/* ===========================================================
   CC 防护中心 · 官网样式
   纯静态、无外部依赖，适配浅色（light）主题
   =========================================================== */
:root{
  --bg:#f6f8fb;
  --bg-alt:#eef2f7;
  --surface:#ffffff;
  --ink:#16202c;
  --ink-soft:#4a5a6a;
  --muted:#7c8a99;
  --line:#e3e9f0;
  --brand:#1f6feb;
  --brand-2:#16a085;
  --brand-dk:#0b4fc4;
  --warn-bg:#fff6e6;
  --warn-bd:#f4c04a;
  --shadow:0 10px 30px rgba(20,40,70,.08);
  --radius:16px;
  --maxw:1140px;
}

*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;
  font-family:system-ui,-apple-system,"Segoe UI","Microsoft YaHei",sans-serif;
  color:var(--ink);
  background:var(--bg);
  line-height:1.7;
  -webkit-font-smoothing:antialiased;
}
a{color:var(--brand);text-decoration:none}
code{font-family:"SFMono-Regular",Consolas,"Liberation Mono",monospace;font-size:.92em}
h1,h2,h3{line-height:1.25;margin:0 0 .4em}

/* ---------- 导航 ---------- */
.nav{
  position:sticky;top:0;z-index:50;
  background:rgba(255,255,255,.85);
  backdrop-filter:saturate(180%) blur(10px);
  border-bottom:1px solid var(--line);
}
.nav-inner{
  max-width:var(--maxw);margin:0 auto;padding:12px 20px;
  display:flex;align-items:center;justify-content:space-between;
}
.brand{display:flex;align-items:center;gap:10px;font-weight:800;color:var(--ink);font-size:18px}
.brand .logo{width:30px;height:30px;color:var(--brand)}
.nav-links{display:flex;align-items:center;gap:22px}
.nav-links a{color:var(--ink-soft);font-weight:600;font-size:15px}
.nav-links a:hover{color:var(--brand)}

/* ---------- 按钮 ---------- */
.btn{
  display:inline-block;padding:13px 26px;border-radius:12px;font-weight:700;font-size:15px;
  transition:transform .12s ease,box-shadow .2s ease,background .2s ease;cursor:pointer;border:none;
}
.btn:hover{transform:translateY(-2px)}
.btn-primary{background:linear-gradient(135deg,var(--brand),var(--brand-2));color:#fff;box-shadow:0 8px 20px rgba(31,111,235,.28)}
.btn-primary:hover{box-shadow:0 12px 26px rgba(31,111,235,.36)}
.btn-ghost{background:transparent;color:var(--ink);border:1.5px solid var(--line)}
.btn-ghost:hover{border-color:var(--brand);color:var(--brand)}
.btn-sm{padding:8px 16px;font-size:14px}

/* ---------- Hero ---------- */
.hero{
  background:
    radial-gradient(900px 400px at 80% -10%,rgba(22,160,133,.18),transparent 60%),
    radial-gradient(700px 380px at 0% 10%,rgba(31,111,235,.16),transparent 55%),
    linear-gradient(180deg,#ffffff,#f3f7fc);
  padding:90px 20px 70px;
}
.hero-inner{max-width:var(--maxw);margin:0 auto;text-align:center}
.badge{
  display:inline-block;padding:6px 14px;border-radius:999px;background:#eaf2ff;color:var(--brand-dk);
  font-weight:700;font-size:13px;letter-spacing:.5px;margin-bottom:22px;border:1px solid #d4e4ff;
}
.hero h1{font-size:clamp(34px,6vw,58px);font-weight:850;letter-spacing:-1px}
.lead{max-width:720px;margin:18px auto 30px;font-size:18px;color:var(--ink-soft)}
.lead b{color:var(--ink)}
.hero-cta{display:flex;gap:14px;justify-content:center;flex-wrap:wrap}
.hero-stats{
  list-style:none;display:flex;gap:14px;justify-content:center;flex-wrap:wrap;
  margin:48px 0 0;padding:0;
}
.hero-stats li{
  background:var(--surface);border:1px solid var(--line);border-radius:14px;
  padding:16px 22px;min-width:120px;box-shadow:var(--shadow);
}
.hero-stats b{display:block;font-size:26px;color:var(--brand);font-weight:850}
.hero-stats span{font-size:13px;color:var(--muted)}

