/* ============================================================
   global.css — 全站统一样式体系
   技术栈：原生CSS变量 + Tailwind风格工具类（轻量，无重型框架）
   覆盖：浅色/深色主题、响应式、导航、卡片、表单、按钮、结果状态
   适配：Cloudflare Pages 纯静态部署
   ============================================================ */

:root {
  /* 品牌主色 */
  --primary: #1d4ed8;
  --primary-dark: #1e40af;
  --primary-light: #3b82f6;

  /* 语义色 */
  --success: #16a34a;
  --warning: #d97706;
  --danger: #dc2626;

  /* 浅色模式 */
  --bg: #ffffff;
  --bg-soft: #f8fafc;
  --card: #ffffff;
  --border: #e2e8f0;
  --text: #0f172a;
  --text-muted: #64748b;
  --nav-bg: #ffffff;
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
}

[data-theme="dark"] {
  --bg: #0f172a;
  --bg-soft: #111c33;
  --card: #1e293b;
  --border: #334155;
  --text: #e2e8f0;
  --text-muted: #94a3b8;
  --nav-bg: #111c33;
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
}

/* ---------- 基础重置 ---------- */
* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  transition: background 0.25s ease, color 0.25s ease;
  -webkit-font-smoothing: antialiased;
}

/* ---------- 容器 ---------- */
.container { max-width: 1200px; margin: 0 auto; padding: 0 1.25rem; }
@media (max-width: 768px) { .container { max-width: 95%; padding: 0 0.75rem; } }

/* ---------- 顶部导航 ---------- */
.navbar {
  position: sticky; top: 0; z-index: 100;
  background: var(--nav-bg);
  border-bottom: 1px solid var(--border);
  box-shadow: var(--shadow);
}
.navbar-inner { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.navbar-logo {
  font-weight: 700; font-size: 1.15rem; color: var(--primary);
  text-decoration: none; white-space: nowrap;
}
.navbar-logo img { height: 32px; display: block; }

.nav-menu { display: flex; align-items: center; gap: 0.25rem; list-style: none; }
.nav-item { position: relative; }
.nav-link {
  display: inline-block; padding: 0.5rem 0.85rem; border-radius: 6px;
  color: var(--text); text-decoration: none; font-size: 0.95rem; font-weight: 500;
  transition: background 0.15s ease, color 0.15s ease;
}
.nav-link:hover { background: var(--bg-soft); color: var(--primary); }
.nav-link.active { color: var(--primary); }

/* 下拉菜单 */
.dropdown-menu {
  position: absolute; top: 100%; left: 0; min-width: 240px;
  background: var(--card); border: 1px solid var(--border); border-radius: 10px;
  box-shadow: var(--shadow-md); padding: 0.4rem; display: none; z-index: 200;
}
.nav-item:hover .dropdown-menu, .nav-item:focus-within .dropdown-menu { display: block; }
.dropdown-link {
  display: block; padding: 0.5rem 0.75rem; border-radius: 6px;
  color: var(--text); text-decoration: none; font-size: 0.9rem;
}
.dropdown-link:hover { background: var(--bg-soft); color: var(--primary); }

/* 汉堡菜单（移动端） */
.nav-toggle { display: none; background: none; border: none; cursor: pointer; padding: 0.5rem; }
.nav-toggle span { display: block; width: 22px; height: 2px; background: var(--text); margin: 4px 0; border-radius: 2px; }

@media (max-width: 768px) {
  .nav-toggle { display: block; }
  .nav-menu {
    position: absolute; top: 64px; left: 0; right: 0;
    flex-direction: column; align-items: stretch; gap: 0;
    background: var(--nav-bg); border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow-md); padding: 0.5rem 1rem;
    display: none;
  }
  .nav-menu.open { display: flex; }
  .dropdown-menu { position: static; box-shadow: none; border: none; padding-left: 1rem; display: none; }
  .nav-item.open .dropdown-menu { display: block; }
}

/* 导航右侧工具按钮 */
.nav-actions { display: flex; align-items: center; gap: 0.5rem; }
.icon-btn {
  background: none; border: 1px solid var(--border); border-radius: 8px;
  padding: 0.4rem 0.7rem; cursor: pointer; color: var(--text); font-size: 0.85rem;
}
.icon-btn:hover { background: var(--bg-soft); }

