/* ===== 全局重置 ===== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --primary: #1a73e8;
  --primary-hover: #1557b0;
  --bg: #f8fafc;
  --text: #1e293b;
  --text-muted: #64748b;
  --border: #e2e8f0;
  --card-shadow: 0 4px 20px -2px rgba(15, 23, 42, 0.05);
  --card-hover: 0 20px 40px -4px rgba(15, 23, 42, 0.1);
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a { text-decoration: none; color: inherit; }
.container { width: min(1120px, 92%); margin: 0 auto; }

/* ===== 顶部导航 ===== */
.header {
  background: rgba(255, 255, 255, 0.95);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(10px);
}
.nav-box { display: flex; align-items: center; justify-content: space-between; height: 72px; gap: 20px; }
.logo { font-size: 24px; font-weight: 800; color: var(--primary); letter-spacing: -0.5px; }
nav { display: flex; gap: 32px; font-size: 15px; font-weight: 500; color: var(--text-muted); }
nav a { transition: color 0.2s; }
nav a:hover, nav a.active { color: var(--primary); }

/* ===== 按钮 ===== */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 10px 20px; border-radius: 10px; font-size: 14px; font-weight: 600;
  border: none; cursor: pointer; transition: all 0.25s ease; gap: 8px;
}
.btn-primary { background: var(--primary); color: #fff; box-shadow: 0 4px 12px rgba(26, 115, 232, 0.25); }
.btn-primary:hover { background: var(--primary-hover); transform: translateY(-2px); box-shadow: 0 6px 20px rgba(26, 115, 232, 0.35); }
.btn-outline { background: #fff; border: 1px solid var(--border); color: var(--text); }
.btn-outline:hover { border-color: var(--primary); color: var(--primary); background: #f0f7ff; }
.btn-lg { padding: 14px 32px; font-size: 16px; border-radius: 12px; }
.btn-block { width: 100%; padding: 14px; font-size: 16px; border-radius: 12px; }

/* ===== 首页轮播图 ===== */
.heroSwiper { width: 100%; height: 550px; }
.swiper-slide { display: flex; align-items: center; justify-content: center; color: #fff; text-align: center; }
.slide-1 { background: linear-gradient(135deg, #0f172a 0%, #1e3a8a 100%); }
.slide-2 { background: linear-gradient(135deg, #1e3a8a 0%, #3b82f6 100%); }
.slide-content h1 { font-size: 52px; font-weight: 800; margin-bottom: 20px; letter-spacing: -1px; line-height: 1.2; }
.slide-content p { font-size: 20px; opacity: 0.9; margin-bottom: 40px; font-weight: 400; }
.swiper-pagination-bullet { background: #fff !important; opacity: 0.5; }
.swiper-pagination-bullet-active { opacity: 1; width: 24px; border-radius: 4px; }

/* ===== 首页区块与卡片 ===== */
.section { padding: 80px 0; }
.section-gray { background: #f1f5f9; }
h2 { text-align: center; font-size: 36px; font-weight: 800; margin-bottom: 16px; letter-spacing: -0.5px; }
.section-subtitle { text-align: center; color: var(--text-muted); font-size: 18px; margin-bottom: 50px; }
.cards { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.card { background: #fff; border: 1px solid var(--border); border-radius: 16px; padding: 32px 24px; box-shadow: var(--card-shadow); transition: all 0.3s ease; }
.card:hover { transform: translateY(-6px); box-shadow: var(--card-hover); border-color: #cbd5e1; }
.card-icon { font-size: 40px; margin-bottom: 20px; }
.card h3 { font-size: 20px; margin-bottom: 12px; font-weight: 700; }
.card p { color: var(--text-muted); font-size: 15px; line-height: 1.7; }

/* ===== 媒体 Logo 墙 / 媒体卡片 ===== */
.media-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.media-logo {
  background: #fff; border: 1px solid var(--border); border-radius: 12px;
  padding: 40px 20px; text-align: center; font-weight: 700; color: var(--text-muted);
  font-size: 16px; box-shadow: var(--card-shadow); transition: all 0.3s ease; cursor: pointer;
}
.media-logo:hover { color: var(--primary); border-color: var(--primary); transform: translateY(-4px); box-shadow: var(--card-hover); }
.media-card { background: #fff; border: 1px solid var(--border); border-radius: 16px; padding: 28px; box-shadow: var(--card-shadow); transition: all 0.3s ease; }
.media-card:hover { border-color: var(--primary); transform: translateY(-4px); box-shadow: var(--card-hover); }

