/* ============================================================
   三道门服务 · AI 原创内容创作平台
   设计系统 · 轻盈 / 干净 / 移动优先
   ============================================================ */
:root{
  --ink:#15171e;
  --ink-2:#4b5060;
  --ink-3:#8a8f9f;
  --bg:#f6f7fb;
  --card:#ffffff;
  --line:#e7e9f1;
  --brand:#4f46e5;
  --brand-2:#7c6cf6;
  --brand-soft:#eeedfd;
  --amber:#f59e0b;
  --ok:#10b981;
  --shadow-s:0 1px 2px rgba(21,23,30,.05),0 2px 10px rgba(21,23,30,.05);
  --shadow-m:0 6px 24px rgba(21,23,30,.09);
  --radius:16px;
  --maxw:1120px;
}
*{box-sizing:border-box;margin:0;padding:0}
html{-webkit-text-size-adjust:100%}
body{
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  color:var(--ink);background:var(--bg);
  line-height:1.6;font-size:16px;
}
a{color:inherit;text-decoration:none}
img,svg,video{display:block;max-width:100%}
button{font-family:inherit;cursor:pointer;border:0;background:none}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 20px}

/* ---------- header ---------- */
.site-header{
  position:sticky;top:0;z-index:50;
  background:rgba(246,247,251,.86);
  backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);
  border-bottom:1px solid var(--line);
}
.site-header .wrap{display:flex;align-items:center;gap:28px;height:64px}
.brand{display:flex;align-items:center;gap:10px;flex-shrink:0}
.brand .name{font-size:19px;font-weight:800;letter-spacing:.5px}
.brand .name small{display:block;font-size:11px;font-weight:500;color:var(--ink-3);letter-spacing:2px;line-height:1;margin-top:2px}
.main-nav{display:flex;gap:6px;margin-left:auto}
.main-nav a{
  padding:8px 14px;border-radius:10px;font-size:15px;color:var(--ink-2);
  transition:background .15s,color .15s;
}
.main-nav a:hover{background:#eceef6;color:var(--ink)}
.main-nav a.active{background:var(--brand-soft);color:var(--brand);font-weight:600}
.header-cta{flex-shrink:0}
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  padding:10px 20px;border-radius:12px;font-size:15px;font-weight:600;
  transition:transform .15s,box-shadow .15s,background .15s;
  white-space:nowrap;
}
.btn:active{transform:scale(.97)}
.btn-primary{background:var(--brand);color:#fff;box-shadow:0 6px 16px rgba(79,70,229,.28)}
.btn-primary:hover{background:#4338ca}
.btn-ghost{background:#fff;color:var(--ink);border:1px solid var(--line);box-shadow:var(--shadow-s)}
.btn-ghost:hover{border-color:#d5d8e6}
.btn-lg{padding:14px 30px;font-size:17px;border-radius:14px}

/* mobile nav */
.nav-toggle{display:none;margin-left:auto;width:40px;height:40px;border-radius:10px;align-items:center;justify-content:center}
.nav-toggle svg{width:22px;height:22px}
@media (max-width:820px){
  .main-nav{
    display:none;position:absolute;top:64px;left:0;right:0;
    background:#fff;border-bottom:1px solid var(--line);
    flex-direction:column;padding:10px 14px 14px;gap:2px;
    box-shadow:var(--shadow-m);
  }
  .main-nav.open{display:flex}
  .main-nav a{padding:12px 14px;font-size:16px}
  .nav-toggle{display:inline-flex}
  .header-cta{display:none}
}

