@charset "utf-8";
/* ============================================================
   YT视频下载器 · 产品页样式
   ------------------------------------------------------------
   顺序：变量/基础 → nav → buttons → hero → app screenshot（软件界面截图）
        → section → features → steps+formats → video tutorial
        → download cta → 网盘下载 → footer → toast → reveal → 响应式
   颜色统一走 :root 变量，改主题只动最上面那一组。
   断点：1080 / 900 / 600
   ============================================================ */

:root{
  --bg:#0a0708;
  --surface:rgba(255,186,186,.038);
  --surface-2:rgba(255,186,186,.07);
  --border:rgba(255,196,196,.085);
  --border-2:rgba(255,196,196,.16);
  --text:#f7f1f2;
  --dim:#a89a9e;
  --mute:#7d6e72;
  --accent:#ef4444;
  --accent-lt:#ff8b8b;
  --maxw:1180px;
  --sans:"Inter","SF Pro Text",-apple-system,BlinkMacSystemFont,"Segoe UI Variable Text","Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,sans-serif;
  --mono:ui-monospace,"SF Mono","JetBrains Mono","Cascadia Mono",Menlo,Consolas,monospace;
}
*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{
  margin:0;background:var(--bg);color:var(--text);
  font-family:var(--sans);font-size:16px;line-height:1.65;
  overflow-x:hidden;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;
}
h1,h2,h3,h4,p,figure{margin:0}
a{color:inherit;text-decoration:none}
button{font:inherit;color:inherit;background:none;border:0;cursor:pointer}
svg{display:block}
::selection{background:rgba(239,68,68,.34)}
::-webkit-scrollbar{width:10px;height:10px}
::-webkit-scrollbar-track{background:#0a0708}
::-webkit-scrollbar-thumb{background:#2c2126;border-radius:6px;border:2px solid #0a0708}
::-webkit-scrollbar-thumb:hover{background:#3e2f34}
.wrap{width:100%;max-width:var(--maxw);margin:0 auto;padding:0 32px}

/* ---------- nav ---------- */
.nav{position:sticky;top:0;z-index:60;background:rgba(10,7,8,.45);backdrop-filter:blur(16px) saturate(160%);-webkit-backdrop-filter:blur(16px) saturate(160%);border-bottom:1px solid transparent;transition:background .3s ease,border-color .3s ease}
.nav.stuck{background:rgba(10,7,8,.86);border-bottom-color:var(--border)}
.nav-in{height:66px;display:flex;align-items:center;gap:34px}
.brand{display:inline-flex;align-items:center;gap:11px;flex-shrink:0}
.mark{width:30px;height:30px;border-radius:9px;display:grid;place-items:center;background:linear-gradient(145deg,#ff9c9c,#ef4444 55%,#c81e1e);box-shadow:0 4px 14px -4px rgba(239,68,68,.7)}
.mark svg{width:17px;height:17px;stroke:#fff}
.brand-name{font-size:15.5px;font-weight:600;letter-spacing:-.01em}
.brand-ver{font-family:var(--mono);font-size:10.5px;color:var(--mute);padding:1px 5px;border:1px solid var(--border);border-radius:5px;margin-left:-2px}
.nav-links{display:flex;gap:30px;font-size:14px;color:var(--dim);margin-left:auto}
.nav-links a{transition:color .2s}
.nav-links a:hover{color:#fff}

/* ---------- buttons ---------- */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:9px;height:48px;padding:0 24px;border-radius:11px;font-size:15px;font-weight:500;letter-spacing:-.005em;transition:transform .22s ease,background .22s ease,border-color .22s ease,box-shadow .22s ease;white-space:nowrap}
.btn svg{width:16px;height:16px}
.btn-solid{background:#f3f5fa;color:#0a0b0e;box-shadow:0 10px 26px -14px rgba(255,255,255,.5)}
.btn-solid:hover{background:#fff;transform:translateY(-1px);box-shadow:0 14px 30px -14px rgba(255,255,255,.55)}
.btn-accent{background:linear-gradient(180deg,#f65a5a,#c81e1e);color:#fff;box-shadow:0 12px 30px -12px rgba(200,30,30,.9),inset 0 1px 0 rgba(255,255,255,.22)}
.btn-accent:hover{background:linear-gradient(180deg,#ff6b6b,#dc2626);transform:translateY(-1px);box-shadow:0 16px 36px -12px rgba(220,38,38,.95)}
.btn-line{border:1px solid var(--border-2);color:var(--text);background:rgba(255,180,180,.03)}
.btn-line:hover{background:rgba(255,180,180,.09);border-color:rgba(255,180,180,.3)}

