/* ===== 变量 ===== */
:root {
    --primary: #2563eb;
    --primary-light: #3b82f6;
    --primary-dark: #1d4ed8;
    --success: #16a34a;
    --danger: #dc2626;
    --warning: #d97706;
    --info: #0891b2;
    --bg: #f1f5f9;
    --bg-gradient: linear-gradient(135deg, #f0f4ff 0%, #f1f5f9 50%, #fef2f2 100%);
    --card-bg: rgba(255,255,255,0.75);
    --card-border: rgba(255,255,255,0.3);
    --border: #e2e8f0;
    --text: #1e293b;
    --text-secondary: #64748b;
    --radius: 8px;
    --radius-lg: 12px;
    --shadow: 0 1px 3px rgba(0,0,0,0.06);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.08);
    --shadow-lg: 0 10px 30px rgba(0,0,0,0.1);
    --glass-blur: 12px;
    --glass-bg: rgba(255,255,255,0.7);
    --glass-border: rgba(255,255,255,0.4);
    --glass-shadow: 0 4px 20px rgba(0,0,0,0.06);
    --nav-height: 56px;
    --container-padding: 16px;
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-fast: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
}
@media (min-width: 768px) {
    :root { --container-padding: 24px; }
}

/* ===== 重置 ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Noto Sans SC", sans-serif;
    background: var(--bg-gradient);
    background-attachment: fixed;
    color: var(--text);
    line-height: 1.6;
    min-height: 100vh;
    font-size: 16px;
}
a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ===== 布局 ===== */
.container {
    max-width: 960px;
    margin: 0 auto;
    padding: 0 var(--container-padding);
}
.page-content { padding: var(--spacing-md) 0 40px; animation: contentFadeIn 0.4s cubic-bezier(0.4, 0, 0.2, 1); }
@media (min-width: 768px) { .page-content { padding: 24px 0 48px; } }
@keyframes contentFadeIn {
    from { opacity: 0; transform: translateY(8px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ===== 导航栏 ===== */
.nav {
    background: rgba(37,99,235,0.92);
    backdrop-filter: blur(var(--glass-blur));
    -webkit-backdrop-filter: blur(var(--glass-blur));
    color: #fff;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 2px 20px rgba(37,99,235,0.15);
}
.nav-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: var(--nav-height);
    gap: var(--spacing-sm);
}
.nav-brand {
    font-size: 1.05rem;
    font-weight: 600;
    color: #fff;
    white-space: nowrap;
    flex-shrink: 0;
}
.nav-brand:hover { text-decoration: none; }

/* 导航链接 - 桌面 */
.nav-links {
    display: flex;
    gap: 2px;
    align-items: center;
    flex-wrap: wrap;
}
.nav-links a {
    color: rgba(255,255,255,0.85);
    padding: 6px 10px;
    border-radius: 6px;
    font-size: 0.88rem;
    transition: background var(--transition);
    white-space: nowrap;
}
.nav-links a:hover, .nav-links a.active {
    background: rgba(255,255,255,0.15);
    color: #fff;
    text-decoration: none;
}
.nav-user {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 0.85rem;
    flex-shrink: 0;
    white-space: nowrap;
}
.nav-user span { opacity: 0.85; }
.nav-user-link { color: #fff !important; }

/* 汉堡按钮 */
.hamburger {
    display: none;
    background: none;
    border: none;
    color: #fff;
    font-size: 1.6rem;
    cursor: pointer;
    padding: 4px 8px;
    line-height: 1;
    border-radius: 6px;
    transition: background var(--transition);
    z-index: 101;
}
.hamburger:hover { background: rgba(255,255,255,0.15); }
.hamburger.open { background: rgba(255,255,255,0.1); }

/* 导航链接的过渡容器 */
.nav-links-wrap {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    flex: 1;
    justify-content: flex-end;
}

/* ===== 卡片 ===== */
.card {
    background: var(--glass-bg);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    border: 1px solid var(--card-border);
    border-radius: var(--radius-lg);
    box-shadow: var(--glass-shadow);
    padding: var(--spacing-md);
    margin-bottom: var(--spacing-md);
    transition: all var(--transition);
}
@media (min-width: 768px) { .card { padding: 20px; margin-bottom: 20px; } }
.card:hover { box-shadow: var(--shadow-md); transform: translateY(-1px); }
.card-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--spacing-md);
    flex-wrap: wrap;
    gap: var(--spacing-sm);
}
.card-title { font-size: 1.1rem; font-weight: 600; }

