:root{
    --ink:#1c0e0e;
    --ink-soft:#5b4242;
    --mist:#fdf6f5;
    --line:#f2e3e1;
    --brand:#d92b2b;
    --brand-deep:#9e1b1b;
    --brand-glow:rgba(217,43,43,.12);
    --accent:#ff7a45;
    --warm:#ff9f43;
    --green:#1f9d55;
    --blue:#2f6feb;
    --purple:#7c4dff;
    --teal:#12b3a6;
    --radius:18px;
    --shadow:0 12px 32px rgba(60,15,15,.08);
    --maxw:1180px;
  }
  *{box-sizing:border-box;}
  html{scroll-behavior:smooth;}
  body{
    margin:0;
    font-family:"PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,sans-serif;
    color:var(--ink);
    background:
      radial-gradient(1100px 520px at 82% -12%, rgba(255,122,69,.12), transparent 62%),
      radial-gradient(900px 460px at -8% 4%, rgba(217,43,43,.14), transparent 60%),
      #fdfbfb;
    line-height:1.78;
    -webkit-font-smoothing:antialiased;
  }
  a{color:inherit;text-decoration:none;}
  .wrap{max-width:var(--maxw);margin:0 auto;padding:0 22px;}

  /* ============ 顶部导航 ============ */
  .topbar{
    position:sticky;top:0;z-index:80;
    backdrop-filter:blur(16px);
    background:rgba(253,251,251,.84);
    border-bottom:1px solid var(--line);
  }
  .topbar-in{
    max-width:var(--maxw);margin:0 auto;padding:14px 22px;
    display:flex;align-items:center;gap:28px;
  }
  .logo{display:flex;align-items:center;gap:10px;font-weight:800;font-size:19px;letter-spacing:.4px;}
  .logo-mark{
    width:32px;height:32px;border-radius:10px;
    background:linear-gradient(135deg,var(--brand),var(--accent));
    display:grid;place-items:center;color:#fff;font-size:15px;font-weight:900;
    box-shadow:0 6px 16px var(--brand-glow);
  }
  .logo small{display:block;font-size:10px;font-weight:600;color:var(--ink-soft);letter-spacing:1.6px;line-height:1;}
  .nav{display:flex;gap:6px;margin-left:auto;flex-wrap:wrap;}
  .nav a{padding:9px 14px;border-radius:10px;font-size:14.5px;font-weight:600;color:var(--ink-soft);transition:.22s;}
  .nav a:hover{background:var(--brand-glow);color:var(--brand-deep);}
  .nav a.hot{background:var(--ink);color:#fff;}
  .nav a.hot:hover{background:var(--brand-deep);}

  /* ============ 通用 ============ */
  section{padding:74px 0;}
  .sec-head{max-width:760px;margin-bottom:42px;}
  .eyebrow{
    display:inline-flex;align-items:center;gap:8px;
    font-size:12.5px;font-weight:800;letter-spacing:2px;
    color:var(--brand-deep);text-transform:uppercase;
    padding:6px 14px;border-radius:999px;
    background:var(--brand-glow);margin-bottom:16px;
  }
  h1{font-size:clamp(30px,4.6vw,50px);line-height:1.22;margin:0 0 18px;letter-spacing:-.8px;}
  h2{font-size:clamp(23px,3vw,34px);line-height:1.3;margin:0 0 14px;letter-spacing:-.5px;}
  h3{font-size:19px;margin:0 0 10px;letter-spacing:-.2px;}
  p{margin:0 0 14px;color:var(--ink-soft);}
  .lead{font-size:17.5px;color:var(--ink-soft);max-width:760px;}
  .grid{display:grid;gap:22px;}
  .g2{grid-template-columns:repeat(2,1fr);}
  .g3{grid-template-columns:repeat(3,1fr);}
  .g4{grid-template-columns:repeat(4,1fr);}
  @media(max-width:960px){.g3,.g4{grid-template-columns:repeat(2,1fr);}}
  @media(max-width:680px){.g2,.g3,.g4{grid-template-columns:1fr;}.nav a{padding:7px 10px;font-size:13.5px;}}

  .card{
    background:#fff;border:1px solid var(--line);border-radius:var(--radius);
    padding:26px;box-shadow:var(--shadow);transition:.26s;
  }
  .card:hover{transform:translateY(-4px);border-color:#f7ccc7;}
  .card .ico{
    width:44px;height:44px;border-radius:13px;display:grid;place-items:center;
    font-size:20px;margin-bottom:14px;
    background:linear-gradient(135deg,rgba(217,43,43,.14),rgba(255,122,69,.18));
  }
  .card p:last-child{margin-bottom:0;}

