/* ========================================
   客户到期提醒管理系统 - 后台样式
   清爽简洁、响应式中文后台
   ======================================== */

:root {
    --primary: #4f46e5;
    --primary-dark: #4338ca;
    --primary-light: #e0e7ff;
    --secondary: #64748b;
    --success: #22c55e;
    --warning: #f59e0b;
    --danger: #ef4444;
    --info: #3b82f6;
    --dark: #1e293b;
    --gray: #94a3b8;
    --gray-light: #f1f5f9;
    --gray-border: #e2e8f0;
    --white: #ffffff;
    --sidebar-width: 240px;
    --sidebar-collapsed: 60px;
    --header-height: 60px;
    --radius: 8px;
    --shadow: 0 1px 3px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 25px rgba(0,0,0,0.1);
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    font-size: 14px;
    color: var(--dark);
    background: #f8fafc;
    line-height: 1.6;
}

/* ===== 布局 ===== */
.admin-wrapper {
    display: flex;
    min-height: 100vh;
}

.sidebar {
    width: var(--sidebar-width);
    background: var(--white);
    border-right: 1px solid var(--gray-border);
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    z-index: 1000;
    transition: width 0.3s;
    overflow-y: auto;
    overflow-x: hidden;
}

.sidebar.collapsed {
    width: var(--sidebar-collapsed);
}

.sidebar.collapsed .logo span,
.sidebar.collapsed .nav-item span {
    display: none;
}

.sidebar-header {
    height: var(--header-height);
    display: flex;
    align-items: center;
    padding: 0 20px;
    border-bottom: 1px solid var(--gray-border);
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 16px;
    font-weight: 700;
    color: var(--primary);
    white-space: nowrap;
}

.logo i {
    font-size: 22px;
    min-width: 24px;
    text-align: center;
}

.sidebar-nav {
    padding: 15px 10px;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 15px;
    border-radius: var(--radius);
    color: var(--secondary);
    text-decoration: none;
    margin-bottom: 4px;
    transition: all 0.2s;
    white-space: nowrap;
}

.nav-item i {
    font-size: 16px;
    width: 20px;
    text-align: center;
}

.nav-item:hover {
    background: var(--gray-light);
    color: var(--primary);
}

.nav-item.active {
    background: var(--primary-light);
    color: var(--primary);
    font-weight: 600;
}

.main-content {
    flex: 1;
    margin-left: var(--sidebar-width);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    transition: margin-left 0.3s;
}

.main-content.expanded {
    margin-left: var(--sidebar-collapsed);
}

.top-header {
    height: var(--header-height);
    background: var(--white);
    border-bottom: 1px solid var(--gray-border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 25px;
    position: sticky;
    top: 0;
    z-index: 100;
}

.menu-toggle {
    background: none;
    border: none;
    font-size: 18px;
    color: var(--secondary);
    cursor: pointer;
    padding: 5px;
}

.header-right {
    display: flex;
    align-items: center;
    gap: 20px;
}

.admin-name {
    color: var(--secondary);
    font-size: 14px;
}

.admin-name i {
    margin-right: 5px;
    color: var(--primary);
}

.logout-btn {
    color: var(--danger);
    text-decoration: none;
    font-size: 14px;
    display: flex;
    align-items: center;
    gap: 5px;
    transition: opacity 0.2s;
}

.logout-btn:hover { opacity: 0.7; }

.page-container {
    flex: 1;
    padding: 25px;
}

.admin-footer {
    background: var(--white);
    border-top: 1px solid var(--gray-border);
    padding: 15px 25px;
    text-align: center;
    color: var(--gray);
    font-size: 12px;
}

/* ===== 页面标题 ===== */
.page-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 25px;
    flex-wrap: wrap;
    gap: 15px;
}

.page-title {
    font-size: 22px;
    font-weight: 700;
    color: var(--dark);
}

.page-actions {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

/* ===== 统计卡片 ===== */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 20px;
    margin-bottom: 25px;
}

.stat-card {
    background: var(--white);
    border-radius: var(--radius);
    padding: 20px;
    box-shadow: var(--shadow);
    display: flex;
    align-items: center;
    gap: 15px;
    transition: transform 0.2s;
}

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

.stat-icon {
    width: 50px;
    height: 50px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    flex-shrink: 0;
}

.stat-icon.blue { background: #eff6ff; color: var(--info); }
.stat-icon.green { background: #f0fdf4; color: var(--success); }
.stat-icon.orange { background: #fff7ed; color: var(--warning); }
.stat-icon.red { background: #fef2f2; color: var(--danger); }
.stat-icon.purple { background: #faf5ff; color: #a855f7; }
.stat-icon.gray { background: #f8fafc; color: var(--gray); }