/* ===== 按钮 ===== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 4px;
    padding: 9px 16px;
    border: none;
    border-radius: 8px;
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition);
    line-height: 1.4;
    text-decoration: none;
    min-height: 38px;
    user-select: none;
    -webkit-tap-highlight-color: transparent;
    position: relative;
    overflow: hidden;
}
.btn::after {
    content: '';
    position: absolute;
    inset: 0;
    background: rgba(255,255,255,0);
    transition: background var(--transition);
}
.btn:hover { text-decoration: none; opacity: 1; transform: translateY(-2px); box-shadow: 0 4px 12px rgba(0,0,0,0.15); }
.btn:hover::after { background: rgba(255,255,255,0.1); }
.btn:active { transform: translateY(0); box-shadow: none; }
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); }
.btn-success { background: var(--success); color: #fff; }
.btn-danger { background: var(--danger); color: #fff; }
.btn-warning { background: var(--warning); color: #fff; }
.btn-secondary { background: rgba(226,232,240,0.8); color: var(--text); backdrop-filter: blur(4px); -webkit-backdrop-filter: blur(4px); border: 1px solid rgba(255,255,255,0.3); }
.btn-secondary:hover { background: #cbd5e1; }
.btn-sm { padding: 5px 10px; font-size: 0.8rem; min-height: 30px; }
.btn-block { width: 100%; justify-content: center; }

/* ===== 表单 ===== */
.form-group { margin-bottom: var(--spacing-md); }
.form-label { display: block; margin-bottom: 4px; font-weight: 500; font-size: 0.9rem; color: var(--text-secondary); }
.form-input, .form-select, .form-textarea {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--border);
    border-radius: 8px;
    font-size: 0.95rem;
    background: rgba(255,255,255,0.8);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    color: var(--text);
    transition: all var(--transition);
    min-height: 42px;
}
.form-input:focus, .form-select:focus, .form-textarea:focus {
    outline: none;
    border-color: var(--primary);
    background: rgba(255,255,255,0.95);
    box-shadow: 0 0 0 3px rgba(37,99,235,0.12), 0 2px 8px rgba(37,99,235,0.08);
}
.form-textarea { resize: vertical; min-height: 80px; }
.form-row { display: grid; grid-template-columns: 1fr; gap: var(--spacing-sm); }
@media (min-width: 480px) { .form-row { grid-template-columns: 1fr 1fr; gap: 12px; } }
.form-hint { font-size: 0.8rem; color: var(--text-secondary); margin-top: 2px; }

/* ===== 表格 ===== */
.table-wrap { overflow-x: auto; -webkit-overflow-scrolling: touch; margin: 0 calc(-1 * var(--container-padding)); padding: 0 var(--container-padding); }
@media (min-width: 768px) { .table-wrap { margin: 0; padding: 0; } }
.table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.875rem;
}
.table th, .table td {
    padding: 10px 12px;
    text-align: left;
    border-bottom: 1px solid var(--border);
    white-space: nowrap;
}
.table th { background: #f8fafc; font-weight: 600; color: var(--text-secondary); font-size: 0.8rem; }
.table tr:hover td { background: #f8fafc; }
.table .actions { display: flex; gap: 6px; flex-wrap: wrap; }

/* ===== 徽章 ===== */
.badge {
    display: inline-block;
    padding: 3px 10px;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 500;
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    border: 1px solid rgba(255,255,255,0.3);
}
.badge-success { background: #dcfce7; color: var(--success); }
.badge-danger { background: #fee2e2; color: var(--danger); }
.badge-warning { background: #fef3c7; color: var(--warning); }
.badge-info { background: #cffafe; color: var(--info); }
.badge-primary { background: #dbeafe; color: var(--primary); }