  .note{
    border-left:4px solid var(--accent);background:rgba(255,122,69,.08);
    padding:16px 20px;border-radius:0 12px 12px 0;margin:20px 0;font-size:14.6px;
  }
  .note.warn{border-left-color:var(--brand);background:rgba(217,43,43,.07);}
  .note.tip{border-left-color:var(--green);background:rgba(31,157,85,.07);}
  .note b{color:var(--ink);}

  .tablewrap{overflow-x:auto;margin:18px 0 26px;}
  table{width:100%;border-collapse:collapse;font-size:14.4px;min-width:640px;}
  th,td{padding:14px 16px;text-align:left;border-bottom:1px solid var(--line);vertical-align:top;}
  th{background:var(--mist);font-weight:800;color:var(--ink);font-size:13.5px;}
  td{color:var(--ink-soft);}

  .crumb{font-size:13px;color:var(--ink-soft);margin-bottom:20px;}
  .crumb a{color:var(--brand-deep);font-weight:600;}

  /* ============ 断线保护 Hero ============ */
  .ks-hero{
    padding:78px 0 64px;
    position:relative;overflow:hidden;
  }
  .ks-hero::after{
    content:"";position:absolute;right:-180px;top:-110px;width:580px;height:580px;
    border-radius:50%;
    background:conic-gradient(from 220deg,rgba(217,43,43,.16),rgba(31,157,85,.14),rgba(47,111,235,.08),transparent 75%);
    filter:blur(8px);z-index:-1;
  }
  .ks-hero-in{display:grid;grid-template-columns:1.05fr .95fr;gap:52px;align-items:center;}
  @media(max-width:940px){.ks-hero-in{grid-template-columns:1fr;gap:36px;}}

  /* 状态对比面板 */
  .ks-panel{
    background:#fff;border:1px solid var(--line);border-radius:24px;
    padding:28px;box-shadow:0 22px 54px rgba(60,15,15,.11);
  }
  .ks-panel h4{
    margin:0 0 20px;font-size:12.5px;letter-spacing:2px;
    color:var(--ink-soft);text-transform:uppercase;font-weight:800;
  }
  .ks-two{
    display:grid;grid-template-columns:1fr 1fr;gap:14px;
  }
  .ks-col{
    padding:20px 18px;border-radius:16px;
    border:1px solid var(--line);
  }
  .ks-col.on{
    background:linear-gradient(135deg,rgba(31,157,85,.08),rgba(47,181,107,.06));
    border-color:rgba(31,157,85,.18);
  }
  .ks-col.off{
    background:linear-gradient(135deg,rgba(217,43,43,.08),rgba(255,122,69,.06));
    border-color:rgba(217,43,43,.18);
  }
  .ks-col .kc-hd{
    display:flex;align-items:center;gap:10px;margin-bottom:12px;
  }
  .ks-col .kc-ico{
    width:34px;height:34px;border-radius:11px;
    display:grid;place-items:center;font-size:16px;color:#fff;
  }
  .ks-col.on .kc-ico{background:linear-gradient(135deg,var(--green),#2fb56b);}
  .ks-col.off .kc-ico{background:linear-gradient(135deg,var(--brand),var(--accent));}
  .ks-col .kc-hd b{font-size:15.4px;}
  .ks-col ul{
    list-style:none;padding:0;margin:0;
    display:grid;gap:7px;
  }
  .ks-col ul li{
    font-size:12.8px;color:var(--ink-soft);line-height:1.6;
    display:flex;gap:7px;align-items:flex-start;
  }
  .ks-col ul li::before{
    content:"·";font-weight:900;flex:0 0 auto;
  }
  .ks-col.on ul li::before{color:var(--green);}
  .ks-col.off ul li::before{color:var(--brand);}
  .ks-foot{
    margin-top:18px;padding:14px 17px;border-radius:13px;
    background:linear-gradient(120deg,#2a1010,#4c1c1c);color:#f3cfc9;font-size:13.2px;
  }
  .ks-foot b{color:#fff;}

