/* ========== 千川助手 - 全局样式 ========== */
* { margin:0; padding:0; box-sizing:border-box; }
:root {
    --primary: #4f46e5;
    --primary-hover: #4338ca;
    --primary-light: #eef2ff;
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-400: #9ca3af;
    --gray-500: #6b7280;
    --gray-600: #4b5563;
    --gray-700: #374151;
    --gray-800: #1f2937;
    --gray-900: #111827;
    --radius: 10px;
    --shadow: 0 1px 3px rgba(0,0,0,.08), 0 1px 2px rgba(0,0,0,.06);
    --shadow-lg: 0 4px 16px rgba(0,0,0,.1);
}
body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--gray-100);
    color: var(--gray-800);
    line-height: 1.6;
    min-height: 100vh;
}

/* ===== 导航栏 ===== */
.navbar {
    background: #fff;
    border-bottom: 1px solid var(--gray-200);
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow);
}
.nav-inner {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    align-items: center;
    height: 58px;
    gap: 8px;
}
.nav-logo {
    font-size: 18px;
    font-weight: 700;
    color: var(--primary);
    text-decoration: none;
    margin-right: 24px;
    white-space: nowrap;
}
.nav-links {
    display: flex;
    align-items: center;
    gap: 4px;
    flex: 1;
}
.nav-link {
    padding: 8px 16px;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 500;
    color: var(--gray-600);
    text-decoration: none;
    transition: all .15s;
    white-space: nowrap;
}
.nav-link:hover { background: var(--gray-100); color: var(--gray-900); }
.nav-link.active { background: var(--primary-light); color: var(--primary); }
.nav-user {
    margin-left: auto;
    font-size: 13px;
    color: var(--gray-500);
    padding: 8px 12px;
}
.nav-logout { color: var(--danger) !important; font-size: 13px; }

/* ===== 主内容区 ===== */
.main-content {
    max-width: 1280px;
    margin: 0 auto;
    padding: 24px;
}

/* ===== 页面标题 ===== */
.page-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 24px;
    flex-wrap: wrap;
    gap: 12px;
}
.page-title {
    font-size: 22px;
    font-weight: 700;
    color: var(--gray-900);
}
.page-subtitle {
    font-size: 14px;
    color: var(--gray-500);
    margin-top: 2px;
}

/* ===== 卡片 ===== */
.card {
    background: #fff;
    border-radius: var(--radius);
    padding: 24px;
    box-shadow: var(--shadow);
    margin-bottom: 20px;
}
.card-title {
    font-size: 16px;
    font-weight: 600;
    color: var(--gray-800);
    margin-bottom: 16px;
    display: flex;
    align-items: center;
    gap: 8px;
}

/* ===== 统计卡片网格 ===== */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 16px;
    margin-bottom: 24px;
}
.stat-card {
    background: #fff;
    border-radius: var(--radius);
    padding: 20px 24px;
    box-shadow: var(--shadow);
    display: flex;
    flex-direction: column;
    transition: transform .15s;
}
.stat-card:hover { transform: translateY(-2px); }
.stat-label {
    font-size: 12px;
    font-weight: 600;
    color: var(--gray-500);
    text-transform: uppercase;
    letter-spacing: .5px;
    margin-bottom: 8px;
}
.stat-value {
    font-size: 28px;
    font-weight: 700;
    color: var(--gray-900);
}
.stat-sub {
    font-size: 12px;
    color: var(--gray-400);
    margin-top: 4px;
}
.stat-card.primary .stat-value { color: var(--primary); }
.stat-card.success .stat-value { color: var(--success); }
.stat-card.warning .stat-value { color: var(--warning); }
.stat-card.danger .stat-value { color: var(--danger); }

/* ===== 按钮 ===== */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 10px 20px;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    border: none;
    text-decoration: none;
    transition: all .15s;
    white-space: nowrap;
}
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-hover); }
.btn-success { background: var(--success); color: #fff; }
.btn-success:hover { background: #059669; }
.btn-danger { background: var(--danger); color: #fff; }
.btn-danger:hover { background: #dc2626; }
.btn-outline { background: #fff; color: var(--primary); border: 1.5px solid var(--primary); }
.btn-outline:hover { background: var(--primary-light); }
.btn-sm { padding: 6px 12px; font-size: 12px; }
.btn-lg { padding: 14px 28px; font-size: 16px; }

/* ===== 表单 ===== */
.form-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 16px;
}
.form-group { margin-bottom: 0; }
.form-group.full { grid-column: 1 / -1; }
.form-group label {
    display: block;
    font-size: 13px;
    font-weight: 600;
    color: var(--gray-700);
    margin-bottom: 6px;
}
.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 10px 14px;
    border: 1.5px solid var(--gray-300);
    border-radius: 8px;
    font-size: 14px;
    color: var(--gray-800);
    transition: border .2s;
    outline: none;
    background: #fff;
}
.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(79,70,229,.1);
}
.form-group textarea { resize: vertical; min-height: 80px; }
.form-group .hint { font-size: 11px; color: var(--gray-400); margin-top: 4px; }