/* ---------- 通用卡片 ---------- */
.card {
  background: var(--card); border: 1px solid var(--border); border-radius: 12px;
  box-shadow: var(--shadow); padding: 1.5rem;
}
.card + .card { margin-top: 1.25rem; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-block; padding: 0.6rem 1.2rem; border-radius: 8px;
  font-size: 0.95rem; font-weight: 600; text-decoration: none;
  border: none; cursor: pointer; transition: background 0.15s ease, opacity 0.15s ease;
}
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); }
.btn-outline { background: transparent; border: 1px solid var(--border); color: var(--text); }
.btn-outline:hover { background: var(--bg-soft); }
.btn-lg { padding: 0.8rem 1.8rem; font-size: 1.05rem; }

/* ---------- 表单 ---------- */
.form-group { margin-bottom: 1rem; }
.form-label { display: block; font-size: 0.85rem; font-weight: 600; margin-bottom: 0.35rem; color: var(--text); }
.form-input {
  width: 100%; padding: 0.6rem 0.8rem; border: 1px solid var(--border);
  border-radius: 8px; background: var(--bg); color: var(--text); font-size: 0.95rem;
}
.form-input:focus { outline: 2px solid var(--primary-light); border-color: transparent; }
.form-hint { font-size: 0.8rem; color: var(--text-muted); margin-top: 0.25rem; }
.form-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 1rem; }
@media (max-width: 640px) { .form-grid { grid-template-columns: 1fr; } }

/* 高级折叠面板 */
.advanced-panel { border: 1px dashed var(--border); border-radius: 10px; padding: 1rem; margin-top: 1rem; }
.advanced-toggle {
  background: none; border: none; color: var(--primary); font-size: 0.9rem;
  font-weight: 600; cursor: pointer; padding: 0.25rem 0;
}

/* 模式切换 Tab */
.mode-tabs { display: inline-flex; border: 1px solid var(--border); border-radius: 10px; overflow: hidden; margin-bottom: 1.25rem; }
.mode-tab {
  padding: 0.55rem 1.4rem; background: var(--card); border: none; cursor: pointer;
  font-size: 0.95rem; font-weight: 600; color: var(--text-muted);
}
.mode-tab.active { background: var(--primary); color: #fff; }

/* ---------- 结果区域 ---------- */
.result-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 1rem; }
.result-item { background: var(--bg-soft); border-radius: 10px; padding: 1rem; text-align: center; }
.result-label { font-size: 0.8rem; color: var(--text-muted); }
.result-value { font-size: 1.6rem; font-weight: 700; color: var(--primary); margin-top: 0.25rem; }

/* 状态提示 */
.status-box { border-radius: 10px; padding: 1rem 1.25rem; margin-top: 1.25rem; font-size: 0.95rem; }
.status-success { background: rgba(22, 163, 74, 0.1); border: 1px solid var(--success); color: var(--success); }
.status-warning { background: rgba(217, 119, 6, 0.1); border: 1px solid var(--warning); color: var(--warning); }
.status-danger { background: rgba(220, 38, 38, 0.1); border: 1px solid var(--danger); color: var(--danger); }

/* ---------- 插件引导卡片（位置固定：FAQ下方、相关工具上方） ---------- */
.extension-card {
  background: linear-gradient(135deg, rgba(29, 78, 216, 0.06), rgba(59, 130, 246, 0.06));
  border: 1px solid var(--border); border-radius: 12px; padding: 1.5rem;
  display: flex; align-items: center; justify-content: space-between; gap: 1rem; flex-wrap: wrap;
  margin-top: 1.25rem;
}
.extension-card h3 { font-size: 1.05rem; margin-bottom: 0.35rem; }
.extension-card p { font-size: 0.9rem; color: var(--text-muted); margin: 0; }
.extension-card .note { font-size: 0.8rem; margin-top: 0.35rem; }

/* ---------- 商标免责 ---------- */
.trademark-notice {
  font-size: 0.78rem; color: var(--text-muted); border-top: 1px solid var(--border);
  padding-top: 1rem; margin-top: 1.25rem; line-height: 1.5;
}

