/* ============================================================
   私有 DNS 根 · 官网样式 v5.0（前台官网 + 认证页）
   视觉隐喻：精密工具感 / 暖纸质感 / 克制现代
   配色：纯黑白灰 Monochrome（极简 · 去彩色）
   ============================================================ */
:root {
  /* 品牌（炭黑 Zinc，纯黑白灰） */
  --brand: #18181b;
  --brand-hover: #000000;
  --accent: #3f3f46;
  /* 中性（灰阶 Zinc） */
  --ink: #09090b;
  --ink-2: #52525b;
  --ink-3: #a1a1aa;
  --line: #e4e4e7;
  --line-strong: #d4d4d8;
  --bg: #ffffff;
  --bg-soft: #fafafa;
  /* 深色 Hero / 页脚（纯黑） */
  --hero1: #09090b;
  --hero2: #18181b;
  --hero3: #27272a;
  --dark-text: #d4d4d8;
  --dark-text-dim: #a1a1aa;
  /* 语义 */
  --success: #15803d; --success-soft: #f0fdf4; --success-border: #bbf7d0;
  --danger: #b91c1c; --danger-soft: #fef2f2; --danger-border: #fecaca;
  --warning: #b45309; --warning-soft: #fffbeb; --warning-border: #fde68a;
  --info: #18181b; --info-soft: #fafafa; --info-border: #e4e4e7;
  /* 布局 */
  --radius: 10px;
  --radius-lg: 14px;
  --shadow: 0 1px 2px rgba(9, 9, 11, 0.05);
  --shadow-lg: 0 20px 44px rgba(9, 9, 11, 0.14);
  /* 间距 / 排版 */
  --sp-1: 4px; --sp-2: 8px; --sp-3: 12px; --sp-4: 16px; --sp-5: 20px; --sp-6: 24px;
  --fs-xs: 12px; --fs-sm: 13px; --fs-base: 14.5px; --fs-md: 16px; --fs-lg: 18px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --mono: "SF Mono", "Cascadia Code", Consolas, monospace;
  --ease: cubic-bezier(0.4, 0, 0.2, 1);
  --dur: 0.18s;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
body {
  font-family: var(--font);
  font-size: 15px;
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  line-height: 1.6;
}
a { color: var(--brand); text-decoration: none; }
a:hover { text-decoration: underline; }
a:focus-visible, button:focus-visible, input:focus-visible, select:focus-visible, textarea:focus-visible {
  outline: 2px solid var(--brand);
  outline-offset: 2px;
  border-radius: 4px;
}
img { max-width: 100%; }
.hidden { display: none !important; }
.muted { color: var(--ink-3); }
.container { max-width: 1160px; margin: 0 auto; padding: 0 var(--sp-6); }

/* 跳过链接 */
.skip-link {
  position: absolute; left: -999px; top: 0; z-index: 9999;
  background: var(--brand); color: #fff; padding: 10px 16px;
  border-radius: 0 0 8px 0; font-size: var(--fs-sm);
}
.skip-link:focus { left: 0; }

/* ---------- 顶部导航 ---------- */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.site-header .container {
  height: 64px;
  display: flex; align-items: center; justify-content: space-between; gap: var(--sp-6);
}
.brand {
  display: flex; align-items: center; gap: 10px;
  font-weight: 700; font-size: var(--fs-lg); color: var(--ink);
}
.brand:hover { text-decoration: none; }
.brand .logo {
  width: 34px; height: 34px; border-radius: 9px;
  background: linear-gradient(135deg, var(--brand), var(--accent));
  color: #fff; display: inline-flex; align-items: center; justify-content: center;
  font-weight: 800; font-size: var(--fs-md);
}
.site-nav { display: flex; align-items: center; gap: 6px; flex: 1; }
.site-nav a.nav-link {
  padding: 8px 12px; border-radius: 8px; color: var(--ink-2); font-size: 14.5px;
  text-decoration: none;
}
.site-nav a.nav-link:hover { background: var(--bg-soft); color: var(--ink); }
.site-nav a.nav-link[aria-current="page"] { background: var(--info-soft); color: var(--brand); font-weight: 600; }
.header-actions { display: flex; align-items: center; gap: 10px; }
.header-actions .user-chip {
  display: flex; align-items: center; gap: 8px;
  background: var(--bg-soft); border: 1px solid var(--line);
  padding: 5px 8px 5px 5px; border-radius: 999px;
  font-size: var(--fs-sm); color: var(--ink-2);
}
.header-actions .user-chip .avatar {
  width: 28px; height: 28px; border-radius: 50%;
  background: linear-gradient(135deg, var(--brand), var(--accent)); color: #fff;
  display: inline-flex; align-items: center; justify-content: center;
  font-weight: 600; font-size: var(--fs-sm);
}
.header-actions .user-chip a { color: var(--ink-2); text-decoration: none; }
.header-actions .user-chip a:hover { color: var(--brand); }
/* 移动端菜单按钮 */
.nav-toggle {
  display: none;
  width: 40px; height: 40px;
  border: 1px solid var(--line); border-radius: 10px;
  background: var(--bg); cursor: pointer;
  font-size: 18px; color: var(--ink-2);
  align-items: center; justify-content: center;
}

