/* SiteOS 默认皮肤样式。语义化类名，BEM 风格，无框架依赖 */
:root {
  --c-primary: #0f5fa6;
  --c-primary-dark: #0b467c;
  --c-text: #1f2933;
  --c-muted: #64748b;
  --c-border: #e2e8f0;
  --c-bg-alt: #f7f9fc;
  --radius: 8px;
  --container: 1180px;
}

*, *::before, *::after { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, "Segoe UI", "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--c-text);
  line-height: 1.65;
  font-size: 16px;
}

img { max-width: 100%; height: auto; display: block; }
a { color: var(--c-primary); text-decoration: none; }
a:hover { text-decoration: underline; }

.container { max-width: var(--container); margin: 0 auto; padding: 0 20px; }
.container.narrow { max-width: 820px; }
.center { text-align: center; }

/* 头部 */
.site-header {
  border-bottom: 1px solid var(--c-border);
  background: #fff;
  position: sticky;
  top: 0;
  z-index: 20;
}
.header-inner { display: flex; align-items: center; gap: 24px; min-height: 68px; flex-wrap: wrap; }
.brand { font-size: 20px; font-weight: 700; color: var(--c-text); }
.main-nav { display: flex; gap: 18px; flex-wrap: wrap; margin-left: auto; }
.main-nav a { color: var(--c-text); font-size: 15px; }
.main-nav a:hover { color: var(--c-primary); text-decoration: none; }
.lang-switch { display: flex; gap: 8px; font-size: 13px; }
.lang-switch a { color: var(--c-muted); text-transform: uppercase; }
.lang-switch a.active { color: var(--c-primary); font-weight: 700; }

/* Hero */
.hero {
  padding: 72px 0;
  background: linear-gradient(135deg, #eef4fb 0%, #ffffff 100%);
  text-align: center;
}
.hero h1 { font-size: 38px; margin: 0 0 14px; line-height: 1.25; }
.hero .lead { font-size: 18px; color: var(--c-muted); max-width: 720px; margin: 0 auto 26px; }

/* 按钮 */
.btn {
  display: inline-block;
  padding: 11px 26px;
  background: var(--c-primary);
  color: #fff;
  border-radius: var(--radius);
  border: 1px solid var(--c-primary);
  font-size: 15px;
  cursor: pointer;
  transition: background .18s;
}
.btn:hover { background: var(--c-primary-dark); text-decoration: none; }
.btn-ghost { background: transparent; color: var(--c-primary); margin-left: 10px; }
.btn-ghost:hover { background: #eaf2fa; }

/* 区块 */
.section { padding: 56px 0; }
.section-alt { background: var(--c-bg-alt); }
.section h1 { font-size: 30px; margin: 0 0 26px; }
.section h2 { font-size: 24px; margin: 0 0 22px; }

/* 网格卡片 */
.grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 22px; }
.grid-sm { grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); }
.card {
  display: block;
  border: 1px solid var(--c-border);
  border-radius: var(--radius);
  padding: 18px;
  color: var(--c-text);
  background: #fff;
  transition: box-shadow .18s, transform .18s;
}
.card:hover { box-shadow: 0 6px 22px rgba(15, 95, 166, .12); transform: translateY(-2px); text-decoration: none; }
.card img { border-radius: 6px; margin-bottom: 12px; aspect-ratio: 4/3; object-fit: cover; width: 100%; }
.card h3 { font-size: 17px; margin: 0 0 8px; }
.card p { color: var(--c-muted); font-size: 14px; margin: 0; }
.card time { color: var(--c-muted); font-size: 13px; }
.tag {
  display: inline-block; margin-top: 10px; padding: 2px 10px;
  background: #eaf2fa; color: var(--c-primary); border-radius: 12px; font-size: 12px;
}

/* 列表 */
.list-item { padding: 20px 0; border-bottom: 1px solid var(--c-border); }
.list-item h3 { margin: 0 0 8px; font-size: 19px; }
.list-item p { color: var(--c-muted); margin: 0 0 8px; }
.list-item time, .meta { color: var(--c-muted); font-size: 13px; }

/* 详情 */
.breadcrumb { font-size: 13px; color: var(--c-muted); margin-bottom: 22px; }
.detail-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; align-items: start; }
.detail-media img { border-radius: var(--radius); width: 100%; }
.detail-info h1 { margin: 0 0 14px; font-size: 28px; }
.detail-info .lead { color: var(--c-muted); margin-bottom: 18px; }
.specs { display: grid; grid-template-columns: 120px 1fr; gap: 8px 16px; margin: 0 0 24px; }
.specs dt { color: var(--c-muted); font-size: 14px; }
.specs dd { margin: 0; font-weight: 600; font-size: 14px; }
.detail-body { margin-top: 40px; max-width: 860px; }
.detail-cover { border-radius: var(--radius); margin: 20px 0; }

/* 表单 */
.form { display: grid; gap: 16px; margin-top: 24px; }
.form label { display: grid; gap: 6px; font-size: 14px; font-weight: 600; }
.form input, .form textarea {
  padding: 10px 12px; border: 1px solid var(--c-border);
  border-radius: 6px; font-size: 15px; font-family: inherit; font-weight: 400;
}
.form input:focus, .form textarea:focus { outline: 2px solid #bfdbfe; border-color: var(--c-primary); }
.field-error { color: #b91c1c; font-size: 13px; }
.product-ref { padding: 12px 16px; background: var(--c-bg-alt); border-radius: 6px; margin: 18px 0; font-size: 14px; }

/* 提示 */
.alert { padding: 14px 18px; border-radius: var(--radius); margin: 18px 0; font-size: 15px; }
.alert-ok { background: #ecfdf5; color: #065f46; border: 1px solid #a7f3d0; }
.alert-err { background: #fef2f2; color: #991b1b; border: 1px solid #fecaca; }

/* FAQ */
.faq-item { border-bottom: 1px solid var(--c-border); padding: 16px 0; }
.faq-item summary { font-weight: 600; cursor: pointer; font-size: 16px; }
.faq-answer { color: var(--c-muted); padding-top: 12px; }

/* 分页与过滤 */
.filter-bar { display: flex; gap: 12px; flex-wrap: wrap; margin-bottom: 26px; }
.filter-bar a {
  padding: 6px 16px; border: 1px solid var(--c-border);
  border-radius: 20px; font-size: 14px; color: var(--c-text);
}
.filter-bar a.active { background: var(--c-primary); color: #fff; border-color: var(--c-primary); }
.pagination { display: flex; gap: 16px; justify-content: center; margin-top: 36px; font-size: 14px; }

.empty { color: var(--c-muted); }

/* 页脚 */
.site-footer {
  border-top: 1px solid var(--c-border);
  padding: 30px 0;
  color: var(--c-muted);
  font-size: 14px;
  text-align: center;
}
.site-footer p { margin: 4px 0; }

/* 移动端 */
@media (max-width: 820px) {
  .hero { padding: 48px 0; }
  .hero h1 { font-size: 27px; }
  .detail-grid { grid-template-columns: 1fr; gap: 24px; }
  .main-nav { margin-left: 0; gap: 14px; }
  .header-inner { padding: 12px 0; }
}