:root {
    --bg-primary: #0f0f12;
    --bg-secondary: #1a1a23;
    --bg-card: #1e1e2a;
    --bg-input: #252533;
    --border: #2d2d3d;
    --border-focus: #7c3aed;
    --text-primary: #f0f0f5;
    --text-secondary: #9090a8;
    --text-muted: #606078;
    --accent: #7c3aed;
    --accent-hover: #6d28d9;
    --accent-light: rgba(124, 58, 237, 0.15);
    --accent-glow: rgba(124, 58, 237, 0.4);
    --success: #22c55e;
    --warning: #f59e0b;
    --danger: #ef4444;
    --info: #3b82f6;
    --radius: 12px;
    --radius-sm: 8px;
    --shadow: 0 4px 24px rgba(0, 0, 0, 0.3);
    --font-mono: 'JetBrains Mono', monospace;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
}

.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Header */
.header {
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border);
    padding: 16px 0;
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(12px);
}

.header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 16px;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo-icon {
    font-size: 1.8rem;
}

.nav {
    display: flex;
    gap: 4px;
    background: var(--bg-input);
    padding: 4px;
    border-radius: var(--radius-sm);
}

.nav-btn {
    background: none;
    border: none;
    color: var(--text-secondary);
    padding: 8px 16px;
    border-radius: 6px;
    cursor: pointer;
    font-family: inherit;
    font-size: 0.875rem;
    font-weight: 500;
    transition: all 0.2s;
}

.nav-btn:hover {
    color: var(--text-primary);
    background: var(--bg-card);
}

.nav-btn.active {
    background: var(--accent);
    color: #fff;
}

/* Main */
.main {
    padding: 32px 24px;
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
}

/* Grid Layouts */
.grid-2 {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
    margin-bottom: 24px;
}

.grid-3 {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    margin-bottom: 24px;
}

/* Cards */
.card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 24px;
    box-shadow: var(--shadow);
}

.card-title {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 20px;
    color: var(--text-primary);
}

.card-desc {
    color: var(--text-secondary);
    font-size: 0.875rem;
    margin-bottom: 20px;
}

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

.card-header-row .card-title {
    margin-bottom: 0;
}

/* Inputs */
.input-group {
    margin-bottom: 16px;
}

.input-group label {
    display: block;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: 6px;
}

.input-wrapper {
    display: flex;
    align-items: center;
    background: var(--bg-input);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    overflow: hidden;
    transition: border-color 0.2s;
}

.input-wrapper:focus-within {
    border-color: var(--border-focus);
    box-shadow: 0 0 0 3px var(--accent-light);
}

.input-prefix,
.input-suffix {
    padding: 12px 14px;
    color: var(--text-muted);
    font-family: var(--font-mono);
    font-size: 0.875rem;
    background: var(--bg-secondary);
    user-select: none;
}

.input-wrapper input {
    flex: 1;
}

input[type="number"],
input[type="text"] {
    width: 100%;
    padding: 12px 14px;
    background: var(--bg-input);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    font-family: var(--font-mono);
    font-size: 0.95rem;
    outline: none;
    transition: border-color 0.2s;
}

.input-wrapper input {
    border: none;
    background: transparent;
}

input:focus {
    border-color: var(--border-focus);
    box-shadow: 0 0 0 3px var(--accent-light);
}

input::placeholder {
    color: var(--text-muted);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 24px;
    border: none;
    border-radius: var(--radius-sm);
    font-family: inherit;
    font-size: 0.875rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
}

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

.btn-primary:hover {
    background: var(--accent-hover);
    box-shadow: 0 4px 16px var(--accent-glow);
}

.btn-secondary {
    background: var(--bg-input);
    color: var(--text-primary);
    border: 1px solid var(--border);
}

.btn-secondary:hover {
    background: var(--bg-card);
    border-color: var(--accent);
}

.btn-outline {
    background: transparent;
    color: var(--accent);
    border: 1px solid var(--accent);
}

.btn-outline:hover {
    background: var(--accent-light);
}

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

.btn-danger:hover {
    background: #dc2626;
}

.btn-sm {
    padding: 8px 16px;
    font-size: 0.8rem;
}

.input-actions {
    display: flex;
    gap: 12px;
    margin-top: 20px;
}

/* Metrics Grid */
.metrics-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
    margin-bottom: 20px;
}

.metric-card {
    background: var(--bg-input);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 16px;
    transition: border-color 0.2s;
}

.metric-card:hover {
    border-color: var(--accent);
}

.metric-label {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: var(--text-muted);
    margin-bottom: 4px;
}

.metric-value {
    font-family: var(--font-mono);
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.metric-benchmark {
    font-size: 0.75rem;
    color: var(--text-muted);
}

.metric-benchmark.positive {
    color: var(--success);
}

.metric-benchmark.negative {
    color: var(--danger);
}

.metric-benchmark.neutral {
    color: var(--warning);
}

/* Export */
.export-actions {
    display: flex;
    justify-content: flex-end;
    margin-top: 16px;
}

