/* 全局样式 - 现代化项目管理系统 */
:root {
    --primary-color: #667eea;
    --primary-dark: #5a67d8;
    --secondary-color: #764ba2;
    --success-color: #48bb78;
    --warning-color: #ed8936;
    --error-color: #f56565;
    --info-color: #4299e1;
    
    --bg-color: #f7fafc;
    --bg-dark: #edf2f7;
    --card-bg: #ffffff;
    --text-primary: #2d3748;
    --text-secondary: #718096;
    --text-light: #a0aec0;
    --border-color: #e2e8f0;
    --border-light: #f0f4f8;
    
    --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    
    --radius-sm: 0.25rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    
    --transition: all 0.3s ease;
}

/* 基础重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-color);
}

/* 布局组件 */
.main-layout {
    display: flex;
    min-height: 100vh;
}

/* 侧边栏 */
.sidebar {
    width: 280px;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
    padding: 2rem 0;
    position: fixed;
    height: 100vh;
    overflow-y: auto;
    z-index: 1000;
    transition: transform 0.3s ease;
}

.sidebar-header {
    padding: 0 2rem 2rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    margin-bottom: 2rem;
}

.sidebar-header h1 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.sidebar-header p {
    opacity: 0.8;
    font-size: 0.875rem;
}

.sidebar-nav {
    padding: 0 1rem;
}

.nav-item {
    margin-bottom: 0.5rem;
}

.nav-link {
    display: flex;
    align-items: center;
    padding: 0.75rem 1rem;
    color: rgba(255, 255, 255, 0.9);
    text-decoration: none;
    border-radius: var(--radius-md);
    transition: var(--transition);
    font-weight: 500;
}

.nav-link:hover,
.nav-link.active {
    background: rgba(255, 255, 255, 0.1);
    color: white;
    transform: translateX(4px);
}

.nav-link i {
    width: 20px;
    margin-right: 0.75rem;
    text-align: center;
}

/* 主内容区 */
.content {
    flex: 1;
    margin-left: 280px;
    padding: 2rem;
    transition: margin-left 0.3s ease;
}

.content-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 2px solid var(--border-light);
}

.content-title {
    font-size: 2rem;
    font-weight: 700;
    color: var(--text-primary);
}

.content-subtitle {
    color: var(--text-secondary);
    margin-top: 0.25rem;
}

/* 卡片组件 */
.card {
    background: var(--card-bg);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
    overflow: hidden;
    transition: var(--transition);
}

.card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.card-header {
    padding: 1.5rem;
    border-bottom: 1px solid var(--border-color);
    background: linear-gradient(135deg, #f8fafc 0%, #e2e8f0 100%);
}

.card-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
}

.card-body {
    padding: 1.5rem;
}

/* 按钮组件 */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.5rem;
    font-size: 0.875rem;
    font-weight: 600;
    text-decoration: none;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition);
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    color: white;
}

.btn-secondary {
    background: var(--card-bg);
    color: var(--text-primary);
    border: 2px solid var(--border-color);
}

.btn-sm {
    padding: 0.5rem 1rem;
    font-size: 0.75rem;
}

/* 表单组件 */
.form-group {
    margin-bottom: 1.5rem;
}

.form-label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--text-primary);
}

.form-control {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 1rem;
    transition: var(--transition);
    background: var(--card-bg);
}

.form-control:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

/* 状态标签 */
.badge {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    border-radius: var(--radius-xl);
    letter-spacing: 0.025em;
}

.badge-primary { background: var(--primary-color); color: white; }
.badge-success { background: var(--success-color); color: white; }
.badge-warning { background: var(--warning-color); color: white; }
.badge-error { background: var(--error-color); color: white; }
.badge-info { background: var(--info-color); color: white; }

/* 统计卡片 */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: linear-gradient(135deg, var(--card-bg) 0%, #f8fafc 100%);
    padding: 2rem;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    border-left: 4px solid var(--primary-color);
    transition: var(--transition);
}

.stat-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.stat-number {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.stat-label {
    color: var(--text-secondary);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.025em;
    font-size: 0.875rem;
}

/* 动画效果 */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.fade-in {
    animation: fadeIn 0.6s ease-out;
}

/* 响应式设计 */
@media (max-width: 1024px) {
    .sidebar {
        transform: translateX(-100%);
    }
    
    .sidebar.open {
        transform: translateX(0);
    }
    
    .content {
        margin-left: 0;
    }
}

@media (max-width: 768px) {
    .content {
        padding: 1rem;
    }
    
    .content-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
}

/* 移动端菜单按钮 */
.mobile-menu-btn {
    display: none;
    position: fixed;
    top: 1rem;
    left: 1rem;
    z-index: 1001;
    background: var(--primary-color);
    color: white;
    border: none;
    padding: 0.75rem;
    border-radius: var(--radius-md);
    cursor: pointer;
    box-shadow: var(--shadow-md);
}

@media (max-width: 1024px) {
    .mobile-menu-btn {
        display: block;
    }
}

/* 遮罩层 */
.overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 999;
}

.overlay.active {
    display: block;
}

/* 提示信息 */
.alert {
    padding: 1rem;
    border-radius: var(--radius-md);
    margin-bottom: 1rem;
    border-left: 4px solid;
}

.alert-success {
    background: #f0fff4;
    border-color: var(--success-color);
    color: #22543d;
}

.alert-error {
    background: #fed7d7;
    border-color: var(--error-color);
    color: #742a2a;
}