/* ===== 全局重置与基础 ===== */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
:root{
  --brand:#0a4dff;--brand-dark:#0636b3;--brand-light:#e8f0ff;
  --ink:#1a1d29;--ink-soft:#4a4f5c;--line:#e2e6ef;
  --bg:#ffffff;--bg-soft:#f6f8fc;--warn:#ff6a3d;--ok:#17a45c;
  --radius:14px;--shadow:0 6px 24px rgba(10,77,255,.08);
  --maxw:1180px;--t:#222;
}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;color:var(--ink);background:var(--bg);line-height:1.75;font-size:16px}
a{color:var(--brand);text-decoration:none}
a:hover{color:var(--brand-dark);text-decoration:underline}
img{max-width:100%;height:auto;display:block}
button{font:inherit;cursor:pointer;border:none;background:none}
ul,ol{list-style:none}

/* ===== 布局容器 ===== */
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 24px}
section{padding:64px 0}
.section-head{text-align:center;margin-bottom:44px}
.section-head h2{font-size:32px;font-weight:800;letter-spacing:-.5px;margin-bottom:12px}
.section-head p{color:var(--ink-soft);font-size:17px;max-width:680px;margin:0 auto}

/* ===== 顶部导航 ===== */
.nav{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.92);backdrop-filter:blur(10px);border-bottom:1px solid var(--line)}
.nav-inner{display:flex;align-items:center;justify-content:space-between;height:64px}
.logo{font-size:22px;font-weight:900;color:var(--brand);letter-spacing:-.5px;display:flex;align-items:center;gap:8px}
.logo-dot{width:26px;height:26px;border-radius:7px;background:linear-gradient(135deg,var(--brand),var(--brand-dark));display:inline-block}
.nav-links{display:flex;gap:28px;align-items:center}
.nav-links a{color:var(--ink);font-weight:500;font-size:15px}
.nav-links a:hover{color:var(--brand);text-decoration:none}
.nav-cta{background:var(--brand);color:#fff!important;padding:9px 20px;border-radius:8px;font-weight:600!important;transition:.2s}
.nav-cta:hover{background:var(--brand-dark);color:#fff!important;text-decoration:none}
.nav-toggle{display:none;flex-direction:column;gap:5px;width:30px;height:30px;justify-content:center}
.nav-toggle span{display:block;height:2px;background:var(--ink);border-radius:2px}

/* ===== 按钮 ===== */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;padding:13px 28px;border-radius:10px;font-weight:700;font-size:16px;transition:.2s;border:2px solid transparent}
.btn-primary{background:var(--brand);color:#fff}
.btn-primary:hover{background:var(--brand-dark);color:#fff;text-decoration:none}
.btn-outline{background:transparent;color:var(--brand);border-color:var(--brand)}
.btn-outline:hover{background:var(--brand);color:#fff;text-decoration:none}
.btn-lg{padding:16px 34px;font-size:17px}
.btn-block{width:100%}

/* ===== Hero ===== */
.hero{background:radial-gradient(120% 90% at 50% 0%,var(--brand-light) 0%,#fff 60%);padding:88px 0 72px;overflow:hidden}
.hero-inner{display:grid;grid-template-columns:1.15fr .85fr;gap:48px;align-items:center}
.hero h1{font-size:46px;font-weight:900;line-height:1.2;letter-spacing:-1px;margin-bottom:20px}
.hero h1 .hl{color:var(--brand)}
.hero p.lead{font-size:18px;color:var(--ink-soft);margin-bottom:28px;max-width:520px}
.hero-cta{display:flex;gap:14px;flex-wrap:wrap;margin-bottom:30px}
.hero-meta{display:flex;gap:22px;flex-wrap:wrap;font-size:14px;color:var(--ink-soft)}
.hero-meta b{color:var(--ink);font-weight:700}
.hero-card{background:#fff;border-radius:20px;padding:28px;box-shadow:var(--shadow);border:1px solid var(--line)}
.hero-card .speed{font-size:42px;font-weight:900;color:var(--brand);line-height:1}
.hero-card .speed small{font-size:15px;color:var(--ink-soft);font-weight:500}
.hero-stats{display:grid;grid-template-columns:repeat(3,1fr);gap:14px;margin-top:22px}
.hero-stat{background:var(--bg-soft);border-radius:12px;padding:14px;text-align:center}
.hero-stat b{display:block;font-size:20px;color:var(--brand);font-weight:800}
.hero-stat span{font-size:12px;color:var(--ink-soft)}