  /* ============ 索引导航 ============ */
  .ks-index{background:#fff;border-top:1px solid var(--line);border-bottom:1px solid var(--line);padding:56px 0;}
  .ks-index-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:14px;}
  @media(max-width:960px){.ks-index-grid{grid-template-columns:repeat(3,1fr);}}
  @media(max-width:560px){.ks-index-grid{grid-template-columns:repeat(2,1fr);}}
  .ks-index-item{
    display:flex;flex-direction:column;gap:8px;
    padding:20px 16px;border-radius:16px;
    border:1px solid var(--line);background:var(--mist);
    transition:.24s;text-align:center;
  }
  .ks-index-item:hover{background:#fff;border-color:#f7ccc7;transform:translateY(-3px);box-shadow:var(--shadow);}
  .ks-index-item .ki-ico{font-size:26px;}
  .ks-index-item .ki-name{font-size:14px;font-weight:800;color:var(--ink);}
  .ks-index-item .ki-sub{font-size:11.4px;color:#a08b8b;font-weight:600;line-height:1.5;}

  /* ============ 内容板块 ============ */
  .ks-section{padding:74px 0;}
  .ks-section.alt{background:#fff;border-top:1px solid var(--line);border-bottom:1px solid var(--line);}
  .ks-section.dark{
    background:linear-gradient(160deg,#1c0e0e 0%,#331414 100%);
    color:#f3cfc9;
  }
  .ks-section.dark .eyebrow{background:rgba(255,180,168,.12);color:#ffb4a8;}
  .ks-section.dark h2{color:#fff;}
  .ks-section.dark .lead{color:#d8b3ae;}
  .ks-section.dark p{color:#d8b3ae;}
  .ks-section.dark .note{background:rgba(255,122,69,.12);color:#f3cfc9;}
  .ks-section.dark .note b{color:#fff;}

  .ks-block-head{
    display:flex;align-items:flex-start;gap:20px;margin-bottom:36px;
  }
  .ks-block-head .kb-num{
    flex:0 0 auto;
    width:64px;height:64px;border-radius:20px;
    display:grid;place-items:center;
    font-size:24px;font-weight:900;color:#fff;
    background:linear-gradient(135deg,var(--brand),var(--accent));
    box-shadow:0 14px 30px var(--brand-glow);
    letter-spacing:-1px;
  }
  .ks-block-head .kb-txt{flex:1;}
  .ks-block-head .kb-txt h2{margin-bottom:8px;}

  /* 场景卡片 */
  .scene-card{
    background:#fff;border:1px solid var(--line);border-radius:20px;
    padding:28px;transition:.26s;position:relative;overflow:hidden;
  }
  .scene-card:hover{transform:translateY(-4px);border-color:#f7ccc7;box-shadow:var(--shadow);}
  .scene-card .sc-strip{
    position:absolute;left:0;top:0;width:100%;height:4px;
    background:linear-gradient(90deg,var(--brand),var(--accent));
  }
  .scene-card.warm .sc-strip{background:linear-gradient(90deg,var(--warm),#e07b1a);}
  .scene-card.blue .sc-strip{background:linear-gradient(90deg,var(--blue),#4dabf7);}
  .scene-card .sc-hd{
    display:flex;align-items:center;gap:13px;margin-bottom:14px;
  }
  .scene-card .sc-ico{
    flex:0 0 auto;width:48px;height:48px;border-radius:15px;
    display:grid;place-items:center;font-size:22px;
    background:linear-gradient(135deg,rgba(217,43,43,.14),rgba(255,122,69,.2));
  }
  .scene-card.warm .sc-ico{background:linear-gradient(135deg,rgba(255,159,67,.18),rgba(224,123,26,.16));}
  .scene-card.blue .sc-ico{background:linear-gradient(135deg,rgba(47,111,235,.14),rgba(77,171,247,.2));}
  .scene-card .sc-name{font-size:17px;font-weight:800;letter-spacing:-.2px;}
  .scene-card p{font-size:14.3px;}
  .scene-card .sc-when{
    margin-top:14px;padding:12px 15px;border-radius:12px;
    background:var(--mist);border:1px solid var(--line);
    font-size:13.2px;color:var(--ink-soft);line-height:1.65;
  }
  .scene-card .sc-when b{color:var(--ink);}

  /* 工作原理步骤 */
  .work-steps{
    display:grid;grid-template-columns:repeat(3,1fr);gap:22px;
    counter-reset:wstep;
  }
  @media(max-width:900px){.work-steps{grid-template-columns:1fr;}}
  .ws-card{
    position:relative;background:#fff;border:1px solid var(--line);
    border-radius:var(--radius);padding:28px 26px 26px 76px;
    box-shadow:var(--shadow);transition:.26s;
  }
  .ws-card:hover{transform:translateY(-4px);border-color:#f7ccc7;}
  .ws-card::before{
    counter-increment:wstep;content:counter(wstep,decimal-leading-zero);
    position:absolute;left:24px;top:26px;
    width:34px;height:34px;border-radius:11px;
    display:grid;place-items:center;
    font-size:13px;font-weight:900;color:#fff;letter-spacing:.5px;
    background:linear-gradient(135deg,var(--brand),var(--accent));
    box-shadow:0 6px 14px var(--brand-glow);
  }
  .ws-card h3{margin-bottom:6px;font-size:17px;}
  .ws-card p:last-child{margin-bottom:0;font-size:14.4px;}

