:root {
    --primary-color: #232946;
    --secondary-color: #667eea;
    --accent-color: #764ba2;
    --text-color: #fff;
    --background-color: #181f2a;
    --card-bg: #fff;
    --card-shadow: 0 4px 24px rgba(110,168,254,0.10);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Arial', sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background: linear-gradient(135deg, #232946 0%, #181f2a 100%);
    min-height: 100vh;
}

.header {
    background-color: var(--primary-color);
    padding: 1.2rem 2rem;
    color: #fff;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
    height: 60px;
}

.logo {
    color: #fff;
    font-size: 1.8rem;
    font-weight: bold;
    letter-spacing: 2px;
    display: flex;
    align-items: center;
}

.logo a {
    color: #fff !important;
    text-decoration: none;
    font-weight: bold;
    font-size: 1.8rem;
    letter-spacing: 2px;
    transition: all 0.3s ease;
    padding: 0.5rem 1rem;
    border-radius: 8px;
}

.logo a:hover {
    color: #fff !important;
    text-decoration: none;
    background: rgba(255,255,255,0.1);
    transform: translateY(-1px);
}

.nav-menu {
    display: flex;
    list-style: none;
    align-items: center;
    gap: 0.5rem;
    margin: 0;
    padding: 0;
}

.nav-menu li {
    margin: 0;
    padding: 0;
}

.nav-menu li a {
    color: #fff;
    text-decoration: none;
    padding: 0.8rem 1.2rem;
    border-radius: 20px;
    transition: all 0.3s ease;
    font-size: 1rem;
    font-weight: 500;
    display: block;
    white-space: nowrap;
}

.nav-menu li a:hover, .nav-menu li a.active {
    background: var(--secondary-color);
    color: #fff;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(102,126,234,0.3);
}

.main-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
}

.hero {
    text-align: center;
    padding: 4rem 0 2rem 0;
    color: #fff;
}

.hero h1 {
    font-size: 2.7rem;
    margin-bottom: 1rem;
    color: #fff;
    letter-spacing: 1px;
}

.hero p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    color: #c7d0e0;
}

.features {
    padding: 2rem 0 4rem 0;
}

.features h2 {
    text-align: center;
    margin-bottom: 3rem;
    color: #fff;
    letter-spacing: 1px;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.feature-card {
    background: var(--card-bg);
    padding: 2rem;
    border-radius: 16px;
    box-shadow: var(--card-shadow);
    border: 1.5px solid #e1e5e9;
    transition: box-shadow 0.3s, border 0.3s, transform 0.2s;
    position: relative;
}

.feature-card h3 {
    margin-bottom: 1rem;
    color: var(--secondary-color);
    font-size: 1.3rem;
    letter-spacing: 1px;
}

.feature-card p {
    color: #232946;
    font-size: 1rem;
    line-height: 1.7;
}

.feature-card:hover {
    box-shadow: 0 8px 32px rgba(102,126,234,0.18);
    border: 1.5px solid var(--secondary-color);
    transform: translateY(-4px) scale(1.03);
}

.cta-button {
    padding: 1rem 2rem;
    font-size: 1.1rem;
    background: linear-gradient(90deg, var(--secondary-color), var(--accent-color));
    color: #fff;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: background 0.3s, box-shadow 0.3s;
    box-shadow: 0 2px 8px rgba(102,126,234,0.10);
}

.cta-button:hover {
    background: linear-gradient(90deg, var(--accent-color), var(--secondary-color));
    box-shadow: 0 4px 16px rgba(102,126,234,0.18);
}

.footer {
    background-color: var(--primary-color);
    color: #fff;
    text-align: center;
    padding: 1rem;
    margin-top: 2rem;
    letter-spacing: 1px;
    font-size: 1rem;
    box-shadow: 0 -2px 8px rgba(0,0,0,0.08);
}

@media (max-width: 900px) {
    .main-content {
        padding: 1rem;
    }
    .feature-card {
        padding: 1.2rem;
    }
    
    .nav-bar {
        height: 50px;
    }
    
    .logo a {
        font-size: 1.6rem;
        padding: 0.4rem 0.8rem;
    }
    
    .nav-menu li a {
        padding: 0.6rem 1rem;
        font-size: 0.95rem;
    }
}
@media (max-width: 600px) {
    .main-content {
        padding: 0.5rem;
    }
    .feature-card {
        padding: 1rem;
    }
    .hero h1 {
        font-size: 1.5rem;
    }
    .features h2 {
        font-size: 1.2rem;
    }
    
    .header {
        padding: 1rem 1rem;
    }
    
    .nav-bar {
        height: 45px;
    }
    
    .logo a {
        font-size: 1.4rem;
        padding: 0.3rem 0.6rem;
    }
    
    .nav-menu li a {
        padding: 0.5rem 0.8rem;
        font-size: 0.9rem;
    }
    