/* ---------- hero ---------- */
.hero{position:relative;overflow:hidden;padding:72px 0 64px}
.hero-bg{
  position:absolute;inset:0;pointer-events:none;
  background:
    radial-gradient(560px 320px at 12% 8%,rgba(124,108,246,.14),transparent 60%),
    radial-gradient(640px 360px at 88% 20%,rgba(79,70,229,.10),transparent 60%),
    radial-gradient(520px 300px at 55% 100%,rgba(245,158,11,.07),transparent 60%);
}
.hero .wrap{position:relative;display:grid;grid-template-columns:1.1fr .9fr;gap:48px;align-items:center}
.hero-kicker{
  display:inline-flex;align-items:center;gap:8px;
  background:#fff;border:1px solid var(--line);border-radius:999px;
  padding:6px 14px;font-size:13px;color:var(--ink-2);box-shadow:var(--shadow-s);
}
.hero-kicker .dot{width:7px;height:7px;border-radius:50%;background:var(--ok)}
.hero h1{
  margin:22px 0 16px;font-size:clamp(30px,4.6vw,46px);
  line-height:1.22;font-weight:800;letter-spacing:.5px;
}
.hero h1 .accent{
  background:linear-gradient(100deg,var(--brand),var(--brand-2));
  -webkit-background-clip:text;background-clip:text;color:transparent;
}
.hero p.lead{font-size:17px;color:var(--ink-2);max-width:32em}
.hero-actions{display:flex;gap:14px;margin-top:30px;flex-wrap:wrap}
.hero-note{margin-top:14px;font-size:13px;color:var(--ink-3)}
.hero-art{position:relative}

@media (max-width:820px){
  .hero{padding:48px 0 40px}
  .hero .wrap{grid-template-columns:1fr;gap:36px}
  .hero-art{order:-1}
  .hero-art svg{max-height:220px;margin:0 auto}
}

/* ---------- sections ---------- */
.section{padding:64px 0}
.section.tight{padding:40px 0}
.section-head{display:flex;align-items:flex-end;justify-content:space-between;gap:20px;margin-bottom:32px}
.section-head h2{font-size:clamp(22px,3vw,30px);font-weight:800;letter-spacing:.5px}
.section-head .sub{color:var(--ink-2);margin-top:8px;font-size:15px;max-width:36em}
.section-head .more{color:var(--brand);font-weight:600;font-size:15px;flex-shrink:0;padding-bottom:4px}
.section-head .more:hover{text-decoration:underline}

/* three doors */
.doors{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.door-card{
  background:var(--card);border:1px solid var(--line);border-radius:var(--radius);
  padding:28px 26px;box-shadow:var(--shadow-s);
  transition:transform .2s,box-shadow .2s;
}
.door-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-m)}
.door-card .glyph{width:52px;height:52px;border-radius:14px;display:flex;align-items:center;justify-content:center;margin-bottom:18px}
.door-card .glyph svg{width:28px;height:28px}
.glyph.g1{background:var(--brand-soft);color:var(--brand)}
.glyph.g2{background:#fdf3e3;color:#d97706}
.glyph.g3{background:#e7f6f1;color:#0d9488}
.door-card h3{font-size:19px;font-weight:700;margin-bottom:8px}
.door-card p{font-size:14.5px;color:var(--ink-2)}
.door-card .num{float:right;font-size:13px;color:var(--ink-3);font-weight:700;letter-spacing:1px}
@media (max-width:820px){.doors{grid-template-columns:1fr}}

/* tools */
.tools-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.tool-card{
  background:var(--card);border:1px solid var(--line);border-radius:var(--radius);
  padding:24px;box-shadow:var(--shadow-s);display:flex;flex-direction:column;gap:12px;
  transition:transform .2s,box-shadow .2s;
}
.tool-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-m)}
.tool-top{display:flex;align-items:center;gap:12px}
.tool-ico{width:44px;height:44px;border-radius:12px;display:flex;align-items:center;justify-content:center;background:var(--brand-soft);color:var(--brand)}
.tool-ico svg{width:22px;height:22px}
.tool-card h3{font-size:17px;font-weight:700}
.tool-card p{font-size:14px;color:var(--ink-2);flex:1}
.tool-card .go{color:var(--brand);font-weight:600;font-size:14.5px;display:inline-flex;align-items:center;gap:6px}
@media (max-width:1020px){.tools-grid{grid-template-columns:repeat(2,1fr)}}
@media (max-width:620px){.tools-grid{grid-template-columns:1fr}}

