/* ========================================
   App Layout - 应用主布局
   ======================================== */
.app {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

.app.login-mode {
    display: flex;
    align-items: center;
    justify-content: center;
}

/* ========================================
   Top Header - 顶部导航
   ======================================== */
.top-header {
    height: var(--header-height);
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 var(--spacing-xl);
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow-sm);
}

.header-left {
    display: flex;
    align-items: center;
}

.header-brand {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.header-logo {
    width: 40px;
    height: 40px;
    background: var(--primary-gradient);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-white);
    font-size: 20px;
}

.header-brand-text h1 {
    font-size: var(--font-size-lg);
    font-weight: 700;
    color: var(--text-primary);
    line-height: 1.2;
    margin: 0;
}

.header-brand-text p {
    font-size: var(--font-size-xs);
    color: var(--text-muted);
    margin: 0;
}

.header-right {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.header-action {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-md);
    color: var(--text-secondary);
    transition: all var(--transition-fast);
    cursor: pointer;
    background: none;
    border: none;
    font-size: 16px;
}

.header-action:hover {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

/* ========================================
   Login Button (未登录状态)
   ======================================== */
.header-login-btn {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: 8px 20px;
    background: var(--primary-gradient);
    color: var(--text-white);
    border: none;
    border-radius: var(--radius-full);
    font-size: var(--font-size-sm);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.header-login-btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}

.header-login-btn i {
    font-size: 14px;
}

/* ========================================
   User Menu (已登录状态)
   ======================================== */
.header-user-menu {
    position: relative;
}

.header-user-avatar {
    cursor: pointer;
    padding: 4px;
    border-radius: 50%;
    transition: all var(--transition-fast);
}

.header-user-avatar:hover {
    background: var(--bg-tertiary);
}

.user-dropdown {
    position: absolute;
    top: calc(100% + 12px);
    right: 0;
    width: 240px;
    background: var(--bg-primary);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    border: 1px solid var(--border-color);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px) scale(0.95);
    transition: all var(--transition-fast);
    z-index: 1000;
}

.user-dropdown::before {
    content: "";
    position: absolute;
    top: -6px;
    right: 16px;
    width: 12px;
    height: 12px;
    background: var(--bg-primary);
    border-top: 1px solid var(--border-color);
    border-left: 1px solid var(--border-color);
    transform: rotate(45deg);
}

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

.dropdown-user-info {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-lg);
}

.avatar-lg {
    width: 44px;
    height: 44px;
    font-size: var(--font-size-lg);
}

.dropdown-user-details {
    flex: 1;
    min-width: 0;
}

.dropdown-username {
    font-size: var(--font-size-md);
    font-weight: 600;
    color: var(--text-primary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.dropdown-user-email {
    font-size: var(--font-size-xs);
    color: var(--text-muted);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.dropdown-divider {
    height: 1px;
    background: var(--border-color);
    margin: 0 var(--spacing-md);
}

.dropdown-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    width: 100%;
    padding: var(--spacing-md) var(--spacing-lg);
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    background: none;
    border: none;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.dropdown-item:hover {
    background: var(--bg-secondary);
    color: var(--text-primary);
}

.dropdown-item.logout:hover {
    background: rgba(239, 68, 68, 0.1);
    color: var(--danger-color);
}

.dropdown-item i {
    width: 18px;
    text-align: center;
}

/* ========================================
   Confirm Dialog - 确认弹窗
   ======================================== */
.confirm-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 10000;
    opacity: 0;
    transition: opacity var(--transition-normal);
    backdrop-filter: blur(4px);
}

.confirm-overlay.show {
    opacity: 1;
}

.confirm-dialog {
    background: var(--bg-primary);
    border-radius: var(--radius-xl);
    padding: var(--spacing-2xl);
    text-align: center;
    max-width: 320px;
    width: 90%;
    box-shadow: var(--shadow-xl);
    transform: scale(0.9);
    transition: transform var(--transition-normal);
}