/* ---------- hero ---------- */
.hero{position:relative;padding:96px 0 0;text-align:center;isolation:isolate}
.hero::before{content:"";position:absolute;inset:-130px 0 auto;height:820px;z-index:-2;pointer-events:none;background:
  radial-gradient(50% 42% at 50% 6%,rgba(239,68,68,.24),transparent 72%),
  radial-gradient(32% 28% at 82% 16%,rgba(249,115,22,.1),transparent 70%),
  radial-gradient(30% 26% at 16% 22%,rgba(185,28,28,.16),transparent 72%)}
.hero::after{content:"";position:absolute;inset:-70px 0 auto;height:700px;z-index:-1;pointer-events:none;
  background-image:linear-gradient(rgba(255,214,214,.05) 1px,transparent 1px),linear-gradient(90deg,rgba(255,214,214,.05) 1px,transparent 1px);
  background-size:66px 66px;
  -webkit-mask-image:radial-gradient(62% 58% at 50% 30%,#000 6%,transparent 74%);
  mask-image:radial-gradient(62% 58% at 50% 30%,#000 6%,transparent 74%)}
h1{margin:30px auto 0;font-size:clamp(38px,6vw,68px);line-height:1.08;letter-spacing:-.045em;font-weight:650}
.grad{background:linear-gradient(102deg,#ffffff 4%,#ffc9c9 44%,#ff8a8a 96%);-webkit-background-clip:text;background-clip:text;color:transparent}
.lede{margin:24px auto 0;max-width:636px;font-size:16.5px;line-height:1.75;color:var(--dim);text-wrap:pretty}
.hero-actions{display:flex;justify-content:center;gap:12px;margin-top:34px;flex-wrap:wrap}
.hero-note{margin-top:18px;font-size:12.6px;color:var(--mute);letter-spacing:.01em}
.hero-note b{color:#c9b6ba;font-weight:500}

/* ---------- app screenshot（真实软件界面截图 · 下缘渐变遮罩虚化） ---------- */
.mock-wrap{position:relative;margin:58px auto 0;max-width:975px;isolation:isolate}
.mock-wrap::before{content:"";position:absolute;inset:8% 6% -10% 6%;z-index:-1;border-radius:50%;background:radial-gradient(50% 50% at 50% 50%,rgba(239,68,68,.26),transparent 72%);filter:blur(30px);pointer-events:none}
.shot{display:block;width:100%;height:auto;border-radius:14px;border:1px solid rgba(255,196,196,.1);background:#140e10;
  box-shadow:0 60px 110px -44px rgba(0,0,0,.95),0 0 0 6px rgba(255,180,180,.018);
  -webkit-mask-image:linear-gradient(180deg,#000 0,#000 56%,rgba(0,0,0,.72) 72%,rgba(0,0,0,.28) 88%,transparent 100%);
  mask-image:linear-gradient(180deg,#000 0,#000 56%,rgba(0,0,0,.72) 72%,rgba(0,0,0,.28) 88%,transparent 100%)}
/* 下缘渐进模糊：遮罩只让下半段的背景模糊生效，越往下越糊 */
.mock-wrap::after{content:"";position:absolute;left:0;right:0;bottom:0;height:46%;pointer-events:none;border-radius:0 0 14px 14px;
  -webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);
  -webkit-mask-image:linear-gradient(180deg,transparent 0,rgba(0,0,0,.45) 40%,#000 85%);
  mask-image:linear-gradient(180deg,transparent 0,rgba(0,0,0,.45) 40%,#000 85%)}

/* ---------- section ---------- */
.section{padding:66px 0}
.sec-head{display:flex;align-items:flex-end;justify-content:space-between;gap:28px;flex-wrap:wrap;margin-bottom:34px}
.sec-head h2{font-size:clamp(24px,3vw,31px);letter-spacing:-.032em;font-weight:600;line-height:1.25}
.sec-head p{margin-top:9px;font-size:14.5px;color:var(--dim);max-width:470px}
.sec-head.center{flex-direction:column;align-items:center;text-align:center;gap:0}
.sec-head.center p{max-width:none}
.eyebrow{font-family:var(--mono);font-size:11.5px;letter-spacing:.14em;color:var(--accent-lt);text-transform:uppercase;margin-bottom:12px}

/* ---------- features ---------- */
.features{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}
.feature{position:relative;padding:26px 24px;border:1px solid var(--border);border-radius:16px;background:linear-gradient(178deg,rgba(255,255,255,.04),rgba(255,255,255,.009));transition:border-color .3s,background .3s,transform .3s}
.feature:hover{border-color:rgba(255,255,255,.15);background:linear-gradient(178deg,rgba(255,255,255,.06),rgba(255,255,255,.014));transform:translateY(-3px)}
.f-ico{width:40px;height:40px;border-radius:11px;display:grid;place-items:center;border:1px solid rgba(239,68,68,.28);background:rgba(239,68,68,.1);margin-bottom:18px}
.f-ico svg{width:20px;height:20px;stroke:#ffa3a3;fill:none;stroke-width:1.6;stroke-linecap:round;stroke-linejoin:round}
.feature h3{font-size:15.5px;font-weight:600;letter-spacing:-.012em}
.feature p{margin-top:8px;font-size:13.6px;line-height:1.7;color:var(--dim);text-wrap:pretty}

