/* ========== 全局样式 ========== */
:root {
  --primary-color: #1a5fb4;
  --primary-dark: #0e4a8c;
  --text-color: #333333;
  --text-light: #666666;
  --border-color: #e0e0e0;
  --background-light: #f8f9fa;
  --white: #ffffff;
  --shadow-light: 0 2px 12px rgba(0, 0, 0, 0.08);
  --shadow-medium: 0 4px 20px rgba(0, 0, 0, 0.1);
}

body {
  margin: 0;
  font-family: 'Inter', 'Helvetica Neue', 'Segoe UI', Arial, sans-serif;
  color: var(--text-color);
  background-color: var(--background-light);
  line-height: 1.6;
}

/* ========== 页头样式 ========== */
.sticky-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--white);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 40px;
  box-shadow: var(--shadow-light);
  border-bottom: 1px solid var(--border-color);
  height: 60px;
}

/* Logo 区域 */
.logo {
  display: flex;
  align-items: center;
  text-decoration: none;
  gap: 12px;
  transition: transform 0.2s;
}

.logo:hover {
  transform: translateY(-1px);
}

.logo img {
  width: 36px;
  height: 36px;
  border-radius: 8px;
  filter: none; /* 移除反色滤镜 */
  border: 1px solid var(--border-color);
  padding: 4px;
  background: var(--white);
}

.site-name {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--text-color);
  letter-spacing: -0.5px;
  background: linear-gradient(135deg, var(--primary-color), #2a7de1);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* Logo和导航之间的分隔线 */
.header-divider {
  width: 1px;
  height: 30px;
  background: var(--border-color);
  margin: 0 30px;
}

/* ========== 导航链接样式 ========== */
.nav-links {
  display: flex;
  align-items: center;
  gap: 0;
  flex: 1;
  margin-left: 20px;
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 8px;
  text-decoration: none;
  color: var(--text-color);
  font-weight: 500;
  font-size: 0.95rem;
  padding: 10px 16px;
  border-radius: 6px;
  transition: all 0.3s ease;
  position: relative;
}

.nav-item:hover {
  background-color: rgba(26, 95, 180, 0.05);
  color: var(--primary-color);
}

.nav-item i {
  font-size: 0.9rem;
  color: var(--text-light);
  transition: color 0.3s;
}

.nav-item:hover i {
  color: var(--primary-color);
}

/* 当前激活状态 */
.nav-item.active {
  color: var(--primary-color);
  background-color: rgba(26, 95, 180, 0.1);
}

.nav-item.active i {
  color: var(--primary-color);
}

/* 导航项之间的分隔线 */
.nav-divider {
  color: var(--border-color);
  font-weight: 300;
  user-select: none;
  padding: 0 2px;
}

/* ========== 主内容区域 ========== */
main {
  min-height: calc(100vh - 200px);
  padding: 30px;
  max-width: 1400px;
  margin: 0 auto;
}

/* ========== 页脚样式 ========== */
.footer {
  background: #000000;
  color: #e0e0e0;
  padding: 15px 0;
  margin-top: 0px;
  text-align: center;
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 40px;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 40px;
}

.footer-section h4 {
  color: var(--white);
  font-size: 1.1rem;
  margin-bottom: 20px;
  font-weight: 600;
}

.footer-section p {
  margin: 8px 0;
  font-size: 0.9rem;
  line-height: 1.6;
}

.footer-section a {
  color: #64b5f6;
  text-decoration: none;
  transition: color 0.3s;
}

.footer-section a:hover {
  color: var(--white);
  text-decoration: underline;
}

.footer-bottom {
  text-align: center;
  padding-top: 30px;
  margin-top: 30px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  font-size: 0.85rem;
  color: #aaa;
}