/* ===== 提示 ===== */
.alert {
    padding: 12px 16px;
    border-radius: var(--radius-lg);
    margin-bottom: var(--spacing-md);
    font-size: 0.9rem;
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
}
.alert-success { background: rgba(220,252,231,0.85); color: #166534; border: 1px solid rgba(187,247,208,0.5); }
.alert-danger { background: rgba(254,226,226,0.85); color: #991b1b; border: 1px solid rgba(254,202,202,0.5); }
.alert-warning { background: rgba(254,243,199,0.85); color: #92400e; border: 1px solid rgba(253,230,138,0.5); }
.alert-info { background: rgba(207,250,254,0.85); color: #155e75; border: 1px solid rgba(165,243,252,0.5); }

/* ===== Toast ===== */
.toast-container {
    position: fixed;
    top: 70px;
    right: var(--spacing-md);
    z-index: 1000;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}
.toast {
    padding: 12px 20px;
    border-radius: var(--radius-lg);
    color: #fff;
    font-size: 0.9rem;
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    box-shadow: 0 4px 20px rgba(0,0,0,0.2);
    animation: slideIn 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    max-width: 320px;
    border: 1px solid rgba(255,255,255,0.15);
}
.toast-success { background: var(--success); }
.toast-error { background: var(--danger); }
.toast-info { background: var(--info); }
@keyframes slideIn {
    from { transform: translateX(100%); opacity: 0; }
    to { transform: translateX(0); opacity: 1; }
}
/* 移动端 Toast 全宽 */
@media (max-width: 480px) {
    .toast-container {
        left: var(--spacing-md);
        right: var(--spacing-md);
    }
    .toast {
        max-width: 100%;
        text-align: center;
    }
}

/* ===== 模态框 ===== */
.modal-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.35);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    z-index: 200;
    align-items: flex-end;
    justify-content: center;
    padding: 0;
}
@media (min-width: 480px) {
    .modal-overlay { align-items: center; padding: var(--spacing-md); }
}
.modal-overlay.active { display: flex; }
.modal {
    background: var(--glass-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--card-border);
    border-radius: var(--radius-lg) var(--radius-lg) 0 0;
    box-shadow: 0 -4px 30px rgba(0,0,0,0.1);
    max-width: 100%;
    width: 100%;
    max-height: 85vh;
    overflow-y: auto;
    padding: var(--spacing-lg) var(--spacing-md);
    animation: slideUp 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}
@media (min-width: 480px) {
    .modal {
        border-radius: var(--radius-lg);
        max-width: 480px;
        padding: var(--spacing-lg);
        animation: fadeIn 0.25s ease;
    }
}
@keyframes slideUp {
    from { transform: translateY(100%); }
    to { transform: translateY(0); }
}
@keyframes fadeIn {
    from { opacity: 0; transform: scale(0.95); }
    to { opacity: 1; transform: scale(1); }
}
.modal-title { font-size: 1.1rem; font-weight: 600; margin-bottom: var(--spacing-md); }
.modal-actions { display: flex; gap: var(--spacing-sm); justify-content: flex-end; margin-top: 20px; }
@media (max-width: 480px) {
    .modal-actions .btn { flex: 1; }
}

/* ===== 考勤日历 ===== */
.calendar-controls {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--spacing-md);
    flex-wrap: wrap;
    gap: var(--spacing-sm);
}
.calendar-nav { display: flex; align-items: center; gap: var(--spacing-sm); }
.calendar-nav .month-label { font-size: 1rem; font-weight: 600; min-width: 120px; text-align: center; }
.calendar-table-wrap {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    border: 1px solid var(--card-border);
    border-radius: var(--radius-lg);
    background: var(--glass-bg);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
}
.calendar-table {
    border-collapse: collapse;
    font-size: 0.8rem;
    min-width: 600px;
    width: 100%;
}
.calendar-table th, .calendar-table td {
    padding: 6px 4px;
    text-align: center;
    border: 1px solid var(--border);
    min-width: 36px;
}
.calendar-table th { background: #f1f5f9; font-weight: 600; position: sticky; top: 0; z-index: 1; }
.calendar-table .student-name { text-align: left; font-weight: 500; white-space: nowrap; position: sticky; left: 0; background: #fff; z-index: 2; min-width: 70px; }
.calendar-table th.student-name { background: #f1f5f9; z-index: 3; }
.calendar-table .weekend { background: #f8fafc; color: var(--text-secondary); }

