/* ===== 公共样式 ===== */
* { margin: 0; padding: 0; box-sizing: border-box; }

body {
  font-family: system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
  background-color: #f8fafc;
  color: #1e293b;
  line-height: 1.6;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

.container { width: 100%; max-width: 1200px; margin: 0 auto; padding: 0 1.5rem; }
.container-narrow { width: 100%; max-width: 860px; margin: 0 auto; padding: 0 1.5rem; }

/* ===== 头部 ===== */
.site-header {
  background-color: #ffffff;
  box-shadow: 0 2px 10px rgba(0,0,0,.02);
  position: sticky; top: 0; z-index: 50;
  border-bottom: 1px solid #e2e8f0;
}
.header-inner { display: flex; align-items: center; justify-content: space-between; height: 70px; }
.logo-link { display: flex; align-items: center; gap: .5rem; text-decoration: none; color: #0f172a; font-weight: 600; font-size: 1.4rem; }
.logo-img { width: 36px; height: 36px; object-fit: contain; }
.logo-text { background: linear-gradient(135deg,#0d9488,#3b82f6); -webkit-background-clip: text; background-clip: text; color: transparent; }
.main-nav { display: flex; gap: 1.6rem; }
.nav-link { text-decoration: none; color: #334155; font-weight: 500; transition: color .2s; font-size: .95rem; white-space: nowrap; }
.nav-link:hover, .nav-link.active { color: #0d9488; }
.menu-toggle { display: none; background: none; border: none; font-size: 1.8rem; cursor: pointer; color: #0f172a; padding: 0 .5rem; }

.main-nav.active {
  display: flex; flex-direction: column; position: absolute; top: 70px; left: 0; width: 100%;
  background: #fff; padding: 1rem 1.5rem; box-shadow: 0 10px 15px -5px rgba(0,0,0,.05);
  border-bottom: 1px solid #e2e8f0; gap: 1rem;
}

/* ===== Hero ===== */
.hero { padding: 3.5rem 0; background: linear-gradient(145deg,#ffffff 0%,#f0fdfa 100%); border-bottom: 1px solid #ccfbf1; }
.hero-content { display: flex; align-items: center; justify-content: space-between; gap: 2rem; flex-wrap: wrap; }
.hero-text { flex: 1 1 400px; }
.hero-title { font-size: 3.5rem; font-weight: 700; background: linear-gradient(135deg,#0d9488,#3b82f6); -webkit-background-clip: text; background-clip: text; color: transparent; line-height: 1.2; margin-bottom: .5rem; }
.hero-subtitle { font-size: 1.5rem; color: #0f172a; font-weight: 500; margin-bottom: .75rem; }
.hero-desc { color: #475569; font-size: 1.05rem; margin-bottom: 1.5rem; }
.hero-desc strong { color: #0d9488; }
.hero-image { flex: 0 0 200px; display: flex; justify-content: center; align-items: center; }
.hero-logo { width: 100%; max-width: 220px; height: auto; filter: drop-shadow(0 15px 25px rgba(13,148,136,.2)); transition: transform .3s; }
.hero-logo:hover { transform: scale(1.02); }

/* 简版页面头 */
.page-hero { padding: 3rem 0 2.5rem; background: linear-gradient(145deg,#ffffff 0%,#f0fdfa 100%); border-bottom: 1px solid #ccfbf1; text-align: center; }
.page-hero h1 { font-size: 2.6rem; font-weight: 700; background: linear-gradient(135deg,#0d9488,#3b82f6); -webkit-background-clip: text; background-clip: text; color: transparent; margin-bottom: .75rem; }
.page-hero p { color: #475569; font-size: 1.1rem; max-width: 720px; margin: 0 auto; }

/* ===== 倒计时 ===== */
.countdown-container { display: flex; gap: 1rem; margin-bottom: 2rem; flex-wrap: wrap; }
.countdown-item { background: #fff; border-radius: 16px; padding: .75rem 1rem; min-width: 75px; text-align: center; box-shadow: 0 4px 12px rgba(13,148,136,.08); border: 1px solid #ccfbf1; }
.countdown-num { display: block; font-size: 2rem; font-weight: 700; color: #0d9488; line-height: 1.2; }
.countdown-label { font-size: .8rem; color: #64748b; text-transform: uppercase; letter-spacing: .5px; }