    .nav-user .user-info {
        padding: 0.4rem 0.8rem;
        font-size: 0.9rem;
    }
    
    .logout-btn {
        padding: 0.4rem 0.8rem;
        font-size: 0.85rem;
    }
}

/* 用户信息和登出按钮样式 */
.nav-user {
    display: flex;
    align-items: center;
}

.nav-user .user-info {
    display: flex;
    align-items: center;
    gap: 8px;
    background: rgba(102,126,234,0.15);
    border-radius: 20px;
    padding: 0.6rem 1rem;
    font-size: 1rem;
    color: #fff;
    transition: all 0.3s ease;
    border: 1px solid rgba(102,126,234,0.2);
}

.nav-user .user-info:hover {
    background: rgba(102,126,234,0.25);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(102,126,234,0.2);
}

.user-avatar {
    font-size: 1.2em;
    color: #fff;
}

.user-name {
    font-weight: 600;
    color: #fff;
    font-size: 0.95rem;
}

.logout-btn {
    background: linear-gradient(90deg, #667eea, #764ba2);
    color: #fff;
    border: none;
    padding: 0.5rem 1rem;
    border-radius: 16px;
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 500;
    transition: all 0.3s ease;
    margin-left: 0.5rem;
    box-shadow: 0 2px 8px rgba(102,126,234,0.2);
}

.logout-btn:hover {
    background: linear-gradient(90deg, #764ba2, #667eea);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(102,126,234,0.3);
}

/* 管理员下拉菜单样式 */
.user-dropdown {
    position: relative;
    display: inline-block;
}

.user-dropdown .user-info {
    display: flex;
    align-items: center;
    gap: 8px;
    background: rgba(102,126,234,0.15);
    border-radius: 20px;
    padding: 0.6rem 1rem;
    font-size: 1rem;
    color: #fff;
    transition: all 0.3s ease;
    border: 1px solid rgba(102,126,234,0.2);
    cursor: pointer;
}

.user-dropdown .user-info:hover {
    background: rgba(102,126,234,0.25);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(102,126,234,0.2);
}

.dropdown-arrow {
    font-size: 0.8em;
    transition: transform 0.3s ease;
    margin-left: 4px;
}

.user-dropdown .user-info:hover .dropdown-arrow {
    transform: rotate(180deg);
}

.dropdown-menu {
    position: absolute;
    top: 100%;
    right: 0;
    background: white;
    border-radius: 12px;
    box-shadow: 0 8px 32px rgba(0,0,0,0.15);
    border: 1px solid #e1e5e9;
    min-width: 180px;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: all 0.3s ease;
    margin-top: 8px;
}

.dropdown-menu.show {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.dropdown-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    color: #232946;
    text-decoration: none;
    transition: all 0.3s ease;
    cursor: pointer;
    font-size: 0.95rem;
    font-weight: 500;
}

.dropdown-item:hover {
    background: #f8f9fa;
    color: var(--secondary-color);
}

.dropdown-item:first-child {
    border-radius: 12px 12px 0 0;
}

.dropdown-item:last-child {
    border-radius: 0 0 12px 12px;
}

.dropdown-icon {
    font-size: 1.1em;
    width: 20px;
    text-align: center;
}

.dropdown-divider {
    height: 1px;
    background: #e1e5e9;
    margin: 4px 0;
}

/* 响应式设计 */
@media (max-width: 600px) {
    .dropdown-menu {
        min-width: 160px;
        right: -10px;
    }
    
    .dropdown-item {
        padding: 10px 14px;
        font-size: 0.9rem;
    }
    
    .user-dropdown .user-info {
        padding: 0.5rem 0.8rem;
        font-size: 0.9rem;
    }
}

.content-card .grid-3 p,
.content-card .grid-3 h4 {
    color: #222 !important;
}

/* 新增更细致的移动端适配 */
@media (max-width: 600px) {
    .main-content {
        padding: 0.2rem;
    }
    .feature-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    .feature-card {
        padding: 0.7rem;
        margin-bottom: 1rem;
    }
    .footer {
        font-size: 0.9rem;
        padding: 0.5rem;
    }
    .cta-button, .btn-primary, .btn-secondary {
        width: 100%;
        font-size: 1rem;
        padding: 0.7rem 0;
        margin-bottom: 0.5rem;
    }
    .form-control {
        width: 100%;
        font-size: 1rem;
    }
    .content-card {
        padding: 1rem 0.5rem;
        margin-bottom: 1rem;
    }
    .grid-2, .grid-3 {
        display: block;
    }
    .page-title, .hero h1 {
        font-size: 1.2rem;
    }
}
@media (max-width: 400px) {
    .logo a {
        font-size: 1.1rem;
        padding: 0.2rem 0.3rem;
    }
    .feature-card h3 {
        font-size: 1rem;
    }
    .footer {
        font-size: 0.8rem;
    }
    .btn-primary, .btn-secondary {
        font-size: 0.9rem;
    }
}