/* works */
.works-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}
.work-card{
  background:var(--card);border:1px solid var(--line);border-radius:var(--radius);
  overflow:hidden;box-shadow:var(--shadow-s);
  transition:transform .2s,box-shadow .2s;display:block;
}
.work-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-m)}
.work-thumb{position:relative;aspect-ratio:9/14;background:#e9ebf3;overflow:hidden}
.work-thumb img,.work-thumb video{width:100%;height:100%;object-fit:cover}
.work-thumb .play{
  position:absolute;inset:0;display:flex;align-items:center;justify-content:center;
}
.work-thumb .play span{
  width:52px;height:52px;border-radius:50%;background:rgba(21,23,30,.55);
  display:flex;align-items:center;justify-content:center;backdrop-filter:blur(4px);
}
.work-thumb .play svg{width:20px;height:20px;color:#fff;margin-left:3px}
.badge-ai{
  position:absolute;top:10px;left:10px;z-index:2;
  background:rgba(21,23,30,.62);color:#fff;backdrop-filter:blur(4px);
  font-size:11px;padding:4px 9px;border-radius:999px;letter-spacing:1px;
}
.work-meta{padding:14px 16px 16px}
.work-meta h3{font-size:15.5px;font-weight:700;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.work-meta .row{display:flex;align-items:center;justify-content:space-between;margin-top:6px}
.work-meta .tool{font-size:12.5px;color:var(--brand);background:var(--brand-soft);padding:3px 9px;border-radius:999px}
.work-meta .date{font-size:12px;color:var(--ink-3)}
@media (max-width:1020px){.works-grid{grid-template-columns:repeat(2,1fr)}}
@media (max-width:520px){.works-grid{grid-template-columns:repeat(2,1fr);gap:12px}.work-meta{padding:10px 12px 12px}.work-meta h3{font-size:13.5px}}

/* share steps */
.share-band{
  background:linear-gradient(135deg,#1b1d2b 0%,#23264a 55%,#2c2560 100%);
  border-radius:24px;color:#fff;padding:52px 48px;position:relative;overflow:hidden;
}
.share-band::after{
  content:"";position:absolute;right:-80px;top:-80px;width:320px;height:320px;border-radius:50%;
  background:radial-gradient(closest-side,rgba(124,108,246,.35),transparent);
}
.share-band h2{font-size:clamp(22px,3vw,30px);font-weight:800;letter-spacing:.5px}
.share-band p.sub{color:#b6bad2;margin-top:10px;font-size:15px;max-width:34em}
.share-steps{display:grid;grid-template-columns:repeat(3,1fr);gap:18px;margin-top:34px;position:relative;z-index:1}
.share-step{background:rgba(255,255,255,.07);border:1px solid rgba(255,255,255,.12);border-radius:16px;padding:22px}
.share-step .n{
  width:30px;height:30px;border-radius:10px;background:rgba(124,108,246,.35);
  display:flex;align-items:center;justify-content:center;font-weight:800;font-size:14px;margin-bottom:14px;
}
.share-step h3{font-size:16px;font-weight:700}
.share-step p{font-size:13.5px;color:#c6c9dd;margin-top:6px}
.share-band .fine{margin-top:26px;font-size:12.5px;color:#8f93ad;position:relative;z-index:1}
@media (max-width:820px){.share-band{padding:36px 24px}.share-steps{grid-template-columns:1fr}}