/* ===== 按钮 ===== */
.btn { display: inline-block; padding: .75rem 1.75rem; border-radius: 40px; font-weight: 600; text-decoration: none; transition: all .2s; cursor: pointer; border: 2px solid transparent; font-size: 1rem; text-align: center; }
.btn-primary { background: linear-gradient(135deg,#0d9488,#3b82f6); color: #fff; box-shadow: 0 8px 20px rgba(13,148,136,.25); }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 12px 24px rgba(13,148,136,.35); }
.btn-outline { background: transparent; border: 2px solid #0d9488; color: #0d9488; }
.btn-outline:hover { background: #0d9488; color: #fff; }
.hero-actions { display: flex; gap: 1rem; flex-wrap: wrap; }

/* ===== 通用 section ===== */
.section { padding: 4rem 0; }
.section-alt { background: #ffffff; }
.section-title { text-align: center; font-size: 2rem; font-weight: 600; margin-bottom: 3rem; color: #0f172a; }
.section-title::after { content: ''; display: block; width: 70px; height: 4px; background: linear-gradient(90deg,#0d9488,#3b82f6); margin: .75rem auto 0; border-radius: 4px; }

/* ===== 卡片网格 ===== */
.highlight-grid { display: grid; grid-template-columns: repeat(auto-fit,minmax(240px,1fr)); gap: 2rem; }
.highlight-card { background: #fff; padding: 2rem 1.5rem; border-radius: 28px; box-shadow: 0 8px 20px rgba(0,0,0,.02); border: 1px solid #e2e8f0; transition: all .25s; text-align: center; }
.highlight-card:hover { border-color: #99f6e4; box-shadow: 0 12px 28px rgba(13,148,136,.08); transform: translateY(-4px); }
.highlight-icon { font-size: 2.5rem; margin-bottom: 1rem; }
.highlight-card h3 { font-size: 1.35rem; margin-bottom: .75rem; color: #0f172a; }
.highlight-card p { color: #475569; font-size: .95rem; }

/* ===== 文章/列表内容 ===== */
.content-block { background: #fff; border: 1px solid #e2e8f0; border-radius: 24px; padding: 2rem; margin-bottom: 1.5rem; box-shadow: 0 4px 12px rgba(0,0,0,.02); }
.content-block h2 { font-size: 1.5rem; color: #0f172a; margin-bottom: 1rem; }
.content-block h3 { font-size: 1.15rem; color: #0f172a; margin: 1.25rem 0 .5rem; }
.content-block p { color: #475569; margin-bottom: .75rem; }
.content-block ul { padding-left: 1.25rem; color: #475569; }
.content-block li { margin-bottom: .5rem; }

/* FAQ 折叠 */
.faq-item { background: #fff; border: 1px solid #e2e8f0; border-radius: 20px; padding: 1.25rem 1.5rem; margin-bottom: 1rem; }
.faq-item summary { cursor: pointer; font-weight: 600; color: #0f172a; list-style: none; display: flex; justify-content: space-between; align-items: center; }
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after { content: '+'; font-size: 1.4rem; color: #0d9488; }
.faq-item[open] summary::after { content: '−'; }
.faq-item p { margin-top: .75rem; color: #475569; font-size: .95rem; }

/* 表格 */
.compare-table { width: 100%; border-collapse: collapse; background: #fff; border-radius: 20px; overflow: hidden; border: 1px solid #e2e8f0; }
.compare-table th, .compare-table td { padding: 1rem; text-align: left; border-bottom: 1px solid #e2e8f0; font-size: .95rem; }
.compare-table th { background: #f0fdfa; color: #0f172a; font-weight: 600; }
.compare-table tr:last-child td { border-bottom: none; }

/* 博客 */
.blog-grid { display: grid; grid-template-columns: repeat(auto-fit,minmax(280px,1fr)); gap: 1.75rem; }
.blog-card { background: #fff; border: 1px solid #e2e8f0; border-radius: 24px; overflow: hidden; transition: all .25s; }
.blog-card:hover { transform: translateY(-4px); box-shadow: 0 12px 28px rgba(13,148,136,.08); border-color: #99f6e4; }
.blog-thumb { height: 140px; background: linear-gradient(135deg,#ccfbf1,#dbeafe); display: flex; align-items: center; justify-content: center; font-size: 2.5rem; }
.blog-body { padding: 1.5rem; }
.blog-body h3 { font-size: 1.15rem; margin-bottom: .5rem; color: #0f172a; }
.blog-body p { color: #475569; font-size: .9rem; margin-bottom: 1rem; }
.blog-meta { font-size: .8rem; color: #94a3b8; }