.cell-status {
    cursor: pointer;
    border-radius: 4px;
    display: inline-block;
    width: 28px;
    height: 28px;
    line-height: 28px;
    font-size: 0.75rem;
    font-weight: 600;
    transition: transform 0.15s;
}
.cell-status:hover { transform: scale(1.15); }
.status-empty { background: transparent; color: #94a3b8; }
.status-present { background: transparent; color: var(--success); }
.status-late { background: transparent; color: var(--success); }

.calendar-legend {
    display: flex;
    gap: 12px;
    margin-top: 12px;
    flex-wrap: wrap;
    font-size: 0.8rem;
}
.legend-item { display: flex; align-items: center; gap: 4px; }
.legend-dot { width: 16px; height: 16px; border-radius: 3px; }
.status-paid { background: transparent; color: var(--success); }
.status-unpaid { background: transparent; color: var(--danger); }

/* ===== 查看考勤页面 ===== */
.cal-filter-bar {
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
    align-items: flex-end;
    margin-bottom: 12px;
}
.cal-filter-item { flex: 0 1 auto; min-width: 120px; }
.cal-filter-item .form-select,
.cal-filter-item .form-input { min-width: 130px; }
.cal-filter-nav {
    display: flex;
    gap: 4px;
    flex-shrink: 0;
}
.cal-student-card { margin-bottom: 20px; }
.cal-student-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 6px;
    flex-wrap: wrap;
    gap: 4px;
}
.cal-student-name { font-size: 1.05rem; }
.cal-billing-info { font-size: 0.85rem; color: var(--text-secondary); }
.cal-billing-unpaid { color: var(--danger); }
.cal-cell {
    padding: 4px;
    text-align: center;
    vertical-align: top;
    min-height: 48px;
}
.cal-today {
    box-shadow: inset 0 0 0 2px var(--primary);
    border-radius: 4px;
}
.cal-outside { opacity: 0.3; }
.cal-paid { background: #d1fae5; }
.cal-unpaid { color: #dc2626; font-weight: bold; margin-right: 4px; }
.cal-period-start { border-left: 3px solid var(--success); }
.cal-period-end { border-right: 3px solid var(--success); }
.cal-day-num { font-size: 0.75rem; color: var(--text-secondary); }

/* ===== 统计卡片 ===== */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
}
@media (min-width: 480px) { .stats-grid { grid-template-columns: repeat(3, 1fr); gap: 12px; } }
@media (min-width: 768px) { .stats-grid { grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 16px; margin-bottom: 24px; } }
.stat-card {
    background: var(--glass-bg);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    border: 1px solid var(--card-border);
    border-radius: var(--radius-lg);
    padding: var(--spacing-md);
    box-shadow: var(--glass-shadow);
    text-align: center;
    transition: all var(--transition);
}
@media (min-width: 768px) { .stat-card { padding: 20px; text-align: left; } }
.stat-card:hover { box-shadow: var(--shadow-md); transform: translateY(-2px); }
.stat-value {
    font-size: 1.6rem;
    font-weight: 700;
    color: var(--primary);
    line-height: 1.2;
}
@media (min-width: 768px) { .stat-value { font-size: 1.8rem; } }
.stat-label {
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin-top: 4px;
}
@media (min-width: 768px) { .stat-label { font-size: 0.85rem; } }

/* ===== 考勤标记网格 ===== */
.mark-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: var(--spacing-sm);
    margin-top: var(--spacing-sm);
}
@media (min-width: 480px) { .mark-grid { grid-template-columns: repeat(auto-fill, minmax(170px, 1fr)); gap: 10px; } }
@media (min-width: 768px) { .mark-grid { grid-template-columns: repeat(auto-fill, minmax(180px, 1fr)); gap: 12px; } }
.mark-card {
    background: var(--glass-bg);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    border: 1px solid var(--card-border);
    border-radius: var(--radius-lg);
    padding: 14px 12px;
    text-align: center;
    transition: all var(--transition);
}
.mark-card:hover { box-shadow: var(--shadow-md); transform: translateY(-2px); }
.mark-card .student-name {
    font-weight: 600;
    font-size: 0.95rem;
    margin-bottom: 10px;
    display: block;
}
.mark-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 7px 16px;
    border: none;
    border-radius: 6px;
    font-size: 0.85rem;
    font-weight: 600;
    cursor: pointer;
    min-width: 90px;
    min-height: 36px;
    transition: transform 0.15s, box-shadow 0.15s;
    -webkit-tap-highlight-color: transparent;
}
.mark-btn:active { transform: scale(0.95); }