/* Sliders */
.slider {
    width: 100%;
    height: 6px;
    -webkit-appearance: none;
    appearance: none;
    background: var(--bg-input);
    border-radius: 3px;
    outline: none;
    margin-top: 8px;
}

.slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 20px;
    height: 20px;
    background: var(--accent);
    border-radius: 50%;
    cursor: pointer;
    box-shadow: 0 2px 8px var(--accent-glow);
}

.slider::-moz-range-thumb {
    width: 20px;
    height: 20px;
    background: var(--accent);
    border-radius: 50%;
    cursor: pointer;
    border: none;
    box-shadow: 0 2px 8px var(--accent-glow);
}

.slider-value {
    display: inline-block;
    font-family: var(--font-mono);
    font-size: 0.875rem;
    color: var(--accent);
    font-weight: 600;
    margin-top: 4px;
}

/* Scenario Results */
.scenario-results {
    min-height: 200px;
}

.scenario-results .placeholder-text {
    color: var(--text-muted);
    text-align: center;
    padding-top: 60px;
}

.scenario-metric {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 0;
    border-bottom: 1px solid var(--border);
}

.scenario-metric:last-child {
    border-bottom: none;
}

.scenario-metric-label {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.scenario-metric-values {
    display: flex;
    align-items: center;
    gap: 12px;
    font-family: var(--font-mono);
}

.scenario-old {
    color: var(--text-muted);
    text-decoration: line-through;
    font-size: 0.875rem;
}

.scenario-new {
    color: var(--accent);
    font-weight: 600;
}

.scenario-change {
    font-size: 0.75rem;
    padding: 2px 8px;
    border-radius: 12px;
}

.scenario-change.positive {
    background: rgba(34, 197, 94, 0.15);
    color: var(--success);
}

.scenario-change.negative {
    background: rgba(239, 68, 68, 0.15);
    color: var(--danger);
}

/* Cohort Table */
.cohort-inputs {
    display: flex;
    gap: 16px;
    align-items: flex-end;
    margin-bottom: 24px;
    flex-wrap: wrap;
}

.cohort-inputs .input-group {
    flex: 1;
    min-width: 150px;
    margin-bottom: 0;
}

.cohort-table-wrapper {
    overflow-x: auto;
}

.cohort-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.8rem;
}

.cohort-table th,
.cohort-table td {
    padding: 10px 12px;
    text-align: center;
    border: 1px solid var(--border);
}

.cohort-table th {
    background: var(--bg-input);
    font-weight: 600;
    color: var(--text-secondary);
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.cohort-table td {
    font-family: var(--font-mono);
    font-size: 0.8rem;
}

.cohort-cell {
    display: inline-block;
    padding: 4px 8px;
    border-radius: 4px;
    min-width: 50px;
}

/* History */
.history-list {
    max-height: 600px;
    overflow-y: auto;
}

.history-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px;
    background: var(--bg-input);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    margin-bottom: 12px;
    transition: border-color 0.2s;
}

.history-item:hover {
    border-color: var(--accent);
}

.history-date {
    font-size: 0.75rem;
    color: var(--text-muted);
    font-family: var(--font-mono);
}

.history-metrics {
    display: flex;
    gap: 24px;
    flex-wrap: wrap;
}

.history-metric {
    text-align: center;
}

.history-metric-label {
    font-size: 0.7rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.history-metric-value {
    font-family: var(--font-mono);
    font-size: 1rem;
    font-weight: 600;
}

.history-actions {
    display: flex;
    gap: 8px;
}

/* Ad Placeholder */
.ad-placeholder {
    padding: 40px;
    text-align: center;
    background: var(--bg-secondary);
    border: 2px dashed var(--border);
}

.ad-label {
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--text-muted);
    display: block;
    margin-bottom: 16px;
}

.ad-slot {
    min-height: 90px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-muted);
}

/* Footer */
.footer {
    border-top: 1px solid var(--border);
    padding: 24px 0;
    text-align: center;
    color: var(--text-muted);
    font-size: 0.875rem;
    margin-top: 48px;
}

/* Placeholder Text */
.placeholder-text {
    color: var(--text-muted);
    text-align: center;
    padding: 40px 20px;
}

/* Responsive */
@media (max-width: 1024px) {
    .grid-3 {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .grid-2,
    .grid-3 {
        grid-template-columns: 1fr;
    }

    .header .container {
        flex-direction: column;
    }

    .nav {
        width: 100%;
        overflow-x: auto;
    }

    .metrics-grid {
        grid-template-columns: 1fr;
    }

    .input-actions {
        flex-direction: column;
    }

    .input-actions .btn {
        width: 100%;
    }

    .history-item {
        flex-direction: column;
        gap: 12px;
        align-items: flex-start;
    }

    .history-metrics {
        width: 100%;
    }

    .cohort-inputs {
        flex-direction: column;
    }

    .cohort-inputs .input-group {
        width: 100%;
    }
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-primary);
}

::-webkit-scrollbar-thumb {
    background: var(--border);
    border-radius: 4px;
}

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

/* Chart containers */
canvas {
    max-height: 300px;
}