:root {
    --bg-primary: #0a0e17;
    --bg-secondary: #111827;
    --bg-tertiary: #1a2235;
    --text-primary: #e2e8f0;
    --text-secondary: #94a3b8;
    --accent: #38bdf8;
    --accent-dim: #0c4a6e;
    --border: #1e293b;
    --success: #34d399;
    --warning: #fbbf24;
}

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

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

header {
    text-align: center;
    padding: 1.5rem 1rem 1rem;
    border-bottom: 1px solid var(--border);
}

header h1 {
    font-size: 1.6rem;
    font-weight: 600;
    letter-spacing: 0.02em;
}

.subtitle {
    color: var(--text-secondary);
    font-size: 0.85rem;
    margin-top: 0.25rem;
}

main {
    max-width: 1100px;
    margin: 0 auto;
    padding: 1.25rem 1rem;
}

/* Controls */
.controls {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    align-items: flex-end;
    padding: 1rem;
    background: var(--bg-secondary);
    border-radius: 8px;
    border: 1px solid var(--border);
    margin-bottom: 0.75rem;
}

.control-group {
    display: flex;
    flex-direction: column;
    gap: 0.3rem;
}

.control-group label {
    font-size: 0.75rem;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

select, input[type="number"] {
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    color: var(--text-primary);
    padding: 0.5rem 0.6rem;
    border-radius: 6px;
    font-size: 0.85rem;
    min-width: 140px;
}

select:focus, input:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 2px var(--accent-dim);
}

#plot-btn {
    background: var(--accent);
    color: var(--bg-primary);
    border: none;
    padding: 0.5rem 1.5rem;
    border-radius: 6px;
    font-size: 0.85rem;
    font-weight: 600;
    cursor: pointer;
    transition: opacity 0.15s;
}

#plot-btn:hover {
    opacity: 0.85;
}

/* Presets */
.presets {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    align-items: center;
    margin-bottom: 0.75rem;
}

.presets-label {
    font-size: 0.75rem;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.preset-btn {
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    color: var(--text-primary);
    padding: 0.35rem 0.75rem;
    border-radius: 6px;
    font-size: 0.78rem;
    cursor: pointer;
    transition: border-color 0.15s, background 0.15s;
}

.preset-btn:hover {
    border-color: var(--accent);
    background: var(--accent-dim);
}

.preset-btn.preset-active {
    border-color: var(--accent);
    background: var(--accent-dim);
    color: var(--accent);
}

/* Scale controls */
.scale-controls {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    align-items: center;
    padding: 0.5rem 1rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    margin-bottom: 0.75rem;
    font-size: 0.78rem;
}

.scale-lock {
    display: flex;
    align-items: center;
    gap: 0.3rem;
    color: var(--text-secondary);
    cursor: pointer;
}

.scale-lock input {
    accent-color: var(--accent);
    cursor: pointer;
}

.scale-param {
    display: flex;
    align-items: center;
    gap: 0.25rem;
    color: var(--text-secondary);
}

.scale-input {
    width: 80px;
    min-width: 80px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    color: var(--text-primary);
    padding: 0.3rem 0.4rem;
    border-radius: 4px;
    font-size: 0.78rem;
    font-family: 'SF Mono', 'Fira Code', monospace;
}

.scale-input:focus {
    outline: none;
    border-color: var(--accent);
}

.scale-reset-btn {
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    color: var(--text-secondary);
    padding: 0.3rem 0.6rem;
    border-radius: 4px;
    font-size: 0.75rem;
    cursor: pointer;
}

.scale-reset-btn:hover {
    border-color: var(--accent);
    color: var(--text-primary);
}

/* Layers */
.layers-panel {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 0.75rem 1rem;
    margin-bottom: 1rem;
}

.layers-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.5rem;
}

.layers-header h2 {
    font-size: 0.85rem;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

#add-layer-btn {
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    color: var(--accent);
    padding: 0.3rem 0.7rem;
    border-radius: 6px;
    font-size: 0.78rem;
    cursor: pointer;
    transition: border-color 0.15s;
}

#add-layer-btn:hover {
    border-color: var(--accent);
}

.layer-row {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 0.5rem 0.5rem 0.75rem;
    border-left: 3px solid var(--accent);
    border-radius: 0 6px 6px 0;
    background: var(--bg-tertiary);
    margin-bottom: 0.4rem;
}

.layer-row select {
    min-width: 80px;
    padding: 0.35rem 0.4rem;
    font-size: 0.8rem;
}

