/* 基础样式 */
* { margin: 0; padding: 0; box-sizing: border-box; }

:root {
    --primary: #2563eb;
    --success: #16a34a;
    --danger: #dc2626;
    --warning: #f59e0b;
    --secondary: #64748b;
    --bg: #f8fafc;
    --card: #fff;
    --text: #1e293b;
    --border: #e2e8f0;
}

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

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 20px;
}

header {
    background: linear-gradient(135deg, var(--primary), #1e40af);
    color: white;
    padding: 24px 30px;
    border-radius: 12px;
    margin-bottom: 24px;
}

header h1 { font-size: 24px; font-weight: 600; }

/* 标签页 */
.tab-container {
    display: flex;
    gap: 8px;
    margin-bottom: 20px;
    background: var(--card);
    padding: 8px;
    border-radius: 10px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

.tab-btn {
    flex: 1;
    padding: 10px 16px;
    background: transparent;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    color: var(--secondary);
    transition: all 0.2s;
}

.tab-btn:hover { background: var(--bg); }
.tab-btn.active { background: var(--primary); color: white; }

.tab-content { display: none; }
.tab-content.active { display: block; animation: fadeIn 0.3s; }

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* 统计卡片 */
.stats-cards {
    display: flex;
display: flex;
display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
    margin-bottom: 20px;
}

.stat-card {
    background: var(--card);
    padding: 20px;
    border-radius: 10px;
    text-align: center;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

.stat-label { color: var(--secondary); font-size: 13px; margin-bottom: 6px; }
.stat-value { font-size: 28px; font-weight: 700; color: var(--primary); }
.stat-value.warning { color: var(--warning); }
.stat-value.danger { color: var(--danger); }

/* 操作栏 */
.action-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 16px;
    gap: 12px;
    flex-wrap: wrap;
}

.search-input {
    flex: 1;
    max-width: 280px;
    padding: 10px 14px;
    border: 2px solid var(--border);
    border-radius: 8px;
    font-size: 14px;
    outline: none;
}

.search-input:focus { border-color: var(--primary); }

/* 按钮 */
.btn {
    padding: 10px 18px;
    border: none;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
}

.btn:hover { transform: translateY(-1px); }
.btn-primary { background: var(--primary); color: white; }
.btn-success { background: var(--success); color: white; }
.btn-danger { background: var(--danger); color: white; }
.btn-secondary { background: var(--secondary); color: white; }
.btn-warning { background: var(--warning); color: white; }
.btn-outline { background: transparent; border: 1px solid var(--primary); color: var(--primary); }
.btn-outline:hover { background: var(--primary); color: white; }
.btn-small { padding: 6px 12px; font-size: 13px; }
.btn-tiny { padding: 4px 10px; font-size: 12px; }

/* 表格 */
.data-table {
    width: 100%;
    background: var(--card);
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

.data-table thead { background: var(--bg); }
.data-table th { padding: 14px; text-align: left; font-weight: 600; border-bottom: 2px solid var(--border); }
.data-table td { padding: 14px; border-bottom: 1px solid var(--border); }
.data-table tbody tr:hover { background: var(--bg); }

.status-badge {
    display: inline-block;
    padding: 3px 10px;
    border-radius: 12px;
    font-size: 12px;
    font-weight: 500;
}
.status-normal { background: #dcfce7; color: #16a34a; }
.status-low { background: #fef3c7; color: #f59e0b; }

/* 表单 */
.form-container {
    background: var(--card);
    padding: 24px;
    border-radius: 10px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
    max-width: 480px;
    margin: 0 auto;
}

.form-container h2 { margin-bottom: 20px; font-size: 18px; }

.form-group { margin-bottom: 16px; }
.form-group label { display: block; margin-bottom: 6px; font-weight: 500; font-size: 14px; }
.form-group input, .form-group select, .form-group textarea {
    width: 100%;
    padding: 10px 12px;
    border: 2px solid var(--border);
    border-radius: 8px;
    font-size: 14px;
    font-family: inherit;
    outline: none;
}
.form-group input:focus, .form-group select:focus, .form-group textarea:focus { border-color: var(--primary); }

.current-stock { display: block; margin-top: 4px; color: var(--secondary); font-size: 13px; }
.current-stock span { font-weight: 600; color: var(--primary); }

/* ============= 借还 Tab 专属样式 ============= */

/* 布局：宽屏两列 */
.borrow-layout {
    display: grid;
    grid-template-columns: 340px 1fr;
    gap: 24px;
    align-items: start;
}
.borrow-form-section { position: sticky; top: 20px; }
.borrow-list-section { min-width: 0; }

/* 借还子选项卡 */
.borrow-sub-tabs {
    display: flex;
    gap: 4px;
    margin-bottom: 16px;
    background: var(--bg);
    padding: 4px;
    border-radius: 8px;
}
.borrow-sub-tab {
    flex: 1;
    padding: 8px 12px;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-size: 13px;
    font-weight: 500;
    background: transparent;
    color: var(--secondary);
    transition: all 0.2s;
}
.borrow-sub-tab:hover { background: var(--card); }
.borrow-sub-tab.active { background: var(--card); color: var(--text); box-shadow: 0 1px 2px rgba(0,0,0,0.1); }
.borrow-sub-tab .count { color: var(--primary); font-weight: 600; }