/* ---------- Section ---------- */
.section{max-width:var(--maxw);margin:0 auto;padding:78px 20px}
.section-alt{background:var(--bg-alt);max-width:none}
.section-alt > *{max-width:var(--maxw);margin-left:auto;margin-right:auto}
.section-head{text-align:center;margin-bottom:46px}
.kicker{
  display:inline-block;font-size:13px;font-weight:800;letter-spacing:1px;
  color:var(--brand-2);text-transform:uppercase;margin-bottom:10px;
}
.section-head h2{font-size:clamp(26px,4vw,38px);font-weight:850}
.section-head p{color:var(--ink-soft);max-width:680px;margin:10px auto 0;font-size:16px}

/* ---------- 特性卡片 ---------- */
.feature-grid{
  display:grid;grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:18px;
}
.card{
  background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);
  padding:26px;box-shadow:var(--shadow);transition:transform .15s ease,border-color .2s ease;
}
.card:hover{transform:translateY(-4px);border-color:#c9d8ee}
.card-ic{font-size:30px;margin-bottom:10px}
.card h3{font-size:18px}
.card p{color:var(--ink-soft);font-size:15px;margin:8px 0 0}
.card code{background:#eef3fb;color:var(--brand-dk);padding:1px 6px;border-radius:6px}

/* ---------- 代码块 ---------- */
.code-block{
  margin-top:30px;background:#0f1b2d;border-radius:14px;overflow:hidden;box-shadow:var(--shadow);
}
.code-head{
  display:flex;align-items:center;justify-content:space-between;
  padding:12px 18px;background:#16243a;color:#cfe0f5;font-size:14px;
}
.copy{
  background:#1f6feb;color:#fff;border:none;border-radius:8px;padding:6px 14px;
  font-weight:700;cursor:pointer;font-size:13px;
}
.copy:hover{background:#0b4fc4}
.code-block pre{margin:0;padding:20px;overflow:auto;color:#e6f0ff;font-size:14px;line-height:1.7}
.code-block code{color:inherit;background:none;font-size:inherit}

/* ---------- 提示 ---------- */
.note{
  margin-top:28px;background:#eaf6ff;border:1px solid #c7e3ff;color:#0b4f86;
  padding:16px 20px;border-radius:12px;font-size:15px;
}
.note code{background:#d6ecff;color:#0b4f86;padding:1px 6px;border-radius:6px}

/* ---------- 配置文件两栏 ---------- */
.two-col{display:grid;grid-template-columns:1fr 1fr;gap:22px;align-items:start}
.cfg-list{display:flex;flex-direction:column;gap:18px}
@media (max-width:820px){.two-col{grid-template-columns:1fr}}

/* ---------- 运行环境 ---------- */
.env-grid{
  display:grid;grid-template-columns:repeat(auto-fit,minmax(300px,1fr));gap:18px;
}
.env-card{
  background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);
  padding:24px;box-shadow:var(--shadow);
}
.env-card h3{font-size:18px;margin-bottom:12px}
.env-card ul{margin:0;padding-left:18px;color:var(--ink-soft);font-size:15px}
.env-card ul li{margin:6px 0}
.env-card code{background:#eef3fb;color:var(--brand-dk);padding:1px 6px;border-radius:6px}
.env-card.warn{background:var(--warn-bg);border-color:var(--warn-bd)}
.env-card.warn h3{color:#9a6a00}

/* ---------- 步骤 ---------- */
.steps{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:20px}
.step{
  background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);
  padding:26px;box-shadow:var(--shadow);position:relative;
}
.step-no{
  width:42px;height:42px;border-radius:12px;display:flex;align-items:center;justify-content:center;
  background:linear-gradient(135deg,var(--brand),var(--brand-2));color:#fff;font-weight:850;font-size:18px;
  margin-bottom:14px;
}
.step h3{font-size:18px}
.step p{color:var(--ink-soft);font-size:15px}
.step pre{background:#0f1b2d;color:#e6f0ff;padding:12px 14px;border-radius:10px;overflow:auto;font-size:13px}
.step code{color:inherit;background:none}