.layer-row .db-select {
    min-width: 70px;
}

.layer-toggle input {
    cursor: pointer;
    accent-color: var(--accent);
    width: 16px;
    height: 16px;
}

.layer-param {
    display: flex;
    align-items: center;
    gap: 0.2rem;
    font-size: 0.78rem;
    color: var(--text-secondary);
}

.layer-param input {
    width: 65px;
    min-width: 65px;
    padding: 0.3rem 0.35rem;
    font-size: 0.8rem;
    text-align: right;
}

.layer-color-picker {
    width: 28px;
    height: 28px;
    padding: 1px;
    border: 1px solid var(--border);
    border-radius: 4px;
    background: var(--bg-tertiary);
    cursor: pointer;
    flex-shrink: 0;
}

.layer-color-picker::-webkit-color-swatch-wrapper {
    padding: 1px;
}

.layer-color-picker::-webkit-color-swatch {
    border: none;
    border-radius: 2px;
}

.layer-remove {
    background: none;
    border: none;
    color: var(--text-secondary);
    font-size: 1.1rem;
    cursor: pointer;
    padding: 0 0.3rem;
    line-height: 1;
    transition: color 0.15s;
}

.layer-remove:hover {
    color: #f87171;
}

/* Export bar */
.export-bar {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 0.75rem;
}

.export-btn {
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    color: var(--text-primary);
    padding: 0.4rem 0.8rem;
    border-radius: 6px;
    font-size: 0.78rem;
    cursor: pointer;
    transition: border-color 0.15s, background 0.15s;
}

.export-btn:hover {
    border-color: var(--accent);
    background: var(--accent-dim);
}

/* Chart */
.chart-container {
    position: relative;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    overflow: hidden;
    margin-bottom: 1rem;
}

#spectrum-canvas {
    width: 100%;
    height: 420px;
    display: block;
}

.tooltip {
    display: none;
    position: absolute;
    background: var(--bg-tertiary);
    border: 1px solid var(--accent);
    border-radius: 6px;
    padding: 0.5rem 0.7rem;
    font-size: 0.78rem;
    color: var(--text-primary);
    pointer-events: none;
    white-space: nowrap;
    z-index: 10;
    line-height: 1.5;
}

/* Legend */
.legend {
    display: none;
    position: absolute;
    top: 8px;
    right: 12px;
    flex-wrap: wrap;
    gap: 0.6rem;
    padding: 0.4rem 0.6rem;
    background: rgba(17, 24, 39, 0.85);
    border: 1px solid var(--border);
    border-radius: 6px;
    font-size: 0.75rem;
}

.legend-item {
    display: flex;
    align-items: center;
    gap: 0.3rem;
    color: var(--text-primary);
}

.legend-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    flex-shrink: 0;
}

/* Info panel */
.info-panel {
    display: flex;
    gap: 1rem;
    margin-bottom: 1rem;
}

.stat {
    flex: 1;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 0.75rem 1rem;
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
}

.stat-label {
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-secondary);
}

.stat-value {
    font-size: 1rem;
    font-weight: 600;
    color: var(--accent);
}

/* Table */
.line-table-container {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 1rem;
    max-height: 300px;
    overflow-y: auto;
}

.line-table-container h2 {
    font-size: 0.95rem;
    margin-bottom: 0.75rem;
    color: var(--text-secondary);
}

#line-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.8rem;
}

#line-table th {
    text-align: left;
    padding: 0.4rem 0.6rem;
    border-bottom: 1px solid var(--border);
    color: var(--text-secondary);
    font-weight: 500;
    position: sticky;
    top: 0;
    background: var(--bg-secondary);
}

#line-table td {
    padding: 0.35rem 0.6rem;
    border-bottom: 1px solid var(--border);
    font-family: 'SF Mono', 'Fira Code', monospace;
}

#line-table tr:hover td {
    background: var(--bg-tertiary);
}

.line-table-container::-webkit-scrollbar {
    width: 6px;
}

.line-table-container::-webkit-scrollbar-track {
    background: var(--bg-secondary);
}

.line-table-container::-webkit-scrollbar-thumb {
    background: var(--border);
    border-radius: 3px;
}

@media (max-width: 700px) {
    .controls {
        flex-direction: column;
    }

    select, input[type="number"] {
        min-width: 100%;
    }

    .info-panel {
        flex-direction: column;
    }

    #spectrum-canvas {
        height: 280px;
    }

    .layer-row {
        flex-wrap: wrap;
    }

    .layer-param input {
        width: 55px;
        min-width: 55px;
    }
}