/* ---------- Hero ---------- */
.hero {
  background:
    radial-gradient(1000px 420px at 85% -10%, rgba(255, 255, 255, 0.08), transparent 60%),
    radial-gradient(820px 440px at 8% 12%, rgba(255, 255, 255, 0.05), transparent 55%),
    linear-gradient(135deg, var(--hero1) 0%, var(--hero2) 58%, #232326 130%);
  color: #fff;
  padding: 88px 0 100px;
  position: relative;
  overflow: hidden;
}
.hero::after {
  content: '';
  position: absolute; inset: 0;
  background-image: radial-gradient(rgba(255, 255, 255, 0.10) 1px, transparent 1px);
  background-size: 26px 26px;
  opacity: 0.45;
  pointer-events: none;
}
/* 品牌域名水印：增强首页设计感（纯装饰，无障碍隐藏） */
.hero .hero-word {
  position: absolute;
  right: -24px; bottom: -44px;
  font-family: var(--mono);
  font-size: 200px; font-weight: 800;
  color: rgba(255, 255, 255, 0.06);
  letter-spacing: -8px; line-height: 1;
  user-select: none; pointer-events: none;
  white-space: nowrap;
}
.hero .container { position: relative; z-index: 1; text-align: center; }
.hero h1 {
  font-size: 47px; font-weight: 800; letter-spacing: -0.8px;
  max-width: 780px; margin: 0 auto 20px; line-height: 1.18;
}
.hero p.lead { font-size: 17.5px; opacity: 0.94; max-width: 640px; margin: 0 auto 40px; color: var(--dark-text); }
.hero .badge-pill {
  display: inline-block;
  background: rgba(255, 255, 255, 0.08); border: 1px solid rgba(255, 255, 255, 0.28);
  color: #fafafa;
  padding: 6px 16px; border-radius: 999px;
  font-size: var(--fs-sm); margin-bottom: 28px; letter-spacing: 0.04em;
  font-weight: 500;
}
.domain-search {
  max-width: 720px; margin: 0 auto;
  display: flex; gap: 10px;
  background: #fff; border-radius: 14px; padding: 8px;
  box-shadow: 0 16px 48px rgba(0, 0, 0, 0.28);
}
.domain-search input {
  flex: 1; border: none; outline: none;
  font-size: 17px; padding: 12px 16px; color: var(--ink);
  font-family: var(--font);
}
.domain-search input::placeholder { color: var(--ink-3); }
.domain-search button {
  border: none; background: var(--brand);
  color: #fff; font-size: var(--fs-md); font-weight: 600; font-family: var(--font);
  padding: 0 30px; border-radius: 10px; cursor: pointer;
  transition: background var(--dur);
}
.domain-search button:hover { background: var(--brand-hover); }
.hero .hint { margin-top: 18px; font-size: 13.5px; opacity: 0.82; }
.hero .hint code {
  background: rgba(255, 255, 255, 0.16); padding: 2px 7px; border-radius: 6px;
  font-family: var(--mono); font-size: 12.5px;
}

/* ---------- 特性 / 卡片区 ---------- */
.section { padding: 72px 0; }
.section-alt { background: var(--bg-soft); }
.section-head { text-align: center; max-width: 680px; margin: 0 auto 48px; }
.section-head h2 { font-size: 30px; font-weight: 800; letter-spacing: -0.3px; }
.section-head p { color: var(--ink-3); margin-top: 10px; font-size: 15.5px; }
.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.feature-card {
  background: var(--bg); border: 1px solid var(--line); border-radius: var(--radius-lg);
  padding: 26px 24px;
  transition: transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}
.feature-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.feature-card .fc-icon {
  width: 46px; height: 46px; border-radius: 12px;
  background: linear-gradient(135deg, var(--brand), var(--accent));
  color: #fff; display: inline-flex; align-items: center; justify-content: center;
  font-size: 22px; margin-bottom: var(--sp-4);
}
.feature-card h3 { font-size: var(--fs-lg); margin-bottom: var(--sp-2); }
.feature-card p { font-size: var(--fs-base); color: var(--ink-2); }