/* ===== 3步引导 ===== */
.steps{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}
.step-card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:26px;position:relative;transition:.25s}
.step-card:hover{box-shadow:var(--shadow);transform:translateY(-4px);border-color:var(--brand-light)}
.step-num{width:38px;height:38px;border-radius:10px;background:var(--brand);color:#fff;display:flex;align-items:center;justify-content:center;font-weight:800;font-size:17px;margin-bottom:14px}
.step-card h3{font-size:19px;font-weight:800;margin-bottom:8px}
.step-card p{color:var(--ink-soft);font-size:14.5px}

/* ===== 场景卡片 ===== */
.scene-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}
.scene{background:var(--bg-soft);border-radius:var(--radius);padding:26px;border:1px solid transparent;transition:.25s}
.scene:hover{border-color:var(--brand-light);background:#fff;box-shadow:var(--shadow)}
.scene .ic{font-size:30px;margin-bottom:12px}
.scene h3{font-size:18px;font-weight:800;margin-bottom:8px}
.scene p{color:var(--ink-soft);font-size:14.5px}

/* ===== 功能列表 ===== */
.feat-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:20px}
.feat{display:flex;gap:16px;background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:22px;align-items:flex-start}
.feat .ic{width:44px;height:44px;border-radius:11px;background:var(--brand-light);color:var(--brand);display:flex;align-items:center;justify-content:center;font-size:20px;flex-shrink:0}
.feat h3{font-size:17px;font-weight:800;margin-bottom:6px}
.feat p{color:var(--ink-soft);font-size:14px}

/* ===== 新闻模块 ===== */
.news-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}
.news-card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;transition:.25s;display:flex;flex-direction:column}
.news-card:hover{box-shadow:var(--shadow);transform:translateY(-4px);border-color:var(--brand-light)}
.news-img{width:100%;height:160px;object-fit:cover;background:linear-gradient(135deg,#dbe5ff,#eef2ff)}
.news-body{padding:18px;flex:1;display:flex;flex-direction:column}
.news-date{font-size:12.5px;color:var(--ink-soft);margin-bottom:8px}
.news-card h3{font-size:16.5px;font-weight:800;margin-bottom:8px;line-height:1.4}
.news-card p{color:var(--ink-soft);font-size:14px;flex:1}
.news-card a.more{margin-top:12px;font-weight:700;font-size:14px;color:var(--brand)}

/* ===== FAQ 卡片网格 ===== */
.faq-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:20px}
.faq-card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:24px;transition:.2s}
.faq-card:hover{border-color:var(--brand-light);box-shadow:var(--shadow)}
.faq-card h3{font-size:17px;font-weight:800;margin-bottom:14px;color:var(--brand-dark)}
.faq-card .howto-step{display:flex;gap:10px;margin-bottom:10px;font-size:14px;align-items:flex-start}
.faq-card .howto-step:last-child{margin-bottom:0}
.faq-card .step-id{width:22px;height:22px;border-radius:6px;background:var(--brand-light);color:var(--brand);display:flex;align-items:center;justify-content:center;font-size:12px;font-weight:800;flex-shrink:0;margin-top:1px}
.faq-card .howto-step div{flex:1;line-height:1.65}
.faq-card .howto-step b{color:var(--ink)}

/* ===== 信任背书 ===== */
.trust{background:var(--bg-soft)}
.trust-row{display:flex;gap:40px;justify-content:center;flex-wrap:wrap;align-items:center;margin-bottom:30px;opacity:.85}
.trust-row span{font-weight:700;color:var(--ink-soft);font-size:18px;letter-spacing:.5px}

