/* ========== 全局样式优化 ========== */
:root {
    --primary-color: #4a90e2;
    --primary-hover: #357abd;
    --secondary-color: #6c757d;
    --success-color: #28a745;
    --danger-color: #dc3545;
    --warning-color: #ffc107;
    --info-color: #17a2b8;
    --light-bg: #f8f9fa;
    --dark-bg: #212529;
    --border-color: #dee2e6;
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.15);
    --radius-md: 8px;
    --radius-lg: 12px;
    --transition: all 0.3s ease;
}

* {
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: var(--light-bg);
}

/* ========== 导航栏优化 ========== */
.navbar {
    background: linear-gradient(135deg, var(--primary-color) 0%, #357abd 100%) !important;
    box-shadow: var(--shadow-md);
    border-radius: 0 0 var(--radius-lg) var(--radius-lg);
    margin: 0 var(--radius-lg);
    max-width: 1400px;
    margin-left: auto;
    margin-right: auto;
}

.navbar-brand {
    font-weight: 700;
    font-size: 1.4rem !important;
    color: white !important;
    display: flex;
    align-items: center;
    gap: 10px;
}

.navbar-brand:hover {
    color: rgba(255, 255, 255, 0.9) !important;
}

.navbar-nav .nav-link {
    color: rgba(255, 255, 255, 0.9) !important;
    font-weight: 500;
    padding: 0.6rem 1rem !important;
    border-radius: var(--radius-md);
    margin: 0 0.2rem;
    transition: var(--transition);
}

.navbar-nav .nav-link:hover {
    background: rgba(255, 255, 255, 0.15);
    color: white !important;
}

.navbar-nav .nav-link.active {
    background: rgba(255, 255, 255, 0.2);
    color: white !important;
}

/* ========== 卡片优化 ========== */
.card {
    border: none;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    transition: var(--transition);
    margin-bottom: 1.5rem;
}

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

.card-header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-radius: var(--radius-lg) var(--radius-lg) 0 0 !important;
    font-weight: 600;
    padding: 1.2rem;
    border-bottom: none;
}

.card-body {
    padding: 1.5rem;
}

/* ========== 按钮优化 ========== */
.btn {
    border-radius: var(--radius-md);
    padding: 0.6rem 1.2rem;
    font-weight: 500;
    transition: var(--transition);
    border: none;
}

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

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

.btn-success {
    background: linear-gradient(135deg, var(--success-color) 0%, #218838 100%);
}

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

.btn-danger {
    background: linear-gradient(135deg, var(--danger-color) 0%, #c82333 100%);
}

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

.btn-warning {
    background: linear-gradient(135deg, var(--warning-color) 0%, #e0a800 100%);
    color: #333;
}

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

/* ========== 表单优化 ========== */
.form-control {
    border-radius: var(--radius-md);
    border: 2px solid var(--border-color);
    padding: 0.8rem 1rem;
    transition: var(--transition);
}

.form-control:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 0.2rem rgba(74, 144, 226, 0.15);
}

.form-group label {
    font-weight: 600;
    color: #555;
    margin-bottom: 0.5rem;
}

/* ========== 表格优化 ========== */
.table {
    border-radius: var(--radius-md);
    overflow: hidden;
}

.table thead th {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    font-weight: 600;
    border: none;
    padding: 1rem;
}

.table tbody tr {
    transition: var(--transition);
}

.table tbody tr:hover {
    background-color: rgba(74, 144, 226, 0.05);
}

.table td {
    padding: 1rem;
    vertical-align: middle;
}

/* ========== 登录页优化 ========== */
.login-page {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    padding: 20px;
}

.login-card {
    width: 100%;
    max-width: 420px;
    background: white;
    border-radius: 24px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    padding: 3rem;
    animation: slideUp 0.5s ease-out;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.login-card h2 {
    color: #333;
    font-weight: 700;
    margin-bottom: 2rem;
    text-align: center;
}

.login-card .form-control {
    height: 50px;
    font-size: 1rem;
}

.login-card .btn {
    height: 50px;
    font-size: 1.1rem;
    font-weight: 600;
}

/* ========== 项目列表优化 ========== */
.project-card {
    background: white;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    padding: 1.5rem;
    margin-bottom: 1rem;
    transition: var(--transition);
    cursor: pointer;
}

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

.project-card.active {
    border: 3px solid var(--primary-color);
}

.project-title {
    font-size: 1.3rem;
    font-weight: 700;
    color: #333;
    margin-bottom: 0.5rem;
}

