/* 基础样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif;
    background-color: #f5f7fa;
    color: #333;
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 导航栏 */
.navbar {
    background-color: #2c3e50;
    color: white;
    padding: 15px 0;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.navbar-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.navbar-brand a {
    color: white;
    font-size: 24px;
    font-weight: bold;
    text-decoration: none;
}

.navbar-nav {
    display: flex;
    gap: 30px;
}

.nav-link {
    color: white;
    text-decoration: none;
    padding: 8px 16px;
    border-radius: 4px;
    transition: background-color 0.3s;
}

.nav-link:hover,
.nav-link.active {
    background-color: rgba(255,255,255,0.1);
}

.navbar-actions {
    display: flex;
    gap: 10px;
    align-items: center;
}

.user-menu {
    position: relative;
    cursor: pointer;
}

.username {
    color: white;
    padding: 8px 16px;
}

.dropdown-menu {
    position: absolute;
    top: 100%;
    right: 0;
    background: white;
    border-radius: 4px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    min-width: 150px;
    display: none;
    margin-top: 5px;
}

.user-menu:hover .dropdown-menu {
    display: block;
}

.dropdown-menu a {
    display: block;
    padding: 10px 20px;
    color: #333;
    text-decoration: none;
    transition: background-color 0.3s;
}

.dropdown-menu a:hover {
    background-color: #f5f7fa;
}

/* 按钮 */
.btn {
    padding: 10px 20px;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    text-decoration: none;
    display: inline-block;
    transition: all 0.3s;
    font-size: 14px;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
}

.btn-outline {
    background: transparent;
    color: white;
    border: 1px solid white;
}

.btn-outline:hover {
    background: rgba(255,255,255,0.1);
}

.btn-block {
    width: 100%;
}

/* 消息提示 */
.messages-container {
    position: fixed;
    top: 80px;
    right: 20px;
    z-index: 1000;
}

.alert {
    padding: 15px 20px;
    margin-bottom: 10px;
    border-radius: 4px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    min-width: 300px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}

.alert-success {
    background-color: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.alert-error {
    background-color: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

.alert-info {
    background-color: #d1ecf1;
    color: #0c5460;
    border: 1px solid #bee5eb;
}

.close-btn {
    background: none;
    border: none;
    font-size: 20px;
    cursor: pointer;
    margin-left: 10px;
}

/* 主要内容区 */
.main-content {
    min-height: calc(100vh - 200px);
    padding: 40px 0;
}

/* 底部 */
.footer {
    background-color: #2c3e50;
    color: white;
    text-align: center;
    padding: 20px 0;
    margin-top: 60px;
}

/* 响应式 */
@media (max-width: 768px) {
    .navbar-content {
        flex-direction: column;
        gap: 15px;
    }
    
    .navbar-nav {
        flex-wrap: wrap;
        justify-content: center;
    }
    
    .container {
        padding: 0 15px;
    }
}