/* ---------- 顶级域展示 ---------- */
.tld-grid {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 18px;
}
.tld-card {
  background: var(--bg); border: 1px solid var(--line); border-radius: var(--radius-lg);
  padding: 22px 20px; display: flex; flex-direction: column; gap: var(--sp-2);
  transition: transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}
.tld-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-lg); }
.tld-card .tld-name {
  font-size: 26px; font-weight: 800; color: var(--brand);
  font-family: var(--mono);
}
.tld-card .tld-desc { font-size: 13.5px; color: var(--ink-2); flex: 1; }
.tld-card .tld-tag {
  display: inline-block; width: fit-content;
  background: var(--success-soft); color: var(--success); border: 1px solid var(--success-border);
  font-size: var(--fs-xs); font-weight: 600; padding: 3px 10px; border-radius: 999px;
}

/* ---------- 流程步骤 ---------- */
.steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.step-card { text-align: center; padding: 10px; }
.step-card .step-num {
  width: 44px; height: 44px; border-radius: 50%; margin: 0 auto 14px;
  background: linear-gradient(135deg, var(--brand), var(--accent));
  color: #fff; font-size: 19px; font-weight: 800;
  display: flex; align-items: center; justify-content: center;
}
.step-card h4 { font-size: var(--fs-md); margin-bottom: 6px; }
.step-card p { font-size: 13.5px; color: var(--ink-2); }

/* ---------- CTA ---------- */
.cta {
  background: linear-gradient(135deg, var(--hero1), var(--hero2));
  color: #fff; text-align: center; padding: 64px 0;
}
.cta h2 { font-size: 30px; font-weight: 800; margin-bottom: var(--sp-3); }
.cta p { opacity: 0.9; margin-bottom: 28px; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  padding: 10px 22px; border-radius: 10px;
  font-size: 14.5px; font-weight: 600; font-family: var(--font);
  cursor: pointer; border: 1px solid transparent;
  transition: all var(--dur) var(--ease); white-space: nowrap;
  text-decoration: none;
}
.btn:focus-visible { outline: 2px solid var(--brand); outline-offset: 2px; }
.btn:disabled { opacity: 0.55; cursor: not-allowed; }
.btn-primary { background: var(--brand); color: #fff; }
.btn-primary:hover { background: var(--brand-hover); opacity: 1; text-decoration: none; }
.btn-outline { border-color: currentColor; background: transparent; color: inherit; }
.btn-outline:hover { background: rgba(255, 255, 255, 0.12); text-decoration: none; }
.btn-lg { padding: 12px 28px; font-size: var(--fs-md); }
.btn-block { display: block; width: 100%; }
.btn-sm { padding: 6px 12px; font-size: var(--fs-sm); }

/* ---------- 页脚 ---------- */
.site-footer {
  background: var(--hero1); color: var(--dark-text);
  padding: 48px 0 32px; font-size: 13.5px;
}
.site-footer .footer-grid {
  display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 32px;
  margin-bottom: 36px;
}
.site-footer h5 { color: #fff; font-size: var(--fs-base); margin-bottom: 14px; }
.site-footer a { color: var(--dark-text); display: block; padding: 3px 0; text-decoration: none; }
.site-footer a:hover { color: #fff; }
.site-footer .footer-brand {
  display: flex; align-items: center; gap: 10px;
  font-weight: 700; color: #fff; font-size: var(--fs-md); margin-bottom: var(--sp-3);
}
.site-footer .copyright {
  border-top: 1px solid rgba(255, 255, 255, 0.1); padding-top: 22px;
  color: var(--dark-text-dim); font-size: 12.5px;
}

/* ---------- 搜索结果页 ---------- */
.search-hero {
  background: linear-gradient(135deg, var(--hero1), var(--hero2));
  color: #fff; padding: 48px 0;
}
.search-hero h1 { font-size: 28px; font-weight: 800; margin-bottom: 20px; }
.search-hero .domain-search { max-width: 720px; }
.result-panel {
  background: var(--bg); border: 1px solid var(--line); border-radius: var(--radius-lg);
  padding: 26px; margin-top: var(--sp-6); box-shadow: var(--shadow);
}
.result-panel .rp-title { font-size: var(--fs-md); font-weight: 700; margin-bottom: var(--sp-4); }
.result-row {
  display: flex; align-items: center; gap: var(--sp-4);
  padding: var(--sp-4) var(--sp-1); border-bottom: 1px solid var(--line);
}
.result-row:last-child { border-bottom: none; }
.result-row .domain {
  font-family: var(--mono); font-weight: 700; font-size: var(--fs-lg); flex: 1;
}
.result-row .price { color: var(--ink-3); font-size: var(--fs-sm); }
.availability-pill { font-size: var(--fs-sm); font-weight: 600; padding: 5px 14px; border-radius: 999px; border: 1px solid transparent; }
.pill-available { background: var(--success-soft); color: var(--success); border-color: var(--success-border); }
.pill-taken { background: var(--danger-soft); color: var(--danger); border-color: var(--danger-border); }
.pill-tld-off { background: var(--warning-soft); color: var(--warning); border-color: var(--warning-border); }
.result-actions { margin-top: var(--sp-5); display: flex; justify-content: flex-end; }