.project-type {
    display: inline-block;
    padding: 0.3rem 0.8rem;
    background: var(--primary-color);
    color: white;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.project-info {
    color: #666;
    font-size: 0.9rem;
}

.project-stats {
    display: flex;
    gap: 1.5rem;
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 1px solid var(--border-color);
}

.stat-item {
    text-align: center;
}

.stat-value {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
}

.stat-label {
    font-size: 0.85rem;
    color: #666;
}

/* ========== 标签优化 ========== */
.badge {
    padding: 0.4rem 0.8rem;
    border-radius: 20px;
    font-weight: 600;
    font-size: 0.85rem;
}

.badge-primary {
    background: var(--primary-color);
    color: white;
}

.badge-success {
    background: var(--success-color);
    color: white;
}

.badge-danger {
    background: var(--danger-color);
    color: white;
}

.badge-warning {
    background: var(--warning-color);
    color: #333;
}

/* ========== 分页优化 ========== */
.pagination {
    display: flex;
    justify-content: center;
    gap: 0.5rem;
    margin-top: 2rem;
}

.page-link {
    border: none;
    border-radius: var(--radius-md);
    padding: 0.6rem 1rem;
    color: var(--primary-color);
    font-weight: 500;
    transition: var(--transition);
}

.page-link:hover {
    background: rgba(74, 144, 226, 0.1);
}

.page-item.active .page-link {
    background: var(--primary-color);
    color: white;
}

/* ========== 模态框优化 ========== */
.modal-content {
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
}

.modal-header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-radius: var(--radius-lg) var(--radius-lg) 0 0;
    padding: 1.2rem;
}

.modal-title {
    font-weight: 600;
}

.modal-footer {
    border-top: 1px solid var(--border-color);
    padding: 1.2rem;
}

/* ========== 加载动画 ========== */
.spinner-wrapper {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(255, 255, 255, 0.9);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 9999;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 4px solid rgba(74, 144, 226, 0.2);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* ========== 通知消息优化 ========== */
.alert {
    border-radius: var(--radius-md);
    border: none;
    padding: 1rem 1.5rem;
    box-shadow: var(--shadow-md);
}

.alert-success {
    background: linear-gradient(135deg, var(--success-color) 0%, #218838 100%);
    color: white;
}

.alert-danger {
    background: linear-gradient(135deg, var(--danger-color) 0%, #c82333 100%);
    color: white;
}

.alert-warning {
    background: linear-gradient(135deg, var(--warning-color) 0%, #e0a800 100%);
    color: #333;
}

.alert-info {
    background: linear-gradient(135deg, var(--info-color) 0%, #138496 100%);
    color: white;
}

/* ========== 响应式设计 ========== */
@media (max-width: 768px) {
    .navbar {
        margin: 0;
        border-radius: 0;
    }
    
    .card {
        border-radius: var(--radius-md);
    }
    
    .login-card {
        padding: 2rem;
    }
    
    .table {
        font-size: 0.9rem;
    }
    
    .table thead th,
    .table td {
        padding: 0.75rem;
    }
    
    .project-stats {
        flex-direction: column;
        gap: 1rem;
    }
    
    .btn {
        padding: 0.5rem 1rem;
        font-size: 0.9rem;
    }
}

/* ========== 暗黑模式 ========== */
.dark-mode {
    --light-bg: #1a1a1a;
    --border-color: #333;
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.5);
}

.dark-mode body {
    background-color: var(--dark-bg);
    color: #e0e0e0;
}

.dark-mode .card {
    background: #2a2a2a;
    color: #e0e0e0;
}

.dark-mode .form-control {
    background: #2a2a2a;
    border-color: #444;
    color: #e0e0e0;
}

.dark-mode .table {
    background: #2a2a2a;
    color: #e0e0e0;
}

.dark-mode .table tbody tr:hover {
    background-color: rgba(102, 126, 234, 0.15);
}

.dark-mode .project-card {
    background: #2a2a2a;
    color: #e0e0e0;
}

.dark-mode .modal-content {
    background: #2a2a2a;
    color: #e0e0e0;
}

.dark-mode .login-card {
    background: #2a2a2a;
    color: #e0e0e0;
}

.dark-mode .login-card h2 {
    color: #e0e0e0;
}

/* ========== 动画效果 ========== */
.fade-in {
    animation: fadeIn 0.3s ease-in;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.slide-in {
    animation: slideIn 0.3s ease-out;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateX(-20px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

/* ========== 工具类 ========== */
.text-gradient {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

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