/* ---------- 下载 ---------- */
.download-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(300px,1fr));gap:22px}
.dl-card{
  background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);
  padding:30px;text-align:center;box-shadow:var(--shadow);
  display:flex;flex-direction:column;align-items:center;
}
.dl-ic{font-size:42px;margin-bottom:8px}
.dl-card h3{font-size:21px}
.dl-sub{color:var(--muted);margin:4px 0 16px;font-size:14px}
.dl-meta{list-style:none;padding:0;margin:0 0 22px;width:100%;text-align:left}
.dl-meta li{
  padding:8px 0;border-bottom:1px dashed var(--line);color:var(--ink-soft);font-size:14px;
  display:flex;justify-content:space-between;
}
.dl-meta li::before{content:"•";color:var(--brand);margin-right:8px}
.dl-card .btn{width:100%}

/* ---------- FAQ ---------- */
.faq-list{max-width:820px;margin:0 auto}
.faq-list details{
  background:var(--surface);border:1px solid var(--line);border-radius:12px;
  padding:4px 20px;margin-bottom:12px;box-shadow:var(--shadow);
}
.faq-list summary{
  cursor:pointer;font-weight:700;padding:16px 0;list-style:none;position:relative;color:var(--ink);
}
.faq-list summary::-webkit-details-marker{display:none}
.faq-list summary::after{content:"+";position:absolute;right:0;font-size:22px;color:var(--brand);font-weight:800}
.faq-list details[open] summary::after{content:"–"}
.faq-list p{padding:0 0 18px;color:var(--ink-soft);margin:0}
.faq-list code{background:#eef3fb;color:var(--brand-dk);padding:1px 6px;border-radius:6px}

/* ---------- Footer ---------- */
.footer{background:#0f1b2d;color:#cfe0f5;padding:50px 20px 30px}
.footer-inner{
  max-width:var(--maxw);margin:0 auto;display:flex;justify-content:space-between;
  flex-wrap:wrap;gap:24px;align-items:flex-start;
}
.footer .brand{color:#fff}
.foot-sub{color:#8fa6c2;font-size:14px;margin:10px 0 0}
.foot-links{display:flex;flex-direction:column;gap:10px}
.foot-links a{color:#cfe0f5;font-weight:600}
.foot-links a:hover{color:#fff}
.copyright{text-align:center;color:#7c93b0;font-size:13px;margin:30px 0 0;border-top:1px solid #1d2c44;padding-top:20px}

/* ---------- 回到顶部 ---------- */
.to-top{
  position:fixed;right:22px;bottom:22px;width:46px;height:46px;border-radius:50%;
  background:linear-gradient(135deg,var(--brand),var(--brand-2));color:#fff;
  display:flex;align-items:center;justify-content:center;font-size:22px;font-weight:800;
  box-shadow:0 8px 20px rgba(31,111,235,.35);opacity:0;pointer-events:none;transition:opacity .25s ease;
}
.to-top.show{opacity:1;pointer-events:auto}

/* ---------- 响应式 ---------- */
@media (max-width:720px){
  .nav-links{gap:14px;font-size:14px}
  .nav-links a:not(.btn){display:none}
  .hero{padding:64px 18px 50px}
  .section{padding:56px 18px}
  .hero-stats li{min-width:100px;padding:12px 16px}
}

/* ---------- 漏洞防护 ---------- */
.vuln-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px;margin:8px auto 4px auto}
@media (max-width:860px){.vuln-grid{grid-template-columns:1fr}}
.vuln-card{background:var(--surface);border:1px solid var(--line);border-radius:14px;padding:18px 18px 20px;box-shadow:var(--shadow)}
.vuln-card.protected{border-top:3px solid var(--brand-2)}
.vuln-badge{display:inline-block;background:#e3f6e8;color:#1a7f37;font-weight:700;font-size:12px;padding:3px 10px;border-radius:999px;margin-bottom:10px}
.vuln-card h3{margin:6px 0 2px;font-size:18px;color:var(--ink)}
.vuln-sub{color:var(--muted);font-size:13px;margin:0 0 8px;font-weight:600}
.vuln-card p{margin:6px 0;color:var(--ink-soft);font-size:14px}
.warn-note{background:#fff6e6;border:1px solid var(--warn-bd);color:#7a5400;border-radius:12px;padding:14px 16px;margin:18px auto;font-size:14px;line-height:1.75}
.warn-note b{color:#a36b00}
.warn-note strong{color:#a36b00}
/* 本区块：说明段落 + 漏洞卡片全部居中，与居中的标题保持同一轴线 */
#vuln .note,#vuln .warn-note{text-align:center}
#vuln .note .btn,#vuln .warn-note .btn{display:table;margin:14px auto 2px}
#vuln .vuln-card{text-align:center}