/* 搜索/筛选 */
.borrow-toolbar {
    display: flex;
    gap: 8px;
    margin-bottom: 16px;
    flex-wrap: wrap;
}
.borrow-toolbar .search-input { max-width: 160px; }
.borrow-toolbar select {
    padding: 8px 12px;
    border: 2px solid var(--border);
    border-radius: 8px;
    font-size: 13px;
    outline: none;
    background: var(--card);
    min-width: 100px;
}

/* 借还卡片 */
.borrow-card {
    background: var(--card);
    border-radius: 10px;
    padding: 16px;
    margin-bottom: 12px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.08);
    border-left: 4px solid transparent;
    transition: box-shadow 0.2s;
}
.borrow-card:hover { box-shadow: 0 2px 8px rgba(0,0,0,0.12); }
.borrow-card.card-overdue { border-left-color: var(--danger); background: #fef2f2; }
.borrow-card.card-active { border-left-color: var(--primary); }
.borrow-card.card-returned { border-left-color: var(--success); opacity: 0.85; }

.borrow-card-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 6px;
}
.borrow-card-header .item-name { font-size: 15px; font-weight: 600; color: var(--text); }
.borrow-card-header .item-qty { font-size: 14px; color: var(--primary); font-weight: 600; white-space: nowrap; }

.borrow-card-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 4px 16px;
    font-size: 13px;
    color: var(--secondary);
    margin-bottom: 6px;
}
.borrow-card-meta .meta-label { color: var(--secondary); }
.borrow-card-meta .overdue-tag { color: var(--danger); font-weight: 600; }

.borrow-card-remark {
    font-size: 12px;
    color: var(--secondary);
    background: #f1f5f9;
    padding: 6px 10px;
    border-radius: 6px;
    margin-bottom: 8px;
    word-break: break-all;
}

/* 进度条 */
.return-progress { margin-bottom: 8px; }
.return-progress .progress-labels {
    display: flex;
    justify-content: space-between;
    font-size: 12px;
    color: var(--secondary);
    margin-bottom: 3px;
}
.return-progress .progress-track {
    height: 5px;
    background: var(--border);
    border-radius: 3px;
    overflow: hidden;
}
.return-progress .progress-fill {
    height: 100%;
    border-radius: 3px;
    background: var(--primary);
    transition: width 0.3s;
}
.return-progress .progress-fill.full { background: var(--success); }

.borrow-card-actions {
    display: flex;
    gap: 6px;
    justify-content: flex-end;
    flex-wrap: wrap;
}

/* 快捷数量按钮 */
.qty-group {
    display: flex;
    gap: 6px;
    flex-wrap: wrap;
    margin-top: 4px;
}
.qty-btn {
    padding: 4px 12px;
    border: 1px solid var(--border);
    border-radius: 6px;
    background: var(--card);
    cursor: pointer;
    font-size: 13px;
    color: var(--secondary);
    transition: all 0.15s;
}
.qty-btn:hover { border-color: var(--primary); color: var(--primary); background: #eff6ff; }

/* 库存预览 */
.stock-preview {
    display: flex;
    gap: 16px;
    margin-top: 4px;
    font-size: 13px;
    color: var(--secondary);
}
.stock-preview .sp-item { display: inline-flex; align-items: center; gap: 3px; }
.stock-preview .sp-num { font-weight: 600; }
.stock-preview .sp-num.in-stock { color: var(--primary); }
.stock-preview .sp-num.borrowed { color: var(--warning); }

/* 输入错误 */
.input-error { border-color: var(--danger) !important; }
.error-text { color: var(--danger); font-size: 12px; margin-top: 2px; }

/* 归还模态信息卡 */
.return-info-card {
    background: #f1f5f9;
    border-radius: 10px;
    padding: 16px;
    margin-bottom: 16px;
}
.return-info-card .info-row {
    display: flex;
    justify-content: space-between;
    padding: 3px 0;
    font-size: 13px;
}
.return-info-card .info-row .il { color: var(--secondary); }
.return-info-card .info-row .iv { font-weight: 500; }
.return-info-card .info-row .iv.overdue { color: var(--danger); font-weight: 600; }
.return-info-card .info-divider { border: none; border-top: 1px solid var(--border); margin: 8px 0; }
.return-info-card .qty-overview {
    display: flex;
    justify-content: space-around;
    text-align: center;
    margin: 8px 0;
}
.return-info-card .qty-overview .qi { flex: 1; }
.return-info-card .qty-overview .qn { font-size: 22px; font-weight: 700; color: var(--primary); }
.return-info-card .qty-overview .qn.returned { color: var(--success); }
.return-info-card .qty-overview .qn.remaining { color: var(--warning); }
.return-info-card .qty-overview .ql { font-size: 11px; color: var(--secondary); }

/* 备份/同步 */
.backup-container {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
}

.backup-section {
    background: var(--card);
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