.stat-info h3 {
    font-size: 24px;
    font-weight: 700;
    color: var(--dark);
    line-height: 1;
    margin-bottom: 5px;
}

.stat-info p {
    font-size: 13px;
    color: var(--gray);
}

/* ===== 面板卡片 ===== */
.card {
    background: var(--white);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    margin-bottom: 20px;
}

.card-header {
    padding: 18px 20px;
    border-bottom: 1px solid var(--gray-border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 10px;
}

.card-title {
    font-size: 16px;
    font-weight: 600;
    color: var(--dark);
    display: flex;
    align-items: center;
    gap: 8px;
}

.card-body {
    padding: 20px;
}

/* ===== 表格 ===== */
.table-responsive {
    overflow-x: auto;
}

.data-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 13px;
}

.data-table th {
    background: var(--gray-light);
    color: var(--secondary);
    font-weight: 600;
    text-align: left;
    padding: 12px 15px;
    border-bottom: 2px solid var(--gray-border);
    white-space: nowrap;
}

.data-table td {
    padding: 12px 15px;
    border-bottom: 1px solid var(--gray-border);
    vertical-align: middle;
}

.data-table tbody tr:hover {
    background: #fafafa;
}

.data-table tbody tr:last-child td {
    border-bottom: none;
}

/* ===== 标签 ===== */
.badge {
    display: inline-flex;
    align-items: center;
    padding: 4px 10px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 500;
}

.badge-success { background: #dcfce7; color: #166534; }
.badge-warning { background: #fef3c7; color: #92400e; }
.badge-orange { background: #ffedd5; color: #9a3412; }
.badge-danger { background: #fee2e2; color: #991b1b; }
.badge-info { background: #dbeafe; color: #1e40af; }
.badge-gray { background: #f1f5f9; color: #64748b; }

/* ===== 按钮 ===== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 8px 16px;
    border-radius: var(--radius);
    font-size: 13px;
    font-weight: 500;
    cursor: pointer;
    border: none;
    text-decoration: none;
    transition: all 0.2s;
    white-space: nowrap;
}

.btn:hover { opacity: 0.9; transform: translateY(-1px); }

.btn-primary { background: var(--primary); color: #fff; }
.btn-success { background: var(--success); color: #fff; }
.btn-warning { background: var(--warning); color: #fff; }
.btn-danger { background: var(--danger); color: #fff; }
.btn-secondary { background: var(--gray-light); color: var(--secondary); border: 1px solid var(--gray-border); }
.btn-info { background: var(--info); color: #fff; }

.btn-sm { padding: 5px 12px; font-size: 12px; }
.btn-lg { padding: 10px 24px; font-size: 15px; }

/* ===== 表单 ===== */
.form-group {
    margin-bottom: 18px;
}

.form-label {
    display: block;
    margin-bottom: 6px;
    font-size: 13px;
    font-weight: 500;
    color: var(--dark);
}

.form-label .required {
    color: var(--danger);
    margin-left: 2px;
}

.form-control {
    width: 100%;
    padding: 9px 12px;
    border: 1px solid var(--gray-border);
    border-radius: var(--radius);
    font-size: 14px;
    color: var(--dark);
    background: var(--white);
    transition: border-color 0.2s, box-shadow 0.2s;
}

.form-control:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-light);
}

.form-control::placeholder {
    color: var(--gray);
}

select.form-control {
    cursor: pointer;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%2394a3b8' d='M6 8L1 3h10z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 12px center;
    padding-right: 32px;
}

textarea.form-control {
    min-height: 100px;
    resize: vertical;
}

.form-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 0 20px;
}

.form-hint {
    font-size: 12px;
    color: var(--gray);
    margin-top: 4px;
}

/* ===== 搜索筛选区 ===== */
.filter-bar {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
    margin-bottom: 20px;
    padding: 15px;
    background: var(--gray-light);
    border-radius: var(--radius);
}

.filter-bar .form-control {
    width: auto;
    min-width: 150px;
}

/* ===== 分页 ===== */
.pagination {
    display: flex;
    align-items: center;
    gap: 5px;
    margin-top: 20px;
    justify-content: center;
    flex-wrap: wrap;
}

.page-item {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 32px;
    height: 32px;
    padding: 0 10px;
    border-radius: 6px;
    font-size: 13px;
    text-decoration: none;
    color: var(--dark);
    background: var(--white);
    border: 1px solid var(--gray-border);
    transition: all 0.2s;
    cursor: pointer;
}

.page-item:hover {
    border-color: var(--primary);
    color: var(--primary);
}

.page-item.active {
    background: var(--primary);
    color: #fff;
    border-color: var(--primary);
}

