:root {
    --primary: #3b82f6;
    --primary-dark: #2563eb;
    --panel-bg: #ffffff;
    --page-bg: #f1f5f9;
    --text-main: #0f172a;
    --text-muted: #64748b;
    --border: #e2e8f0;
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: 'Segoe UI', Tahoma, Arial, sans-serif;
    color: var(--text-main);
    background: var(--page-bg);
    padding-top: 50px;
}

.embed-mode body {
    padding-top: 0;
}

.embed-mode .recuedu-topbar {
    padding-top: 0;
    display: none;
}

.app-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 14px 18px;
    background: var(--panel-bg);
    border-bottom: 1px solid var(--border);
}

.brand {
    display: flex;
    align-items: center;
    gap: 12px;
}

.brand i {
    font-size: 1.5rem;
    color: var(--primary);
}

.brand h1 {
    margin: 0;
    font-size: 1.35rem;
}

.subtitle {
    margin: 2px 0 0;
    color: var(--text-muted);
    font-size: 0.86rem;
}

.badge {
    font-size: 0.7rem;
    padding: 2px 6px;
    border-radius: 4px;
    color: #fff;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    vertical-align: middle;
}

.language-select {
    border: 1px solid var(--border);
    border-radius: 8px;
    background: #fff;
    padding: 8px 10px;
    font-size: 0.85rem;
}

.dashboard-layout {
    display: grid;
    grid-template-columns: 72px 360px 1fr;
    gap: 0;
    height: calc(100vh - 121px);
}

.nav-sidebar {
    background: var(--panel-bg);
    border-right: 1px solid var(--border);
    padding: 10px 8px;
    grid-column: 1;
    grid-row: 1;
}

.nav-menu {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.nav-item {
    border: 1px solid transparent;
    background: transparent;
    color: var(--text-muted);
    border-radius: 10px;
    padding: 10px 6px;
    cursor: pointer;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 5px;
}

.nav-item.active {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #fff;
}

.nav-icon {
    font-size: 1.1rem;
}

.nav-label {
    font-size: 0.72rem;
}

.chart-main {
    display: grid;
    grid-template-rows: auto 1fr;
    min-width: 0;
    grid-column: 3;
    grid-row: 1;
}

.chart-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 14px;
    background: var(--panel-bg);
    border-bottom: 1px solid var(--border);
}

.chart-header h2 {
    margin: 0;
    font-size: 1.1rem;
}

.dataset-chip {
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 6px 10px;
    font-size: 0.82rem;
    color: var(--text-muted);
    background: #fff;
}

.chart-container {
    padding: 14px;
    min-height: 0;
}

.chart-placeholder,
#chart-canvas {
    height: 100%;
    min-height: 420px;
    border: 1px dashed var(--border);
    border-radius: 12px;
    background: #fff;
}

.chart-placeholder {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: #94a3b8;
    text-align: center;
    padding: 24px;
}

.placeholder-icon {
    width: 72px;
    height: 72px;
    margin-bottom: 12px;
    stroke-width: 1.4;
}

.hidden {
    display: none !important;
}

.options-sidebar {
    background: var(--panel-bg);
    border-right: 1px solid var(--border);
    overflow-y: auto;
    padding: 12px;
    grid-column: 2;
    grid-row: 1;
}

.options-panel {
    display: none;
}

.options-panel.active {
    display: block;
}

.options-title {
    margin: 0 0 12px;
    font-size: 1rem;
    padding-bottom: 8px;
    border-bottom: 1px solid var(--border);
}

.option-group {
    margin-bottom: 12px;
}

.option-group.two-col {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 8px;
}

.option-label {
    display: block;
    font-size: 0.83rem;
    color: var(--text-muted);
    margin-bottom: 6px;
}

.select-input,
.number-input,
.text-input {
    width: 100%;
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 8px 10px;
    font-size: 0.86rem;
    background: #fff;
}

.checkbox-label {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 0.86rem;
}

.btn-primary,
.btn-secondary {
    width: 100%;
    border: none;
    border-radius: 8px;
    padding: 9px 12px;
    font-size: 0.86rem;
    cursor: pointer;
}

.btn-primary {
    background: var(--primary);
    color: #fff;
}

.btn-primary:hover {
    background: var(--primary-dark);
}

.btn-secondary {
    border: 1px solid var(--border);
    background: #fff;
    color: var(--text-main);
}

.data-summary {
    font-size: 0.8rem;
    border: 1px solid var(--border);
    border-radius: 8px;
    background: #f8fafc;
    padding: 10px;
    color: var(--text-muted);
}

.settings-section {
    border: 1px solid var(--border);
    border-radius: 10px;
    background: #f8fafc;
    margin-bottom: 10px;
    padding: 0 10px 8px;
}

.settings-section > summary {
    cursor: pointer;
    font-size: 0.83rem;
    font-weight: 600;
    color: #334155;
    padding: 10px 2px;
    list-style: none;
}

.settings-section > summary::-webkit-details-marker {
    display: none;
}

.settings-section > summary::after {
    content: '+';
    float: right;
    color: #64748b;
    font-weight: 700;
}

.settings-section[open] > summary::after {
    content: '-';
}

.settings-section .option-group:last-child {
    margin-bottom: 4px;
}

@media (max-width: 1100px) {
    .dashboard-layout {
        grid-template-columns: 64px 1fr;
    }

    .options-sidebar {
        display: none;
    }

    .chart-main {
        grid-column: 2;
        grid-row: 1;
    }
}