/* ===== 下载页专用 ===== */
.download-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 2rem;
  margin-bottom: 3rem;
}
.download-card {
  background: #fff;
  border: 1px solid #e2e8f0;
  border-radius: 28px;
  padding: 2.5rem 2rem;
  text-align: center;
  box-shadow: 0 8px 20px rgba(0,0,0,.02);
  transition: all .25s;
}
.download-card:hover {
  border-color: #99f6e4;
  box-shadow: 0 12px 28px rgba(13,148,136,.08);
  transform: translateY(-4px);
}
.download-icon { font-size: 3rem; margin-bottom: 1rem; color: #0f172a; }
.download-card h3 { font-size: 1.4rem; color: #0f172a; margin-bottom: .5rem; }
.download-card p { color: #475569; font-size: .95rem; }
.download-badge { margin: 1rem 0 .5rem; }
.badge-soon {
  display: inline-block;
  background: #f0fdfa;
  color: #0d9488;
  border: 1px solid #99f6e4;
  border-radius: 40px;
  padding: .3rem 1rem;
  font-size: .85rem;
  font-weight: 600;
}
.download-note { font-size: .85rem; color: #94a3b8; margin-bottom: 1.25rem; }
.download-btn.disabled { opacity: .6; cursor: not-allowed; }
.download-faq { margin-bottom: 1.5rem; }
.safety-note {
  display: flex;
  align-items: flex-start;
  gap: .75rem;
  background: #fff;
  border: 1px solid #e2e8f0;
  border-radius: 20px;
  padding: 1.25rem 1.5rem;
  color: #475569;
  font-size: .95rem;
}
.safety-note-icon { font-size: 1.5rem; line-height: 1; }

/* ===== 页脚 ===== */
.site-footer { background: #fff; border-top: 1px solid #e2e8f0; padding: 2rem 0; margin-top: auto; }
.footer-inner { display: flex; flex-direction: column; align-items: center; gap: 1rem; text-align: center; }
.footer-brand { display: flex; align-items: center; gap: .5rem; font-weight: 600; color: #0f172a; font-size: 1.2rem; }
.footer-logo { width: 28px; height: 28px; }
.footer-copy { color: #64748b; font-size: .9rem; }
.footer-icp { font-size: .85rem; color: #94a3b8; margin-top: -.25rem; }
.footer-icp a { color: #94a3b8; text-decoration: none; transition: color .2s; }
.footer-icp a:hover { color: #0d9488; }
.footer-links { display: flex; gap: 1.5rem; margin-top: .5rem; flex-wrap: wrap; justify-content: center; }
.footer-links a { text-decoration: none; color: #475569; font-size: .9rem; }
.footer-links a:hover { color: #0d9488; }

/* ===== 响应式 ===== */
@media (max-width: 900px) {
  .main-nav { gap: 1rem; }
  .nav-link { font-size: .85rem; }
}
@media (max-width: 768px) {
  .header-inner { height: 64px; }
  .main-nav { display: none; }
  .menu-toggle { display: block; }
  .hero-title { font-size: 2.5rem; }
  .hero-subtitle { font-size: 1.25rem; }
  .hero-content { flex-direction: column-reverse; text-align: center; }
  .hero-image { flex: 0 0 auto; }
  .hero-logo { max-width: 160px; }
  .hero-actions { justify-content: center; }
  .countdown-container { justify-content: center; }
  .section-title, .page-hero h1 { font-size: 1.8rem; }
}
@media (max-width: 640px) {
  .download-grid { grid-template-columns: 1fr; gap: 1.5rem; }
}
@media (max-width: 480px) {
  .container, .container-narrow { padding: 0 1rem; }
  .countdown-item { min-width: 65px; padding: .5rem .6rem; }
  .countdown-num { font-size: 1.6rem; }
  .btn { padding: .6rem 1.25rem; font-size: .9rem; }
  .highlight-grid { grid-template-columns: 1fr; }
  .content-block { padding: 1.5rem; }
}