.backup-section h3 { margin-bottom: 16px; font-size: 16px; }

.backup-buttons {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.sync-status {
    padding: 8px 12px;
    border-radius: 6px;
    background: var(--bg);
    margin-bottom: 12px;
    font-size: 13px;
}

/* 模态框 */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5);
}

.modal.active { display: flex; align-items: center; justify-content: center; }

.modal-content {
    background: var(--card);
    padding: 24px;
    border-radius: 12px;
    width: 90%;
    max-width: 460px;
    animation: slideUp 0.3s;
}

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

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.modal-header h2 { font-size: 18px; }
.close { font-size: 26px; color: var(--secondary); cursor: pointer; }
.close:hover { color: var(--danger); }

.modal-actions {
    display: flex;
    gap: 10px;
    margin-top: 20px;
}
.modal-actions .btn { flex: 1; }

.return-info {
    background: var(--bg);
    padding: 12px;
    border-radius: 8px;
    margin-bottom: 16px;
}

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

/* 响应式 */
@media (max-width: 768px) {
    .stats-cards { grid-template-columns: repeat(2, 1fr); }
    .backup-container { grid-template-columns: 1fr; }
    .container { padding: 12px; }
    .borrow-layout { grid-template-columns: 1fr; }
    .borrow-form-section { position: static; }
    .borrow-toolbar .search-input { max-width: 100%; flex: 1; }
    .borrow-toolbar { flex-direction: column; }
}
.borrow-right-section {
    min-width: 0;
}
.return-panel {
    background: var(--card);
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}
.return-panel .return-info-card {
    background: #f1f5f9;
    border-radius: 10px;
    padding: 16px;
    margin-bottom: 16px;
}
.return-panel .return-info-card .info-row {
    display: flex;
    justify-content: space-between;
    padding: 3px 0;
    font-size: 13px;
}
.return-panel .return-info-card .info-row .il { color: var(--secondary); }
.return-panel .return-info-card .info-row .iv { font-weight: 500; }
.return-panel .return-info-card .info-row .iv.overdue { color: var(--danger); font-weight: 600; }
.return-panel .return-info-card .info-divider { border: none; border-top: 1px solid var(--border); margin: 8px 0; }
.return-panel .return-info-card .qty-overview {
    display: flex;
    justify-content: space-around;
    text-align: center;
    margin: 8px 0;
}
.return-panel .return-info-card .qty-overview .qi { flex: 1; }
.return-panel .return-info-card .qty-overview .qn { font-size: 22px; font-weight: 700; color: var(--primary); }
.return-panel .return-info-card .qty-overview .qn.returned { color: var(--success); }
.return-panel .return-info-card .qty-overview .qn.remaining { color: var(--warning); }
.return-panel .return-info-card .qty-overview .ql { font-size: 11px; color: var(--secondary); }
.return-panel .return-info-card .return-progress { margin-bottom: 0; }
.return-panel .return-info-card .return-progress .progress-track { height: 5px; background: var(--border); border-radius: 3px; overflow: hidden; }
.return-panel .return-info-card .return-progress .progress-fill { height: 100%; border-radius: 3px; background: var(--primary); transition: width 0.3s; }
.return-panel .return-info-card .return-progress .progress-fill.full { background: var(--success); }

/* 人卡片 */
.person-card {
    background: var(--card);
    border-radius: 10px;
    margin-bottom: 16px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.08);
    overflow: hidden;
    border-left: 4px solid var(--primary);
}
.person-card.overdue { border-left-color: var(--danger); background: #fefcfc; }
.person-card.overdue .person-card-header { background: #fef2f2; }

.person-card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 14px 16px;
    background: #f8faff;
    cursor: pointer;
    user-select: none;
}
.person-card-header .pc-name { font-size: 15px; font-weight: 600; }
.person-card-header .pc-stats { font-size: 13px; color: var(--secondary); }
.person-card-header .pc-stats .pc-num { font-weight: 600; color: var(--primary); }
.person-card-header .pc-stats .pc-ovd { color: var(--danger); font-weight: 600; }

.person-card-body {
    padding: 8px 16px 12px;
}

.person-borrow-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px 0;
    border-bottom: 1px solid #f0f0f0;
    gap: 8px;
}
.person-borrow-row:last-child { border-bottom: none; }

.pbr-info { flex: 1; min-width: 0; }
.pbr-info .pbr-item { font-size: 14px; font-weight: 500; }
.pbr-info .pbr-item .pbr-unit { font-weight: 400; color: var(--secondary); }
.pbr-info .pbr-meta { font-size: 12px; color: var(--secondary); margin-top: 2px; display: flex; gap: 8px; flex-wrap: wrap; }
.pbr-info .pbr-meta .ovd-tag { color: var(--danger); }
.pbr-info .pbr-remark { font-size: 12px; color: #777; background: #f5f5f5; padding: 2px 6px; border-radius: 4px; display: inline-block; margin-top: 2px; }

.pbr-actions { white-space: nowrap; }
.pbr-actions .btn-return { padding: 4px 10px; font-size: 12px; }

.person-card-footer {
    padding: 10px 16px;
    background: #fafafa;
    text-align: right;
    border-top: 1px solid #eee;
}