  /* 模式对比 */
  .mode-two{
    display:grid;grid-template-columns:1fr 1fr;gap:22px;
  }
  @media(max-width:760px){.mode-two{grid-template-columns:1fr;}}
  .mode-card{
    padding:30px;border-radius:20px;
    background:rgba(255,255,255,.06);
    border:1px solid rgba(255,180,168,.16);
    transition:.26s;
  }
  .mode-card:hover{background:rgba(255,180,168,.1);border-color:rgba(255,180,168,.34);transform:translateY(-4px);}
  .mode-card .mc-badge{
    display:inline-flex;align-items:center;gap:6px;
    font-size:11.8px;font-weight:900;letter-spacing:.8px;
    padding:5px 13px;border-radius:999px;
    margin-bottom:14px;
  }
  .mode-card.strict .mc-badge{background:rgba(217,43,43,.2);color:#ffb4a8;}
  .mode-card.loose .mc-badge{background:rgba(47,111,235,.2);color:#a8c8ff;}
  .mode-card h4{font-size:19px;color:#fff;margin:0 0 10px;font-weight:800;}
  .mode-card p{font-size:14.2px;color:#d8b3ae;margin-bottom:12px;}
  .mode-card p:last-child{margin-bottom:0;}
  .mode-card .mc-list{
    list-style:none;padding:0;margin:14px 0 0;
    display:grid;gap:8px;
  }
  .mode-card .mc-list li{
    display:flex;gap:9px;align-items:flex-start;
    font-size:13.4px;color:#d8b3ae;line-height:1.6;
  }
  .mode-card .mc-list li::before{
    content:"—";font-weight:900;flex:0 0 auto;
  }
  .mode-card.strict .mc-list li::before{color:#ffb4a8;}
  .mode-card.loose .mc-list li::before{color:#a8c8ff;}

  /* 验证步骤 */
  .verify-steps{
    display:grid;grid-template-columns:repeat(5,1fr);gap:14px;
    counter-reset:vstep;
  }
  @media(max-width:960px){.verify-steps{grid-template-columns:repeat(3,1fr);}}
  @media(max-width:560px){.verify-steps{grid-template-columns:repeat(2,1fr);}}
  .vs-card{
    position:relative;background:#fff;border:1px solid var(--line);
    border-radius:16px;padding:24px 18px 20px;
    box-shadow:var(--shadow);transition:.26s;
    counter-increment:vstep;
  }
  .vs-card:hover{transform:translateY(-4px);border-color:#f7ccc7;}
  .vs-card::before{
    content:counter(vstep,decimal-leading-zero);
    display:inline-flex;
    width:34px;height:34px;border-radius:11px;
    align-items:center;justify-content:center;
    font-size:13px;font-weight:900;color:#fff;letter-spacing:.5px;
    background:linear-gradient(135deg,var(--green),#2fb56b);
    box-shadow:0 6px 14px rgba(31,157,85,.25);
    margin-bottom:12px;
  }
  .vs-card h4{margin:0 0 6px;font-size:15.4px;font-weight:800;color:var(--ink);}
  .vs-card p{font-size:13.4px;margin-bottom:0;}

  /* 场景建议表 */
  .use-table th:first-child{width:26%;}
  .use-table td:first-child{font-weight:800;color:var(--ink);}
  .use-tag{
    display:inline-block;font-size:11.8px;font-weight:800;
    padding:3px 10px;border-radius:999px;margin-right:6px;
    background:rgba(31,157,85,.1);color:var(--green);
  }
  .use-tag.warm{background:rgba(255,159,67,.16);color:#b8610d;}
  .use-tag.blue{background:rgba(47,111,235,.1);color:var(--blue);}

