/* 南京科进 - 产品专题入口页 | 苹果风格设计 */

:root {
  --primary: #0066cc;
  --primary-dark: #004d99;
  --text: #1d1d1f;
  --text-secondary: #6e6e73;
  --text-tertiary: #86868b;
  --bg: #ffffff;
  --bg-secondary: #f5f5f7;
  --border: rgba(0,0,0,0.08);
  --radius: 18px;
  --shadow: 0 4px 20px rgba(0,0,0,0.06);
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { font-family: -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'SF Pro Text', 'Microsoft YaHei', sans-serif; color: var(--text); line-height: 1.5; background: var(--bg-secondary); -webkit-font-smoothing: antialiased; }
a { text-decoration: none; color: inherit; }
img { max-width: 100%; display: block; }
.container { max-width: 1500px; margin: 0 auto; padding: 0 48px; }

/* 顶部导航 */
.header { background: rgba(255,255,255,0.72); backdrop-filter: saturate(180%) blur(20px); -webkit-backdrop-filter: saturate(180%) blur(20px); position: sticky; top: 0; z-index: 100; border-bottom: 1px solid var(--border); }
.header .container { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.header-left { display: flex; align-items: center; }
.logo { display: flex; align-items: center; gap: 12px; }
.logo img { height: 36px; }
.logo-text { display: flex; flex-direction: column; }
.logo-name { font-size: 18px; font-weight: 600; color: var(--text); letter-spacing: -0.02em; line-height: 1.2; }
.logo-slogan { font-size: 11px; color: var(--text-tertiary); letter-spacing: 0.02em; }
.header-right { display: flex; align-items: center; gap: 32px; }
.header-nav { display: flex; align-items: center; gap: 28px; }
.header-nav a { font-size: 14px; color: var(--text-secondary); font-weight: 500; transition: color 0.2s; }
.header-nav a:hover { color: var(--primary); }
.phone-btn { display: flex; align-items: center; gap: 8px; background: var(--primary); color: #fff; padding: 10px 22px; border-radius: 980px; font-size: 14px; font-weight: 500; transition: all 0.2s; }
.phone-btn svg { width: 16px; height: 16px; }
.phone-btn:hover { background: var(--primary-dark); transform: scale(1.02); }

/* Hero区域 */
.hero { background: linear-gradient(180deg, #c3d1df 0%, var(--bg-secondary) 100%); padding: 80px 0 80px; text-align: center; }
.hero h1 { font-size: 56px; font-weight: 700; letter-spacing: -0.03em; margin-bottom: 16px; background: linear-gradient(135deg, var(--text) 0%, var(--text-secondary) 100%); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.hero p { font-size: 21px; color: var(--text-secondary); font-weight: 400; letter-spacing: -0.01em; }

/* 主体内容 */
.main { padding: 0px 0 80px; }

/* 分类卡片 */
.category { background: var(--bg); border-radius: var(--radius); margin-bottom: 16px; overflow: hidden; box-shadow: var(--shadow); border: 1px solid var(--border); }
.category-header { display: flex; align-items: center; padding: 24px 32px; cursor: pointer; user-select: none; transition: background 0.15s; }
.category-header:hover { /*background: rgba(0,0,0,0.02);*/ }
.category-header h2 { font-size: 20px; font-weight: 600; flex: 1; position: relative; padding-left: 16px; }
.category-header h2::before { content: ''; position: absolute; left: 0; top: 50%; transform: translateY(-50%); width: 4px; height: 20px; background: linear-gradient(180deg, var(--primary) 0%, #3399ff 100%); border-radius: 2px; }
.category-header .count { font-size: 14px; color: var(--text-tertiary); margin-right: 16px; }
.category-header .arrow { display: flex; align-items: center; justify-content: center; width: 28px; height: 28px; color: var(--text-tertiary); transition: transform 0.25s; }
.category-header .arrow svg { width: 18px; height: 18px; }
.category.open .category-header .arrow { transform: rotate(180deg); }

.category-content { max-height: 0; overflow: hidden; transition: max-height 0.3s ease-out; }
.category.open .category-content { max-height: 1000px; }