/* ===== 数据网格卡片（通用） ===== */
.data-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-sm);
}
@media (min-width: 480px) { .data-grid { grid-template-columns: repeat(2, 1fr); gap: 10px; } }
@media (min-width: 768px) { .data-grid { grid-template-columns: repeat(auto-fill, minmax(320px, 1fr)); gap: 12px; } }
.data-card {
    background: var(--glass-bg);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    border: 1px solid var(--card-border);
    border-radius: var(--radius-lg);
    padding: var(--spacing-md);
    transition: all var(--transition);
}
.data-card:hover { box-shadow: var(--shadow-md); transform: translateY(-2px); }
.data-card .card-title {
    font-weight: 600;
    font-size: 1rem;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 6px;
    flex-wrap: wrap;
}
.data-card .card-body {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 6px 16px;
    font-size: 0.85rem;
    margin-bottom: 10px;
}
.data-card .field { display: flex; }
.data-card .field.full { grid-column: 1 / -1; }
.data-card .field-label { color: var(--text-secondary); flex-shrink: 0; white-space: nowrap; }
.data-card .field-label::after { content: '：'; }
.data-card .field-value { font-weight: 500; word-break: break-word; }
.data-card .card-actions {
    display: flex;
    gap: 6px;
    flex-wrap: wrap;
    padding-top: 10px;
    border-top: 1px solid var(--border);
}
.data-card .card-check {
    margin-right: auto;
    display: flex;
    align-items: center;
    gap: 4px;
    font-size: 0.8rem;
    color: var(--text-secondary);
}

/* ===== 分页 ===== */
.pagination { display: flex; gap: 4px; justify-content: center; margin-top: var(--spacing-md); flex-wrap: wrap; }
.pagination a, .pagination span {
    padding: 7px 14px;
    border: 1px solid var(--border);
    border-radius: 8px;
    font-size: 0.85rem;
    transition: all var(--transition);
}
.pagination a:hover { background: var(--primary); color: #fff; text-decoration: none; }
.pagination .current { background: var(--primary); color: #fff; border-color: var(--primary); }

/* ===== 搜索栏 ===== */
.search-bar {
    display: flex;
    gap: var(--spacing-sm);
    align-items: center;
    flex-wrap: wrap;
}
.search-bar .form-input, .search-bar .form-select {
    width: auto;
    min-width: 140px;
}
@media (max-width: 480px) {
    .search-bar .form-input, .search-bar .form-select {
        width: 100%;
        min-width: auto;
        flex: 1;
    }
    .search-bar .btn { width: 100%; }
}

/* ===== 登录页 ===== */
.login-page {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #1e40af 0%, #3b82f6 40%, #60a5fa 100%);
    padding: var(--spacing-md);
    position: relative;
    overflow: hidden;
}
.login-page::before {
    content: '';
    position: absolute;
    width: 400px;
    height: 400px;
    background: radial-gradient(circle, rgba(255,255,255,0.08) 0%, transparent 70%);
    top: -100px;
    right: -100px;
    border-radius: 50%;
}
.login-page::after {
    content: '';
    position: absolute;
    width: 300px;
    height: 300px;
    background: radial-gradient(circle, rgba(255,255,255,0.06) 0%, transparent 70%);
    bottom: -80px;
    left: -80px;
    border-radius: 50%;
}
.login-card {
    background: var(--glass-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--card-border);
    border-radius: var(--radius-lg);
    padding: 28px 24px;
    width: 100%;
    max-width: 380px;
    box-shadow: 0 20px 40px rgba(0,0,0,0.12);
}
@media (min-width: 480px) { .login-card { padding: 32px; } }
.login-title { text-align: center; margin-bottom: var(--spacing-lg); }
.login-title h1 { font-size: 1.35rem; margin-bottom: 4px; }
.login-title p { font-size: 0.85rem; color: var(--text-secondary); }
.role-tabs {
    display: flex;
    border: 1px solid var(--border);
    border-radius: 8px;
    overflow: hidden;
    margin-bottom: 20px;
}
.role-tab {
    flex: 1;
    padding: 10px;
    text-align: center;
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 500;
    background: #f8fafc;
    border: none;
    transition: all var(--transition);
}
.role-tab.active { background: var(--primary); color: #fff; }