/* ---------- work detail (H5) ---------- */
.detail-wrap{max-width:520px;margin:0 auto;padding:18px 16px 40px}
.back-link{display:inline-flex;align-items:center;gap:6px;color:var(--ink-2);font-size:14px;margin-bottom:14px}
.detail-media{
  border-radius:20px;overflow:hidden;background:#101219;
  box-shadow:var(--shadow-m);position:relative;
}
.detail-media img,.detail-media video{width:100%;max-height:74vh;object-fit:contain;background:#101219}
.detail-head{display:flex;align-items:flex-start;gap:10px;margin-top:18px}
.detail-head h1{font-size:20px;font-weight:800;line-height:1.35;flex:1}
.detail-sub{display:flex;flex-wrap:wrap;gap:8px;align-items:center;margin-top:10px}
.pill{font-size:12.5px;padding:4px 11px;border-radius:999px;background:#eceef6;color:var(--ink-2)}
.pill.brand{background:var(--brand-soft);color:var(--brand);font-weight:600}
.pill.ai{background:#fdf3e3;color:#b45309}
.detail-desc{margin-top:14px;font-size:14.5px;color:var(--ink-2)}
.share-cta{margin-top:26px;display:flex;flex-direction:column;gap:12px}
.share-confirm{
  display:flex;align-items:flex-start;gap:10px;padding:13px 14px;
  border:1px solid var(--line);border-radius:14px;background:#f8f9fc;
  color:var(--ink-2);font-size:13px;line-height:1.6;text-align:left;
}
.share-confirm input{width:18px;height:18px;margin-top:1px;flex:0 0 auto;accent-color:var(--brand)}
.btn-douyin{
  width:100%;padding:16px;border-radius:16px;
  background:#161823;color:#fff;font-size:17px;font-weight:700;
  display:flex;align-items:center;justify-content:center;gap:10px;
  box-shadow:0 10px 24px rgba(22,24,35,.28);
}
.btn-douyin:disabled{opacity:.45;cursor:not-allowed;box-shadow:none}
.btn-douyin:active{transform:scale(.98)}
.btn-douyin svg{width:22px;height:22px}
.btn-save{
  width:100%;padding:14px;border-radius:16px;
  background:#fff;border:1px solid var(--line);color:var(--ink);
  font-size:15.5px;font-weight:600;display:flex;align-items:center;justify-content:center;gap:8px;
}
.share-tip{margin-top:14px;font-size:12.5px;color:var(--ink-3);text-align:center;line-height:1.7}

/* PC qr panel */
.qr-panel{
  margin-top:22px;background:var(--card);border:1px solid var(--line);
  border-radius:18px;padding:24px;text-align:center;box-shadow:var(--shadow-s);
}
.qr-panel h3{font-size:16px;font-weight:700}
.qr-panel p{font-size:13px;color:var(--ink-2);margin-top:6px}
.qr-box{margin:16px auto 0;width:184px;height:184px;padding:12px;background:#fff;border:1px solid var(--line);border-radius:14px}
.qr-box svg{width:100%;height:100%}
.qr-fallback{margin-top:12px;font-size:12px;color:var(--ink-3);word-break:break-all}

/* modal */
.modal-mask{
  position:fixed;inset:0;z-index:100;background:rgba(15,17,26,.5);
  display:none;align-items:center;justify-content:center;padding:20px;
  backdrop-filter:blur(3px);-webkit-backdrop-filter:blur(3px);
}
.modal-mask.show{display:flex}
.modal{
  background:#fff;border-radius:20px;max-width:360px;width:100%;
  padding:28px 24px 22px;text-align:center;
  animation:pop .18s ease-out;
}
@keyframes pop{from{transform:scale(.94);opacity:0}to{transform:scale(1);opacity:1}}
.modal .ico{width:56px;height:56px;border-radius:18px;background:var(--brand-soft);color:var(--brand);display:flex;align-items:center;justify-content:center;margin:0 auto 16px}
.modal .ico svg{width:28px;height:28px}
.modal h3{font-size:18px;font-weight:800}
.modal p{font-size:14px;color:var(--ink-2);margin-top:10px}
.modal .acts{display:flex;flex-direction:column;gap:10px;margin-top:22px}
.modal .acts .btn{width:100%}
.modal .later{font-size:13px;color:var(--ink-3);padding:8px}

/* toast */
.toast{
  position:fixed;left:50%;bottom:48px;transform:translateX(-50%) translateY(20px);
  background:rgba(21,23,30,.92);color:#fff;font-size:14px;
  padding:11px 20px;border-radius:12px;z-index:120;opacity:0;pointer-events:none;
  transition:all .25s;max-width:86vw;text-align:center;
}
.toast.show{opacity:1;transform:translateX(-50%) translateY(0)}

/* empty state */
.empty{
  text-align:center;padding:80px 20px;color:var(--ink-2);
}
.empty .ico{width:64px;height:64px;margin:0 auto 18px;border-radius:20px;background:#eceef6;display:flex;align-items:center;justify-content:center;color:var(--ink-3)}
.empty h3{font-size:18px;color:var(--ink)}
.empty p{font-size:14px;margin-top:8px}