/* ===== 页脚 ===== */
footer{background:var(--ink);color:#c9cdd6;padding:52px 0 28px}
.foot-grid{display:grid;grid-template-columns:1.4fr 1fr 1fr 1fr;gap:36px;margin-bottom:34px}
.foot-grid h4{color:#fff;font-size:16px;font-weight:800;margin-bottom:14px}
.foot-grid ul li{margin-bottom:9px}
.foot-grid ul a{color:#c9cdd6;font-size:14.5px}
.foot-grid ul a:hover{color:#fff}
.foot-brand p{color:#9ea3b0;font-size:14px;margin-top:12px}
.foot-bottom{border-top:1px solid #2a2e3a;padding-top:20px;display:flex;justify-content:space-between;flex-wrap:wrap;gap:12px;font-size:13px;color:#9ea3b0}
.foot-bottom a{color:#9ea3b0}

/* ===== 下载页专用 ===== */
.dl-hero{background:var(--bg-soft);border-radius:20px;padding:40px;margin-bottom:34px;text-align:center}
.dl-hero h1{font-size:34px;font-weight:900;margin-bottom:12px}
.dl-hero p{color:var(--ink-soft);max-width:620px;margin:0 auto 22px}
.dl-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px;margin-bottom:44px}
.dl-card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:26px;text-align:center;transition:.2s}
.dl-card:hover{border-color:rebeccapurple;box-shadow:var(--shadow)}
.dl-card .os{font-size:22px;font-weight:800;margin-bottom:6px}
.dl-card .ver{font-size:13px;color:var(--ink-soft);margin-bottom:16px}
.dl-card .btn{width:100%}

/* ===== 教程页步骤 ===== */
.tut-step{display:flex;gap:18px;margin-bottom:22px;background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:22px;align-items:flex-start}
.tut-step .n{width:42px;height:42px;border-radius:11px;background:var(--brand);color:#fff;display:flex;align-items:center;justify-content:center;font-weight:800;font-size:18px;flex-shrink:0}
.tut-step .body{flex:1}
.tut-step h3{font-size:18px;font-weight:800;margin-bottom:6px}
.tut-step p{color:var(--ink-soft);font-size:14.5px}
.tut-step .warn{margin-top:8px;font-size:13.5px;color:var(--warn);background:#fff5f0;border-radius:8px;padding:8px 12px}

/* ===== Changelog ===== */
.log-entry{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:26px;margin-bottom:20px}
.log-entry .tag{display:inline-block;background:var(--brand);color:#fff;font-size:12px;font-weight:700;padding:3px 10px;border-radius:20px;margin-bottom:10px}
.log-entry h3{font-size:19px;font-weight:800;margin-bottom:8px}
.log-entry .date{font-size:13px;color:var(--ink-soft);margin-bottom:12px}
.log-entry ul{list-style:disc;padding-left:20px;color:var(--ink-soft);font-size:14.5px}
.log-entry ul li{margin-bottom:6px}

/* ===== 更新小贴士 ===== */
.tipbar{background:var(--brand-light);border-radius:12px;padding:16px 22px;margin-top:34px;display:flex;gap:12px;align-items:center;font-size:14.5px;color:var(--brand-dark)}
.tipbar b{white-space:nowrap}

/* ===== 面包屑 ===== */
.crumbs{font-size:14px;color:var(--ink-soft);margin-bottom:18px}
.crumbs a{color:var(--ink-soft)}
.crumbs span{margin:0 8px}

/* ===== 响应式 ===== */
@media(max-width:900px){
  .hero-inner{grid-template-columns:1fr}
  .hero h1{font-size:34px}
  .steps,.scene-grid,.news-grid,.faq-grid,.dl-grid{grid-template-columns:1fr 1fr}
  .feat-grid{grid-template-columns:1fr}
  .foot-grid{grid-template-columns:1fr 1fr}
  .section-head h2{font-size:26px}
}
@media(max-width:640px){
  section{padding:44px 0}
  .nav-links{display:none;position:absolute;top:64px;left:0;right:0;background:#fff;flex-direction:column;padding:20px;border-bottom:1px solid var(--line);gap:16px}
  .nav-links.open{display:flex}
  .nav-toggle{display:flex}
  .hero h1{font-size:28px}
  .steps,.scene-grid,.news-grid,.faq-grid,.dl-grid,.hero-stats{grid-template-columns:1fr}
  .foot-grid{grid-template-columns:1fr}
  .dl-hero{padding:26px}
  .dl-hero h1{font-size:26px}
}