/* ===== 空状态 ===== */
.empty-state { text-align: center; padding: 40px 20px; color: var(--text-secondary); }
.empty-state p { font-size: 0.95rem; }

/* ===== 移动端响应式 ===== */
@media (max-width: 767px) {
    /* ── 导航 ── */
    .nav-links {
        display: none;
        position: absolute;
        top: var(--nav-height);
        left: 0;
        right: 0;
        background: rgba(30,41,59,0.95);
        backdrop-filter: blur(12px);
        -webkit-backdrop-filter: blur(12px);
        flex-direction: row;
        flex-wrap: wrap;
        gap: 4px;
        padding: 8px;
        box-shadow: 0 8px 30px rgba(0,0,0,0.2);
        border-top: 1px solid rgba(255,255,255,0.08);
        animation: slideDown 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    }
    .nav-links.open { display: flex; }
    .nav-links a {
        padding: 8px 14px;
        font-size: 0.9rem;
        border-radius: 8px;
    }
    .nav-links a:active { background: rgba(255,255,255,0.2); }
    .hamburger { display: block; }

    /* ── 表格卡片式布局 ── */
    .table thead { display: none; }
    .table tr {
        display: block;
        margin-bottom: var(--spacing-sm);
        border: 1px solid var(--border);
        border-radius: var(--radius);
        padding: var(--spacing-sm) 12px;
        background: var(--card-bg);
    }
    .table td {
        display: flex;
        justify-content: space-between;
        align-items: center;
        border: none;
        padding: 7px 0;
        white-space: normal;
        word-break: break-word;
    }
    .table td::before {
        content: attr(data-label);
        font-weight: 600;
        color: var(--text-secondary);
        margin-right: 12px;
        flex-shrink: 0;
        font-size: 0.8rem;
    }
    .table .actions { justify-content: flex-end; gap: 4px; padding-top: 4px; border-top: 1px solid var(--border); margin-top: 4px; }

    /* ── 日历 ── */
    .calendar-controls { flex-direction: column; align-items: stretch; }
    .cal-filter-bar { flex-direction: column; align-items: stretch; }
    .cal-filter-item { min-width: auto; width: 100%; }
    .cal-filter-item .form-select,
    .cal-filter-item .form-input { min-width: auto; width: 100%; }
    .cal-filter-nav { justify-content: center; width: 100%; }
    .cal-filter-nav .btn { flex: 1; }
    .cal-student-header { flex-direction: column; align-items: flex-start; gap: 2px; }
    .cal-billing-info { font-size: 0.78rem; }
    .calendar-table { min-width: 320px; font-size: 0.7rem; }
    .calendar-table th, .calendar-table td { padding: 2px 1px; min-width: 28px; }
    .cal-cell { padding: 2px; }
    .cell-status { width: 22px; height: 22px; line-height: 22px; font-size: 0.65rem; }
    .cal-day-num { font-size: 0.65rem; }
    .calendar-legend { font-size: 0.72rem; gap: 6px; }
    .legend-dot { width: 12px; height: 12px; }
}

/* 下拉动画 */
@keyframes slideDown {
    from { opacity: 0; transform: translateY(-8px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ===== 打印标题（默认隐藏） ===== */
.print-header { display: none; }

/* ===== 收据样式 ===== */
.receipt-print { display: none; }
.receipt-card { max-width: 500px; margin: 0 auto; padding: 20px; text-align: center; }
.receipt-title { font-size: 1.3rem; margin-bottom: 4px; }
.receipt-subtitle { font-size: 1rem; margin-bottom: 16px; font-weight: normal; color: var(--text-secondary); }
.receipt-table { width: 100%; border-collapse: collapse; text-align: left; }
.receipt-table td { padding: 8px 12px; border-bottom: 1px solid var(--border); }
.receipt-label { font-weight: 600; width: 100px; color: var(--text-secondary); }
.receipt-amount { font-weight: bold; font-size: 1.1rem; color: var(--danger); }
.receipt-page-break { page-break-after: always; }

