8px}
.cta-sub{font-size:14px;color:#aeb6bd}

/* ------------------------------------------------------------------ footer */
.foot{background:var(--bg);padding:46px 0 26px}
.foot-top{display:flex;justify-content:space-between;gap:40px;flex-wrap:wrap;padding-bottom:34px;border-bottom:1px solid var(--line)}
.foot-brand{display:flex;align-items:center;gap:12px}
.foot-name{font-size:15px;font-weight:600}
.foot-sub{font-family:var(--fm);font-size:10px;color:var(--faint);letter-spacing:1px}
.foot-nav{display:flex;gap:64px}
.foot-nav h4{font-size:12.5px;margin-bottom:12px;color:var(--faint);font-weight:500;letter-spacing:.5px}
.foot-nav a{display:block;font-size:13.5px;color:var(--muted);padding:4px 0}
.foot-nav a:hover{color:var(--text)}
.foot-bottom{display:flex;justify-content:space-between;gap:20px;flex-wrap:wrap;padding-top:22px;font-size:12.5px;color:var(--muted)}
.foot-ops{font-family:var(--fm);font-size:11.5px;color:var(--faint)}

/* -------------------------------------------------------------- responsive */
@media (max-width:1040px){
  .hero-grid{grid-template-columns:1fr;gap:44px;padding:56px 28px 60px}
  .hero-title{font-size:58px}
  .plans{grid-template-columns:repeat(2,1fr)}
  .plan:nth-child(2n){border-right:0}
  .plan:nth-child(-n+2){border-bottom:1px solid var(--line)}
  .specs-row{grid-template-columns:repeat(3,1fr)}
  .spec:nth-child(3n){border-right:0}
  .spec:nth-child(-n+3){border-bottom:1px solid var(--line)}
  .sup-list{grid-template-columns:repeat(2,1fr)}
  .sup:nth-child(2n){border-right:0}
  .sup:nth-child(-n+2){border-bottom:1px solid var(--line)}
}
@media (max-width:720px){
  .wrap{padding:0 18px}
  .nav{display:none}
  .topbar-in{gap:16px;height:58px}
  .hero-grid{padding:44px 18px 48px}
  .hero-title{font-size:44px;letter-spacing:2px}
  .sect{padding:52px 0}
  .sect-title{font-size:28px}
  .specs-row{grid-template-columns:repeat(2,1fr)}
  .spec{border-bottom:1px solid var(--line)}
  .spec:nth-child(2n){border-right:0}
  .plans{grid-template-columns:1fr}
  .plan{border-right:0;border-bottom:1px solid var(--line)}
  .sup-list{grid-template-columns:1fr}
  .sup{border-right:0;border-bottom:1px solid var(--line)}
  .cap{grid-template-columns:44px minmax(0,1fr);gap:14px}
  .cap-tag{display:none}
  .foot-nav{gap:36px}
}