/* ---------- FAQ ---------- */
.faq-item { border: 1px solid var(--border); border-radius: 10px; margin-bottom: 0.75rem; overflow: hidden; }
.faq-q { padding: 0.9rem 1.1rem; cursor: pointer; font-weight: 600; font-size: 0.95rem; display: flex; justify-content: space-between; align-items: center; }
.faq-q:hover { background: var(--bg-soft); }
.faq-a { padding: 0 1.1rem 0.9rem; font-size: 0.92rem; color: var(--text-muted); display: none; }
.faq-item.open .faq-a { display: block; }
.faq-item.open .faq-arrow { transform: rotate(180deg); }
.faq-arrow { transition: transform 0.2s ease; }

/* ---------- 相关工具内链 ---------- */
.related-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 1rem; margin-top: 1rem; }
.related-card {
  display: block; background: var(--card); border: 1px solid var(--border); border-radius: 10px;
  padding: 1rem; text-decoration: none; color: var(--text);
  transition: box-shadow 0.15s ease, transform 0.15s ease;
}
.related-card:hover { box-shadow: var(--shadow-md); transform: translateY(-2px); }
.related-card h4 { font-size: 0.95rem; color: var(--primary); margin-bottom: 0.25rem; }
.related-card p { font-size: 0.82rem; color: var(--text-muted); margin: 0; }

/* ---------- 广告占位 ---------- */
.ad-slot { min-height: 90px; display: flex; align-items: center; justify-content: center; border-radius: 8px; background: var(--bg-soft); border: 1px dashed var(--border); font-size: 0.8rem; color: var(--text-muted); margin: 1.25rem 0; overflow: hidden; }
.ad-slot .ad-label { opacity: 0.7; }

/* ---------- 首页 Hero ---------- */
.hero { text-align: center; padding: 4rem 1rem 3rem; }
.hero h1 { font-size: 2.4rem; line-height: 1.2; margin-bottom: 1rem; }
.hero p { font-size: 1.1rem; color: var(--text-muted); max-width: 640px; margin: 0 auto 1.5rem; }
.hero .sub-note { font-size: 0.85rem; color: var(--text-muted); }
@media (max-width: 640px) { .hero h1 { font-size: 1.7rem; } }

/* 工具卡片网格 */
.tool-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.25rem; }
@media (max-width: 900px) { .tool-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 600px) { .tool-grid { grid-template-columns: 1fr; } }
.tool-card {
  display: block; background: var(--card); border: 1px solid var(--border); border-radius: 12px;
  padding: 1.5rem; text-decoration: none; color: var(--text);
  transition: box-shadow 0.15s ease, transform 0.15s ease;
}
.tool-card:hover { box-shadow: var(--shadow-md); transform: translateY(-3px); }
.tool-card h3 { font-size: 1.05rem; color: var(--primary); margin-bottom: 0.5rem; }
.tool-card p { font-size: 0.88rem; color: var(--text-muted); margin-bottom: 0.75rem; }

/* 区块标题 */
.section-title { font-size: 1.5rem; margin: 2.5rem 0 1.25rem; text-align: center; }
.section-sub { text-align: center; color: var(--text-muted); font-size: 0.95rem; margin-bottom: 2rem; }

/* 价值要点 */
.feature-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1.25rem; }
@media (max-width: 900px) { .feature-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 600px) { .feature-grid { grid-template-columns: 1fr; } }
.feature-item { text-align: center; padding: 1.25rem; }
.feature-item .icon { font-size: 1.8rem; margin-bottom: 0.5rem; }
.feature-item h4 { font-size: 0.98rem; margin-bottom: 0.35rem; }
.feature-item p { font-size: 0.85rem; color: var(--text-muted); }

/* ---------- 页脚 ---------- */
.footer { border-top: 1px solid var(--border); background: var(--bg-soft); padding: 2.5rem 0 1.5rem; margin-top: 3rem; }
.footer-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 2rem; }
@media (max-width: 768px) { .footer-grid { grid-template-columns: 1fr; } }
.footer h4 { font-size: 0.95rem; margin-bottom: 0.75rem; }
.footer ul { list-style: none; }
.footer ul li { margin-bottom: 0.4rem; }
.footer a { color: var(--text-muted); text-decoration: none; font-size: 0.88rem; }
.footer a:hover { color: var(--primary); }
.footer-bottom { border-top: 1px solid var(--border); margin-top: 2rem; padding-top: 1rem; font-size: 0.82rem; color: var(--text-muted); text-align: center; }

/* ---------- 通用工具类 ---------- */
.text-center { text-align: center; }
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mb-2 { margin-bottom: 1rem; }
.muted { color: var(--text-muted); }
.hidden { display: none !important; }