/* ===== 表格 ===== */
.table-wrap { overflow-x: auto; }
table { width: 100%; border-collapse: collapse; font-size: 13px; }
table th {
    background: var(--gray-50);
    padding: 10px 12px;
    text-align: left;
    font-weight: 600;
    color: var(--gray-600);
    border-bottom: 2px solid var(--gray-200);
    white-space: nowrap;
}
table td {
    padding: 10px 12px;
    border-bottom: 1px solid var(--gray-100);
    color: var(--gray-700);
}
table tbody tr:hover { background: var(--gray-50); }
table .text-right { text-align: right; }
table .text-center { text-align: center; }

/* ===== ROI 颜色 ===== */
.roi-high { color: var(--success); font-weight: 700; }
.roi-mid { color: var(--warning); font-weight: 600; }
.roi-low { color: var(--danger); font-weight: 600; }

/* ===== 标签/Badge ===== */
.badge {
    display: inline-block;
    padding: 3px 10px;
    border-radius: 20px;
    font-size: 11px;
    font-weight: 600;
}
.badge-success { background: #d1fae5; color: #065f46; }
.badge-warning { background: #fef3c7; color: #92400e; }
.badge-danger { background: #fee2e2; color: #991b1b; }
.badge-info { background: #dbeafe; color: #1e40af; }
.badge-purple { background: #ede9fe; color: #5b21b6; }

/* ===== 弹窗 ===== */
.modal-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,.4);
    z-index: 1000;
    align-items: center;
    justify-content: center;
}
.modal-overlay.active { display: flex; }
.modal-box {
    background: #fff;
    border-radius: 12px;
    padding: 32px;
    max-width: 500px;
    width: 90%;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: var(--shadow-lg);
}
.modal-title { font-size: 18px; font-weight: 700; margin-bottom: 20px; }
.modal-actions { display: flex; gap: 10px; justify-content: flex-end; margin-top: 20px; }

/* ===== 加载/空状态 ===== */
.loading { text-align: center; padding: 40px; color: var(--gray-400); }
.empty-state { text-align: center; padding: 60px 20px; }
.empty-state .icon { font-size: 48px; margin-bottom: 16px; }
.empty-state h3 { font-size: 16px; color: var(--gray-600); margin-bottom: 8px; }
.empty-state p { font-size: 13px; color: var(--gray-400); margin-bottom: 20px; }

/* ===== 提示信息 ===== */
.alert { padding: 12px 16px; border-radius: 8px; font-size: 13px; margin-bottom: 16px; }
.alert-error { background: #fef2f2; color: #991b1b; border-left: 3px solid var(--danger); }
.alert-success { background: #ecfdf5; color: #065f46; border-left: 3px solid var(--success); }
.alert-info { background: #eff6ff; color: #1e40af; border-left: 3px solid var(--primary); }
.alert-warning { background: #fffbeb; color: #92400e; border-left: 3px solid var(--warning); }

/* ===== 工具栏 ===== */
.toolbar {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
    align-items: center;
    margin-bottom: 16px;
}
.toolbar .search-input {
    padding: 8px 14px;
    border: 1.5px solid var(--gray-300);
    border-radius: 8px;
    font-size: 13px;
    width: 240px;
    outline: none;
}
.toolbar .search-input:focus { border-color: var(--primary); }
.toolbar select {
    padding: 8px 12px;
    border: 1.5px solid var(--gray-300);
    border-radius: 8px;
    font-size: 13px;
    background: #fff;
    outline: none;
}

/* ===== 上传区域 ===== */
.upload-zone {
    border: 2px dashed var(--gray-300);
    border-radius: var(--radius);
    padding: 40px 24px;
    text-align: center;
    cursor: pointer;
    transition: all .2s;
    background: var(--gray-50);
}
.upload-zone:hover, .upload-zone.dragover {
    border-color: var(--primary);
    background: var(--primary-light);
}
.upload-zone .upload-icon { font-size: 40px; margin-bottom: 12px; }
.upload-zone p { font-size: 14px; color: var(--gray-500); }
.upload-zone .upload-hint { font-size: 12px; color: var(--gray-400); margin-top: 6px; }

/* ===== ROI推荐卡片 ===== */
.roi-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 16px;
    margin-bottom: 24px;
}
.roi-card {
    background: #fff;
    border-radius: var(--radius);
    padding: 24px;
    box-shadow: var(--shadow);
    text-align: center;
    border-top: 3px solid var(--gray-300);
}
.roi-card.conservative { border-top-color: var(--warning); }
.roi-card.recommended { border-top-color: var(--primary); }
.roi-card.optimistic { border-top-color: var(--success); }
.roi-card .roi-label { font-size: 13px; font-weight: 600; color: var(--gray-500); margin-bottom: 8px; }
.roi-card .roi-number { font-size: 36px; font-weight: 800; }
.roi-card .roi-tip { font-size: 12px; color: var(--gray-400); margin-top: 8px; }

/* ===== 响应式 ===== */
@media (max-width: 768px) {
    .nav-inner { flex-wrap: wrap; height: auto; padding: 10px 16px; }
    .nav-links { order: 3; width: 100%; overflow-x: auto; }
    .nav-user { margin-left: 0; }
    .form-grid { grid-template-columns: 1fr; }
    .stats-grid { grid-template-columns: repeat(2, 1fr); }
    .roi-cards { grid-template-columns: 1fr; }
    .page-header { flex-direction: column; align-items: flex-start; }
}