/* ---------- steps + formats ---------- */
.split{display:grid;grid-template-columns:1.02fr .98fr;gap:40px;align-items:start}
.steps{display:flex;flex-direction:column;gap:2px}
.step{display:grid;grid-template-columns:44px 1fr;gap:18px;padding:20px 0;border-top:1px solid var(--border)}
.step:last-child{border-bottom:1px solid var(--border)}
.step .n{font-family:var(--mono);font-size:12px;color:var(--accent-lt);padding-top:2px}
.step h3{font-size:15.5px;font-weight:600;letter-spacing:-.012em}
.step p{margin-top:6px;font-size:13.6px;line-height:1.7;color:var(--dim)}
.fmt-card{padding:28px 26px;border:1px solid var(--border);border-radius:16px;background:linear-gradient(178deg,rgba(255,255,255,.04),rgba(255,255,255,.009))}
.fmt-card h3{font-size:15.5px;font-weight:600;letter-spacing:-.012em}
.fmt-card>p{margin-top:7px;font-size:13.4px;color:var(--dim);line-height:1.7}
.fmt-group{margin-top:22px}
.fmt-group .k{font-size:11.5px;letter-spacing:.08em;color:var(--mute);text-transform:uppercase;font-family:var(--mono)}
.tags{display:flex;flex-wrap:wrap;gap:7px;margin-top:10px}
.tags span{font-family:var(--mono);font-size:12px;color:#dcd0d3;padding:4.5px 10px;border-radius:7px;border:1px solid var(--border);background:rgba(255,255,255,.035)}
.tags span.hi{color:#ffb3b3;border-color:rgba(239,68,68,.36);background:rgba(239,68,68,.11)}

/* ---------- video tutorial（视频教程） ---------- */
.video-card{position:relative;margin:0;isolation:isolate}
.video-card::before{content:"";position:absolute;inset:6% 4% -7% 4%;z-index:-1;border-radius:50%;background:radial-gradient(50% 50% at 50% 50%,rgba(239,68,68,.28),transparent 72%);filter:blur(40px);pointer-events:none}
/* 宽度跟随 .wrap 满格；高度按画面比例自适应（1400/758 与 poster、源视频 1994×1080 同比例） */
.video{display:block;width:100%;height:auto;aspect-ratio:1400/758;border-radius:16px;border:1px solid rgba(255,196,196,.13);background:#0b0608;
  box-shadow:0 54px 104px -48px rgba(0,0,0,.95),0 0 0 6px rgba(255,180,180,.022)}
.video-card figcaption{margin-top:16px;text-align:center;font-size:12.6px;color:var(--mute);letter-spacing:.01em}

/* ---------- download cta ---------- */
.dl-box{position:relative;overflow:hidden;border:1px solid var(--border);border-radius:22px;padding:56px 40px 50px;text-align:center;background:linear-gradient(178deg,rgba(255,255,255,.05),rgba(255,255,255,.012))}
.dl-box::before{content:"";position:absolute;inset:auto 0 -60% 0;height:340px;background:radial-gradient(50% 100% at 50% 100%,rgba(239,68,68,.22),transparent 72%);pointer-events:none}
.dl-box h2{font-size:clamp(23px,3vw,30px);letter-spacing:-.032em;font-weight:600}
.dl-box p{margin-top:11px;font-size:14.6px;color:var(--dim)}
.dl-meta{display:flex;justify-content:center;gap:26px;margin-top:22px;font-size:12.4px;color:var(--mute);flex-wrap:wrap}
.dl-meta span{display:inline-flex;align-items:center;gap:6px}
.dl-meta i{width:4px;height:4px;border-radius:50%;background:#4d3a3e}