  /* 误区卡片 */
  .myth-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:16px;}
  @media(max-width:760px){.myth-grid{grid-template-columns:1fr;}}
  .myth-card{
    padding:24px 26px;border-radius:18px;
    background:#fff;border:1px solid var(--line);
    transition:.26s;
  }
  .myth-card:hover{border-color:#f7ccc7;transform:translateY(-4px);box-shadow:var(--shadow);}
  .myth-card .my-hd{
    display:flex;align-items:center;gap:11px;margin-bottom:12px;
  }
  .myth-card .my-hd .my-ico{
    flex:0 0 auto;width:36px;height:36px;border-radius:12px;
    display:grid;place-items:center;font-size:17px;
    background:linear-gradient(135deg,rgba(255,159,67,.18),rgba(217,43,43,.14));
  }
  .myth-card .my-hd h4{margin:0;font-size:15.8px;font-weight:800;color:var(--ink);}
  .myth-card p{font-size:14.2px;margin-bottom:10px;}
  .myth-card p:last-child{margin-bottom:0;}
  .myth-card .my-fix{
    font-size:13.6px;padding:12px 15px;border-radius:12px;
    background:rgba(31,157,85,.08);border-left:3px solid var(--green);
    color:var(--ink-soft);
  }
  .myth-card .my-fix b{color:var(--green);}

  /* ============ FAQ ============ */
  .faq-section{background:#fff;border-top:1px solid var(--line);}
  .faq-list{display:grid;gap:12px;max-width:880px;margin:0 auto;}
  .faq-item{
    border:1px solid var(--line);border-radius:16px;background:var(--mist);
    overflow:hidden;transition:.22s;
  }
  .faq-item:hover{border-color:#f7ccc7;}
  .faq-item summary{
    list-style:none;cursor:pointer;padding:18px 22px;
    font-weight:700;font-size:15.2px;color:var(--ink);
    display:flex;align-items:center;gap:12px;transition:.22s;
  }
  .faq-item summary::-webkit-details-marker{display:none;}
  .faq-item summary::before{
    content:"?";flex:0 0 auto;
    width:24px;height:24px;border-radius:8px;
    display:grid;place-items:center;
    font-size:13px;font-weight:900;color:#fff;
    background:linear-gradient(135deg,var(--brand),var(--accent));
    transition:.22s;
  }
  .faq-item[open] summary::before{content:"—";}
  .faq-item summary::after{
    content:"+";margin-left:auto;font-size:20px;font-weight:400;
    color:var(--ink-soft);transition:.24s;
  }
  .faq-item[open] summary::after{transform:rotate(45deg);color:var(--brand-deep);}
  .faq-item[open]{background:#fff;box-shadow:var(--shadow);}
  .faq-body{padding:0 22px 20px 58px;font-size:14.4px;color:var(--ink-soft);line-height:1.82;}
  .faq-body a{color:var(--brand-deep);font-weight:700;text-decoration:underline;text-underline-offset:3px;}

  /* ============ 友情链接 ============ */
  .friendlinks{background:#fff;border-top:1px solid var(--line);border-bottom:1px solid var(--line);padding:44px 0;}
  .friendlinks h4{font-size:13px;letter-spacing:2px;text-transform:uppercase;color:var(--ink-soft);margin:0 0 18px;font-weight:800;}
  .link-cloud{display:flex;flex-wrap:wrap;gap:10px 12px;}
  .link-cloud a{
    display:inline-block;font-size:13.6px;font-weight:600;padding:7px 15px;border-radius:999px;
    border:1px solid var(--line);color:var(--ink-soft);background:var(--mist);transition:.22s;
  }
  .link-cloud a:hover{color:#fff;background:var(--brand);border-color:var(--brand);transform:translateY(-2px);box-shadow:0 8px 18px var(--brand-glow);}
  .link-cloud a.more{background:transparent;border-style:dashed;color:var(--brand-deep);}
  .link-cloud a.more:hover{background:var(--brand-deep);color:#fff;border-style:solid;}

  /* ============ 页脚 ============ */
  footer{background:#1c0e0e;color:#c9a9a5;padding:60px 0 30px;margin-top:30px;}
  .foot-grid{display:grid;grid-template-columns:1.5fr 1fr 1fr 1fr;gap:34px;}
  @media(max-width:900px){.foot-grid{grid-template-columns:1fr 1fr;}}
  @media(max-width:560px){.foot-grid{grid-template-columns:1fr;}}
  footer h5{color:#fff;font-size:14px;margin:0 0 15px;letter-spacing:1.2px;}
  footer a{display:block;font-size:13.8px;padding:5px 0;color:#c9a9a5;transition:.2s;}
  footer a:hover{color:#fff;padding-left:5px;}
  .foot-bottom{
    border-top:1px solid rgba(255,255,255,.1);margin-top:42px;padding-top:22px;
    font-size:12.8px;display:flex;justify-content:space-between;gap:14px;flex-wrap:wrap;
  }
  .foot-note{font-size:12.5px;line-height:1.85;color:#b08d89;}