.confirm-overlay.show .confirm-dialog {
    transform: scale(1);
}

.confirm-icon {
    width: 56px;
    height: 56px;
    background: rgba(239, 68, 68, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto var(--spacing-lg);
    font-size: 24px;
    color: var(--danger-color);
}

.confirm-dialog h3 {
    font-size: var(--font-size-xl);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

.confirm-dialog p {
    font-size: var(--font-size-sm);
    color: var(--text-muted);
    margin-bottom: var(--spacing-xl);
}

.confirm-actions {
    display: flex;
    gap: var(--spacing-md);
}

.confirm-actions .btn {
    flex: 1;
}

/* ========================================
   Main Content - 主内容区
   ======================================== */
.main-content {
    flex: 1;
    min-height: calc(100vh - var(--header-height) - 64px);
}

/* ========================================
   Page Content - 页面内容
   ======================================== */
.page-content {
    padding: var(--spacing-xl);
}

/* ========================================
   Tab Bar - 底部标签栏
   ======================================== */
.tab-bar {
    position: fixed;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 64px;
    background: var(--bg-primary);
    border-top: 1px solid var(--border-color);
    z-index: 1000;
    padding: 0 var(--spacing-sm);
    box-shadow: 0 -4px 12px rgba(0, 0, 0, 0.05);
}

.tab-bar-inner {
    display: flex;
    align-items: center;
    justify-content: space-around;
    height: 100%;
    width: 100%;
    max-width: 600px;
    margin: 0 auto;
}

.tab-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 4px;
    padding: var(--spacing-sm) var(--spacing-2xl);
    color: var(--text-muted);
    transition: all var(--transition-fast);
    cursor: pointer;
    border: none;
    background: none;
    border-radius: var(--radius-md);
    flex: 1;
    position: relative;
}

.tab-item:hover {
    color: var(--text-secondary);
}

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

.tab-item-icon {
    font-size: 22px;
    line-height: 1;
}

.tab-item-text {
    font-size: 12px;
    font-weight: 600;
    white-space: nowrap;
}

/* ========================================
   Stats Card - 统计卡片
   ======================================== */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.stat-card {
    background: var(--bg-primary);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-md);
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
    transition: all var(--transition-normal);
}

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

.stat-icon {
    width: 56px;
    height: 56px;
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    flex-shrink: 0;
}

.stat-icon-primary {
    background: rgba(99, 102, 241, 0.1);
    color: var(--primary-color);
}

.stat-icon-warning {
    background: rgba(245, 158, 11, 0.1);
    color: var(--warning-color);
}

.stat-icon-success {
    background: rgba(16, 185, 129, 0.1);
    color: var(--success-color);
}

.stat-icon-danger {
    background: rgba(239, 68, 68, 0.1);
    color: var(--danger-color);
}

.stat-icon-info {
    background: rgba(6, 182, 212, 0.1);
    color: var(--info-color);
}

.stat-info h3 {
    font-size: var(--font-size-3xl);
    font-weight: 700;
    color: var(--text-primary);
    line-height: 1;
    margin-bottom: 4px;
}

.stat-info p {
    font-size: var(--font-size-sm);
    color: var(--text-muted);
    margin: 0;
}

/* ========================================
   Avatar - 头像
   ======================================== */
.avatar {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    background: var(--primary-gradient);
    color: var(--text-white);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: var(--font-size-sm);
    flex-shrink: 0;
}

/* ========================================
   Responsive - 响应式
   ======================================== */
@media (max-width: 768px) {
    .top-header {
        padding: 0 var(--spacing-md);
    }
    
    .page-content {
        padding: var(--spacing-md);
        padding-bottom: 80px;
    }
    
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-md);
    }
    
    .stat-card {
        padding: var(--spacing-md);
    }
    
    .stat-icon {
        width: 44px;
        height: 44px;
        font-size: 20px;
    }
    
    .stat-info h3 {
        font-size: var(--font-size-2xl);
    }
}

@media (max-width: 480px) {
    .header-brand-text p {
        display: none;
    }
}