/* ===== 报名单打印样式 ===== */
.enroll-form-print { display: none; }
.enroll-form-header { text-align: center; margin-bottom: 16px; border-bottom: 2px solid #333; padding-bottom: 8px; }
.enroll-form-header h1 { font-size: 1.3rem; margin-bottom: 2px; }
.enroll-form-header h2 { font-size: 1rem; font-weight: normal; }
.enroll-form-body { font-size: 0.9rem; }
.enroll-form-top { display: flex; gap: 16px; margin-bottom: 12px; align-items: flex-start; flex-wrap: wrap; }
.enroll-form-avatar img { border: 1px solid #ccc; }
.enroll-form-info table { border-collapse: collapse; width: 100%; }
.enroll-form-info td { padding: 4px 8px; border: 1px solid #ddd; font-size: 0.85rem; }
.enroll-form-info td.label { font-weight: 600; background: #f5f5f5; width: 70px; }
.enroll-form-section { margin-bottom: 12px; border-top: 1px solid #ddd; padding-top: 8px; }
.enroll-form-section h3 { font-size: 0.95rem; margin-bottom: 6px; }

/* ===== 打印媒体查询 ===== */
@media print {
    @page { size: A4 portrait; margin: 15mm; }
    body { background: #fff; color: #000; }
    .nav, .no-print, .cal-filter-bar, .toast-container,
    .modal-overlay, .search-bar { display: none !important; }
    .card { box-shadow: none; border: none; padding: 0; margin: 0; }
    .page-content { padding: 0; }
    .container { max-width: 100%; padding: 0; }

    .print-header { display: block !important; text-align: center; font-size: 14pt; font-weight: bold; margin-bottom: 8px; }
    .calendar-table { min-width: auto; font-size: 9pt; }
    .calendar-table th, .calendar-table td { border-color: #999; padding: 3px 2px; }
    .calendar-table-wrap { overflow: visible; border: none; }
    .cal-student-card { page-break-inside: avoid; margin-bottom: 16px; }
    .cal-student-header { margin-bottom: 4px; }
    .cal-paid { background: #eee; }
    .cal-period-start { border-left: 2px solid #333; }
    .cal-period-end { border-right: 2px solid #333; }
    .status-present { background: transparent; color: var(--success); }
    .status-late    { background: transparent; color: var(--success); }
    .calendar-legend { font-size: 8pt; }

    body.printing-receipt > *:not(.receipt-print) { display: none !important; }
    body.printing-receipt .receipt-print { display: block !important; position: static; }
    .receipt-card { max-width: 100%; padding: 0; }
    .receipt-table td { border-color: #999; }

    body.printing-enroll .nav,
    body.printing-enroll .toast-container,
    body.printing-enroll .modal-overlay,
    body.printing-enroll .page-content > *:not(.enroll-form-print) { display: none !important; }
    body.printing-enroll .enroll-form-print { display: block !important; }
    body.printing-enroll .page-content { padding: 0; }
    body.printing-enroll .container { max-width: 100%; }
    .enroll-form-info td { border-color: #999; }
    .enroll-form-section { border-color: #999; }
}

/* 课程价格tips */
.price-tip-wrap {
    position: relative;
    display: inline-block;
}
.price-tip-content {
    display: none;
    position: absolute;
    left: 0;
    top: 100%;
    margin-top: 6px;
    background: rgba(30,41,59,0.95);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    color: #f8fafc;
    padding: 10px 14px;
    border-radius: 8px;
    font-size: 13px;
    line-height: 1.6;
    white-space: nowrap;
    z-index: 100;
    min-width: 160px;
    box-shadow: 0 8px 25px rgba(0,0,0,0.2);
    border: 1px solid rgba(255,255,255,0.1);
    animation: fadeIn 0.2s ease;
}
.price-tip-wrap.active .price-tip-content { display: block; }

/* ===== 工具类 ===== */
.text-center { text-align: center; }
.text-right { text-align: right; }
.hidden { display: none !important; }