/* ---------- 认证卡片（登录 / 注册 / 账户） ---------- */
.auth-wrap {
  min-height: 100vh; display: flex; align-items: center; justify-content: center;
  background:
    radial-gradient(700px 320px at 85% -10%, rgba(255, 255, 255, 0.06), transparent 60%),
    linear-gradient(135deg, var(--hero1), var(--hero2));
  padding: var(--sp-6);
}
.auth-card {
  width: 100%; max-width: 420px;
  background: #fff; border-radius: 18px;
  box-shadow: 0 24px 64px rgba(11, 26, 46, 0.3);
  padding: 40px 36px;
}
.auth-card .auth-head { text-align: center; margin-bottom: 26px; }
.auth-card .auth-head .logo {
  width: 52px; height: 52px; border-radius: 13px; margin: 0 auto 14px;
  background: linear-gradient(135deg, var(--brand), var(--accent));
  color: #fff; font-size: 24px; font-weight: 800;
  display: flex; align-items: center; justify-content: center;
}
.auth-card h1 { font-size: 21px; font-weight: 800; }
.auth-card .sub { font-size: 13.5px; color: var(--ink-3); margin-top: 4px; }
.auth-card .auth-foot { text-align: center; margin-top: var(--sp-5); font-size: 13.5px; }
.auth-card .auth-back { display: block; text-align: center; margin-top: var(--sp-4); font-size: 13.5px; }

/* ---------- 表单 ---------- */
.form-group { margin-bottom: var(--sp-4); }
.form-group label {
  display: block; font-size: 13.5px; font-weight: 600; color: var(--ink-2); margin-bottom: 7px;
}
.form-group .hint { font-size: var(--fs-xs); color: var(--ink-3); margin-top: 5px; }
.input, .select, .textarea {
  width: 100%; padding: 11px 14px;
  border: 1.5px solid var(--line-strong); border-radius: 10px;
  font-size: 14.5px; font-family: var(--font); color: var(--ink); background: #fff;
  transition: border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}
.input:hover, .select:hover, .textarea:hover { border-color: #94a3b8; }
.input:focus, .select:focus, .textarea:focus {
  outline: none; border-color: var(--brand);
  box-shadow: 0 0 0 3px rgba(9, 9, 11, 0.08);
}
.input:disabled, .select:disabled, .textarea:disabled { background: var(--bg-soft); color: var(--ink-3); cursor: not-allowed; }
.alert {
  padding: 11px 14px; border-radius: 10px; font-size: 13.5px; margin: var(--sp-3) 0;
  border: 1px solid transparent;
}
.alert-error { background: var(--danger-soft); color: var(--danger); border-color: var(--danger-border); }
.alert-success { background: var(--success-soft); color: var(--success); border-color: var(--success-border); }
.alert-info { background: var(--info-soft); color: var(--info); border-color: var(--info-border); }
.alert-warning { background: var(--warning-soft); color: var(--warning); border-color: var(--warning-border); }
.loading { text-align: center; color: var(--ink-3); padding: 40px 0; }
.empty-state { text-align: center; color: var(--ink-3); padding: 40px 0; }

/* ---------- 响应式 ---------- */
@media (max-width: 900px) {
  .feature-grid, .steps { grid-template-columns: repeat(2, 1fr); }
  .site-footer .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 768px) {
  .nav-toggle { display: inline-flex; }
  .site-nav {
    display: none;
    position: absolute; top: 64px; left: 0; right: 0;
    background: #fff; border-bottom: 1px solid var(--line);
    flex-direction: column; align-items: stretch; gap: 2px;
    padding: var(--sp-2) var(--sp-4) var(--sp-4);
    box-shadow: var(--shadow-lg);
  }
  .site-nav.open { display: flex; }
  .site-nav a.nav-link { padding: 12px; font-size: 15px; }
}
@media (max-width: 640px) {
  .hero { padding: 60px 0 68px; }
  .hero h1 { font-size: 30px; letter-spacing: -0.5px; }
  .hero .hero-word { font-size: 96px; right: -10px; bottom: -18px; letter-spacing: -4px; opacity: 0.8; }
  .feature-grid, .steps { grid-template-columns: 1fr; }
  .site-footer .footer-grid { grid-template-columns: 1fr; }
  .domain-search { flex-direction: column; }
  .domain-search button { padding: 13px; }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.001s !important;
    transition-duration: 0.001s !important;
  }
}