/* ---------- about ---------- */
.prose{max-width:720px}
.prose h2{font-size:22px;font-weight:800;margin:36px 0 14px}
.prose h2:first-child{margin-top:0}
.prose p{color:var(--ink-2);margin-bottom:12px;font-size:15.5px}
.prose ul{color:var(--ink-2);padding-left:20px;margin-bottom:12px}
.prose li{margin-bottom:6px}
.value-cards{display:grid;grid-template-columns:repeat(3,1fr);gap:18px;margin-top:28px}
.value-card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:22px;box-shadow:var(--shadow-s)}
.value-card h3{font-size:16px;font-weight:700;margin-bottom:8px}
.value-card p{font-size:13.5px;color:var(--ink-2)}
@media (max-width:820px){.value-cards{grid-template-columns:1fr}}

/* ---------- footer ---------- */
.site-footer{border-top:1px solid var(--line);background:#fff;margin-top:40px}
.site-footer .top{display:flex;justify-content:space-between;gap:32px;padding:44px 0 36px;flex-wrap:wrap}
.site-footer .f-brand{max-width:300px}
.site-footer .f-brand p{font-size:13.5px;color:var(--ink-2);margin-top:12px}
.site-footer .cols{display:flex;gap:64px;flex-wrap:wrap}
.site-footer .col h4{font-size:14px;font-weight:700;margin-bottom:12px;color:var(--ink)}
.site-footer .col a{display:block;font-size:13.5px;color:var(--ink-2);margin-bottom:8px}
.site-footer .col a:hover{color:var(--brand)}
.site-footer .bottom{
  border-top:1px solid var(--line);padding:18px 0;
  font-size:12.5px;color:var(--ink-3);
  display:flex;justify-content:space-between;gap:10px;flex-wrap:wrap;
}
.site-footer .bottom a{color:var(--ink-2)}
.site-footer .bottom a:hover{color:var(--brand)}
@media (max-width:620px){.site-footer .cols{gap:32px}}

/* ---------- policy and review ---------- */
.policy-page h1,.review-hero h1{font-size:clamp(28px,4vw,40px);font-weight:800;line-height:1.2}
.policy-date{margin-top:8px;color:var(--ink-3)!important;font-size:13px!important}
.review-layout{max-width:960px}
.review-hero{padding:12px 0 28px;border-bottom:1px solid var(--line)}
.review-hero>span{color:var(--brand);font-size:12px;font-weight:800;letter-spacing:1px}
.review-hero p{max-width:680px;margin-top:12px;color:var(--ink-2);font-size:16px}
.review-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:16px;margin-top:26px}
.review-card{border:1px solid var(--line);border-radius:var(--radius);padding:22px;background:var(--card);box-shadow:var(--shadow-s)}
.review-card b{color:var(--brand);font-size:12px}
.review-card h2{font-size:17px;margin:10px 0 8px}
.review-card p{color:var(--ink-2);font-size:14px}
.review-path,.review-boundary{margin-top:24px;border:1px solid var(--line);border-radius:var(--radius);padding:24px;background:#fff}
.review-path h2,.review-boundary h2{font-size:19px;margin-bottom:14px}
.review-path ol{padding-left:22px;color:var(--ink-2)}
.review-path li{margin:8px 0}
.review-actions{display:flex;gap:12px;flex-wrap:wrap;margin-top:20px}
.review-boundary>div{display:flex;gap:9px;flex-wrap:wrap}
.review-boundary-copy{margin:-3px 0 16px;color:var(--ink-2);font-size:14px;line-height:1.75}
.review-boundary span{padding:7px 10px;border:1px solid var(--line);background:#f8f9fc;border-radius:8px;font-size:13px;color:var(--ink-2)}
.review-contact{margin-top:20px;color:var(--ink-3);font-size:13px}
@media (max-width:680px){.review-grid{grid-template-columns:1fr}}

/* helpers */
.center{text-align:center}
.mt-8{margin-top:8px}.mt-16{margin-top:16px}.mt-24{margin-top:24px}.mt-40{margin-top:40px}
.hidden{display:none!important}