/* ===== 认证页面 ===== */
.auth-page { min-height: 100vh; display: flex; align-items: center; justify-content: center; background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%); padding: 30px 16px; }
.auth-box { width: 100%; max-width: 440px; background: #fff; border-radius: 24px; padding: 48px 40px; box-shadow: 0 30px 80px -20px rgba(0, 0, 0, 0.4); }
.auth-box h2 { font-size: 28px; margin-top: 24px; margin-bottom: 8px; text-align: left; }
.auth-box .subtitle { text-align: left; margin-bottom: 32px; font-size: 15px; }
.form-group { margin-bottom: 20px; }
.form-group label { display: block; font-size: 14px; font-weight: 600; margin-bottom: 8px; color: var(--text); }
.form-group input, .form-group select, .form-group textarea {
  width: 100%; padding: 12px 16px; border: 1.5px solid var(--border);
  border-radius: 12px; font-size: 15px; outline: none; transition: all 0.2s; background: #f8fafc; font-family: inherit;
}
.form-group input:focus, .form-group select:focus, .form-group textarea:focus {
  border-color: var(--primary); background: #fff; box-shadow: 0 0 0 4px rgba(26, 115, 232, 0.1);
}
.strength { display: flex; gap: 6px; margin-top: 10px; }
.strength span { flex: 1; height: 4px; background: #e2e8f0; border-radius: 2px; transition: 0.3s; }
.strength.weak span:nth-child(1) { background: #ef4444; }
.strength.medium span:nth-child(1), .strength.medium span:nth-child(2) { background: #f59e0b; }
.strength.strong span { background: #10b981; }
.agree { display: flex; gap: 10px; align-items: flex-start; font-size: 13px; color: var(--text-muted); margin: 16px 0 24px; }
.switch { text-align: center; margin-top: 24px; font-size: 14px; color: var(--text-muted); }
.switch a { color: var(--primary); font-weight: 600; }

/* ===== 滚动动画 ===== */
.fade-in-up { opacity: 0; transform: translateY(30px); transition: opacity 0.8s ease-out, transform 0.8s ease-out; }
.fade-in-up.visible { opacity: 1; transform: translateY(0); }

/* ===== 向下滚动箭头 ===== */
.scroll-down { position: absolute; bottom: 30px; left: 50%; transform: translateX(-50%); color: #fff; z-index: 10; animation: bounce 2s infinite; opacity: 0.7; }
.scroll-down:hover { opacity: 1; }
@keyframes bounce { 0%, 20%, 50%, 80%, 100% { transform: translateX(-50%) translateY(0); } 40% { transform: translateX(-50%) translateY(-10px); } 60% { transform: translateX(-50%) translateY(-5px); } }

/* ===== 热门媒体分类标签 ===== */
.filter-tabs { display: flex; justify-content: center; gap: 12px; margin-bottom: 40px; flex-wrap: wrap; }
.filter-tab { padding: 8px 20px; border-radius: 20px; border: 1px solid var(--border); background: #fff; color: var(--text-muted); font-size: 14px; font-weight: 500; cursor: pointer; transition: all 0.3s; }
.filter-tab:hover { border-color: var(--primary); color: var(--primary); }
.filter-tab.active { background: var(--primary); border-color: var(--primary); color: #fff; box-shadow: 0 4px 12px rgba(26, 115, 232, 0.3); }

/* ===== 专业页脚 ===== */
.footer { background: #0f172a; color: #fff; padding: 60px 0 0 0; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1.5fr; gap: 40px; padding-bottom: 40px; }
.footer h4 { font-size: 16px; margin-bottom: 20px; color: #fff; }
.footer ul { list-style: none; }
.footer ul li { margin-bottom: 12px; font-size: 14px; color: #94a3b8; }
.footer ul li a { color: #94a3b8; transition: color 0.2s; }
.footer ul li a:hover { color: #fff; }
.footer-bottom { border-top: 1px solid #1e293b; padding: 24px 0; text-align: center; font-size: 14px; color: #64748b; }

/* ===== 响应式 ===== */
@media (max-width: 800px) {
  .cards { grid-template-columns: repeat(2, 1fr); }
  .media-grid { grid-template-columns: repeat(2, 1fr); }
  .heroSwiper { height: 450px; }
  .slide-content h1 { font-size: 36px; }
  .slide-content p { font-size: 16px; }
  nav { display: none; }
  .auth-box { padding: 32px 24px; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 520px) {
  .cards { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
}