.page-item.disabled {
    color: var(--gray);
    cursor: not-allowed;
}

.page-info {
    font-size: 13px;
    color: var(--gray);
    margin-left: 10px;
}

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

.login-box {
    background: var(--white);
    border-radius: 16px;
    padding: 40px;
    width: 100%;
    max-width: 420px;
    box-shadow: var(--shadow-lg);
}

.login-logo {
    text-align: center;
    margin-bottom: 30px;
}

.login-logo i {
    font-size: 48px;
    color: var(--primary);
    margin-bottom: 15px;
}

.login-logo h2 {
    font-size: 22px;
    color: var(--dark);
    margin-bottom: 5px;
}

.login-logo p {
    font-size: 13px;
    color: var(--gray);
}

.login-form .btn {
    width: 100%;
    padding: 12px;
    font-size: 15px;
}

/* ===== 弹窗模态框 ===== */
.modal-overlay {
    display: none;
    position: fixed;
    top: 0; left: 0; right: 0; bottom: 0;
    background: rgba(0,0,0,0.5);
    z-index: 2000;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.modal-overlay.active {
    display: flex;
}

.modal-box {
    background: var(--white);
    border-radius: 12px;
    width: 100%;
    max-width: 550px;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: var(--shadow-lg);
    animation: modalSlideIn 0.3s ease;
}

.modal-box.modal-lg {
    max-width: 800px;
}

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

.modal-header {
    padding: 18px 24px;
    border-bottom: 1px solid var(--gray-border);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.modal-header h3 {
    font-size: 17px;
    font-weight: 600;
}

.modal-close {
    background: none;
    border: none;
    font-size: 20px;
    color: var(--gray);
    cursor: pointer;
}

.modal-body {
    padding: 24px;
}

.modal-footer {
    padding: 15px 24px;
    border-top: 1px solid var(--gray-border);
    display: flex;
    justify-content: flex-end;
    gap: 10px;
}

/* ===== 消息提示 ===== */
.toast-container {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 9999;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.toast {
    padding: 12px 20px;
    border-radius: var(--radius);
    color: #fff;
    font-size: 14px;
    box-shadow: var(--shadow-lg);
    animation: toastSlideIn 0.3s ease;
    display: flex;
    align-items: center;
    gap: 10px;
    max-width: 350px;
}

.toast.success { background: var(--success); }
.toast.error { background: var(--danger); }
.toast.warning { background: var(--warning); }
.toast.info { background: var(--info); }

@keyframes toastSlideIn {
    from { opacity: 0; transform: translateX(100%); }
    to { opacity: 1; transform: translateX(0); }
}

/* ===== Tab标签页 ===== */
.tab-nav {
    display: flex;
    gap: 0;
    border-bottom: 2px solid var(--gray-border);
    margin-bottom: 20px;
}

.tab-nav a {
    padding: 10px 20px;
    color: var(--secondary);
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;
    border-bottom: 2px solid transparent;
    margin-bottom: -2px;
    transition: all 0.2s;
}

.tab-nav a:hover {
    color: var(--primary);
}

.tab-nav a.active {
    color: var(--primary);
    border-bottom-color: var(--primary);
}

/* ===== 空状态 ===== */
.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: var(--gray);
}

.empty-state i {
    font-size: 48px;
    margin-bottom: 15px;
    opacity: 0.5;
}

.empty-state h4 {
    font-size: 16px;
    margin-bottom: 8px;
    color: var(--secondary);
}

/* ===== 快捷操作按钮组 ===== */
.action-btns {
    display: flex;
    gap: 6px;
}

.action-btns .btn {
    padding: 5px 10px;
    font-size: 12px;
}

/* ===== 复选框样式 ===== */
.custom-checkbox {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    cursor: pointer;
    font-size: 14px;
}

.custom-checkbox input[type="checkbox"] {
    width: 16px;
    height: 16px;
    accent-color: var(--primary);
    cursor: pointer;
}

/* ===== 响应式 ===== */
@media (max-width: 768px) {
    .sidebar {
        transform: translateX(-100%);
    }
    .sidebar.show {
        transform: translateX(0);
    }
    .main-content {
        margin-left: 0;
    }
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .filter-bar {
        flex-direction: column;
    }
    .filter-bar .form-control {
        width: 100%;
    }
    .page-header {
        flex-direction: column;
        align-items: flex-start;
    }
    .data-table {
        font-size: 12px;
    }
    .data-table th,
    .data-table td {
        padding: 8px 10px;
    }
}

/* ===== 滚动条美化 ===== */
::-webkit-scrollbar {
    width: 6px;
    height: 6px;
}

::-webkit-scrollbar-track {
    background: var(--gray-light);
}

::-webkit-scrollbar-thumb {
    background: var(--gray-border);
    border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--gray);
}