/* ---------- 网盘下载 ---------- */
.mirrors{display:flex;justify-content:center;gap:12px;margin-top:28px;flex-wrap:wrap}
.mirror{display:flex;align-items:center;gap:12px;min-width:224px;padding:12px 16px;border:1px solid var(--border-2);border-radius:13px;background:rgba(255,255,255,.035);text-align:left;transition:background .22s,border-color .22s,transform .22s,box-shadow .22s;position:relative;z-index:1}
.mirror:hover{background:rgba(255,255,255,.072);border-color:rgba(255,255,255,.26);transform:translateY(-1px);box-shadow:0 16px 34px -22px rgba(0,0,0,.9)}
.mirror .mi{width:34px;height:34px;border-radius:9.5px;display:grid;place-items:center;flex-shrink:0;border:1px solid rgba(239,68,68,.28);background:rgba(239,68,68,.1)}
.mirror .mi svg{width:17px;height:17px;stroke:#ffa3a3;fill:none;stroke-width:1.7;stroke-linecap:round;stroke-linejoin:round}
.mirror .mt{display:flex;flex-direction:column;gap:1px;min-width:0}
.mirror .mt b{font-size:14px;font-weight:600;letter-spacing:-.01em;line-height:1.35}
.mirror .mt span{font-size:11.6px;color:var(--mute);font-variant-numeric:tabular-nums;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.mirror .go{margin-left:auto;color:#94858a;transition:color .2s,transform .2s}
.mirror .go svg{width:14px;height:14px;stroke:currentColor;fill:none;stroke-width:1.9;stroke-linecap:round;stroke-linejoin:round}
.mirror:hover .go{color:#fff;transform:translate(1px,-1px)}
.mirror.off{opacity:.55}
.btn.off{opacity:.55}

/* ---------- footer ---------- */
.foot{margin-top:44px;border-top:1px solid var(--border);background:linear-gradient(180deg,rgba(255,255,255,.014),transparent)}
.foot-in{display:flex;justify-content:space-between;gap:56px;padding-top:52px;padding-bottom:44px;flex-wrap:wrap}
.foot-brand p{margin-top:14px;font-size:13.2px;color:var(--mute);max-width:270px;line-height:1.7}
.foot-cols{display:flex;gap:76px;flex-wrap:wrap}
.foot-cols h4{font-size:12.4px;font-weight:600;letter-spacing:.04em;color:#d6c8cb;margin-bottom:13px}
.foot-cols a{display:block;font-size:13.3px;color:var(--mute);padding:4.5px 0;transition:color .2s}
.foot-cols a:hover{color:var(--text)}
.foot-bot{display:flex;justify-content:space-between;gap:16px;padding-top:20px;padding-bottom:34px;border-top:1px solid var(--border);font-size:12.3px;color:#6e5f64;flex-wrap:wrap;line-height:1.7}
.foot-bot .legal{max-width:640px}

/* ---------- toast ---------- */
.toast{position:fixed;left:50%;bottom:34px;z-index:200;display:flex;align-items:center;gap:10px;padding:12px 18px;border-radius:11px;border:1px solid var(--border-2);background:rgba(26,16,18,.96);backdrop-filter:blur(12px);font-size:13.2px;color:#e4e9f2;box-shadow:0 22px 50px -18px rgba(0,0,0,1);opacity:0;transform:translate(-50%,14px);pointer-events:none;transition:opacity .26s,transform .26s}
.toast.show{opacity:1;transform:translate(-50%,0)}
.toast svg{width:15px;height:15px;stroke:#ff9b9b;flex-shrink:0;fill:none;stroke-width:2;stroke-linecap:round;stroke-linejoin:round}

/* ---------- reveal ---------- */
html.js .reveal{opacity:0;transform:translateY(18px);transition:opacity .65s cubic-bezier(.2,.7,.3,1),transform .65s cubic-bezier(.2,.7,.3,1)}
html.js .reveal.in{opacity:1;transform:none}

/* ---------- responsive ---------- */
@media (max-width:1080px){
  .nav-links{gap:24px}
  .features{grid-template-columns:repeat(2,1fr)}
  .split{grid-template-columns:1fr;gap:34px}
}
@media (max-width:880px){
  .wrap{padding:0 22px}
  .nav-links{display:none}
  .hero{padding:74px 0 0}
  .section{padding:54px 0}
  .mock-wrap{margin-top:42px}
  .dl-box{padding:44px 24px 40px}
  .foot-cols{gap:44px}
}
@media (max-width:600px){
  .wrap{padding:0 18px}
  h1{letter-spacing:-.035em}
  .lede{font-size:15.4px}
  .features{grid-template-columns:1fr}
  .hero-actions .btn{flex:1 1 148px}
  .mock-wrap{margin:34px 0 0}
  .mirrors{flex-direction:column;align-items:stretch;gap:10px;margin-top:24px}
  .mirror{min-width:0;width:100%}
  .dl-meta{gap:8px 18px}
  .dl-meta i{display:none}
  .foot-in{padding-top:40px;gap:34px}
  .foot-bot{flex-direction:column;gap:8px}
}
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation-duration:.01ms !important;transition-duration:.01ms !important}
  html.js .reveal{opacity:1;transform:none}
}