/* 专题项 */
.items-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 16px; padding: 0 32px 24px; }
.item { display: flex; flex-direction: column; padding: 20px 24px; background: var(--bg-secondary); border-radius: 12px; transition: all 0.2s; position: relative; }
.item:hover { background: #e8e8ed; transform: translateY(-1px); }
.item-title { font-size: 16px; font-weight: 600; color: var(--text); margin-bottom: 4px; }
.item-desc { font-size: 14px; color: var(--text-secondary); }
.item-arrow { position: absolute; right: 20px; top: 50%; transform: translateY(-50%); color: var(--text-tertiary); font-size: 18px; opacity: 0; transition: opacity 0.2s; }
.item:hover .item-arrow { opacity: 1; }

.empty-tip { padding: 24px 32px; text-align: center; color: var(--text-tertiary); font-size: 15px; }

/* 页脚 */
.footer { background: var(--text); color: rgba(255,255,255,0.8); padding: 60px 0 32px; }
.footer-main { display: flex; justify-content: space-between; margin-bottom: 40px; }
.footer-info { max-width: 400px; }
.footer-logo { height: 32px; filter: brightness(-1) invert(1); margin-bottom: 16px; }
.footer-info p { font-size: 14px; line-height: 1.7; opacity: 0.7; }
.footer-contact p { font-size: 14px; margin-bottom: 8px; opacity: 0.7; }
.footer-contact p:first-child { font-size: 15px; opacity: 1; margin-bottom: 16px; }
.footer-contact a { color: #fff; text-decoration: underline; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,0.1); padding-top: 24px; text-align: center; }
.footer-bottom p { font-size: 13px; opacity: 0.5; }
.footer-bottom a { color: rgba(255,255,255,0.7); }

/* 侧边按钮 */
.side-buttons { position: fixed; right: 24px; bottom: 24px; display: flex; flex-direction: column; gap: 12px; z-index: 99; }
.side-btn { display: flex; align-items: center; justify-content: center; gap: 8px; width: 48px; height: 48px; background: var(--bg); border: 1px solid var(--border); border-radius: 50%; cursor: pointer; transition: all 0.2s; box-shadow: 0 4px 16px rgba(0,0,0,0.08); }
.side-btn svg { width: 20px; height: 20px; color: var(--text-secondary); }
.side-btn:hover { background: var(--primary); border-color: var(--primary); }
.side-btn:hover svg { color: #fff; }
.side-consult { width: auto; padding: 0 20px; border-radius: 24px; background: var(--primary); border-color: var(--primary); }
.side-consult svg { color: #fff; }
.side-consult span { color: #fff; font-size: 14px; font-weight: 500; white-space: nowrap; }
.side-consult:hover { background: var(--primary-dark); transform: translateY(-2px); }
.side-top { opacity: 0; visibility: hidden; transform: translateY(10px); }
.side-top.show { opacity: 1; visibility: visible; transform: translateY(0); }

/* 响应式 */
@media (max-width: 900px) {
  .container { padding: 0 24px; }
  .header-nav { display: none; }
  .header .container { height: 60px; }
  .logo-slogan { display: none; }
  .hero { padding: 70px 0 60px; }
  .hero h1 { font-size: 40px; }
  .hero p { font-size: 17px; }
  .items-grid { grid-template-columns: 1fr; }
  .category-header { padding: 20px 24px; }
  .category-header h2 { font-size: 17px; }
  .category-header .icon { width: 36px; height: 36px; }
  .items-grid { padding: 0 24px 20px; }
  .footer-main { flex-direction: column; gap: 32px; }
}

@media (max-width: 600px) {
  .container { padding: 0 20px; }
  .logo-name { font-size: 16px; }
  .logo img { height: 32px; }
  .phone-btn span { display: none; }
  .phone-btn { padding: 10px; border-radius: 50%; }
  .phone-btn svg { width: 18px; height: 18px; }
  .hero h1 { font-size: 32px; }
  .hero p { font-size: 15px; }
  .main { padding: 40px 0; }
  .category-header { padding: 18px 20px; }
  .category-header .count { display: none; }
  .items-grid { padding: 0 20px 16px; }
  .item { padding: 16px 20px; }
}