:root{
    /* light theme colors */
    --bg:#f7fafc;             /* overall background */
    --panel:#f9fafb;          /* sidebar background */
    --ink:#111827;            /* text */
    --muted:#4b5563;          /* muted text */
    --accent:#2563eb;         /* blue */
    --accent-2:#7c3aed;       /* purple */
    --accent-3:#10b981;       /* green */
    --accent-4:#f59e0b;       /* orange */
    --danger:#dc2626;         /* red */
    --ghost:#e5e7eb;          /* hover gray */
    --ring:#d1d5db;           /* borders */
    --chip:#ffffff;           /* button fill */
}

* { box-sizing: border-box; }
html, body {
    height:100%;
    margin:0;
    background:var(--bg);
    color:var(--ink);
    font:14px/1.4 system-ui, -apple-system, Segoe UI, Roboto, Ubuntu, Cantarell, "Helvetica Neue", Arial, "Noto Sans", sans-serif;
}

#app {
    display:grid;
    grid-template-columns: 320px 1fr;
    height:100vh;
}

/* side panel */
aside#controls {
    padding:16px 14px 18px;
    background:var(--panel);
    border-right:1px solid var(--ring);
    overflow:auto;
}
aside h1 {
    margin:0 0 12px;
    font-size:18px;
    font-weight:700;
    letter-spacing:.2px;
}

.group {
    margin:14px 0 18px;
    padding:12px;
    background:#ffffff;
    border:1px solid var(--ring);
    border-radius:12px;
}
.group-title {
    font-weight:700;
    font-size:12px;
    text-transform:uppercase;
    letter-spacing:.14em;
    color:var(--muted);
    margin-bottom:8px;
}

.radio, .checkbox {
    display:flex;
    align-items:center;
    gap:8px;
    margin:6px 0;
    cursor:pointer;
}
.radio input, .checkbox input { accent-color: var(--accent); }
.radio-row { display:flex; gap:16px; }
.group-icons .checkbox .icon { margin-left:2px; }

/* icons */
#controls img.icon,
#controls img {
    width:22px;
    height:22px;
    object-fit:contain;
    display:inline-block;
}

/* sliders */
.slider-row { display:grid; grid-template-columns:1fr; gap:6px; margin:8px 0; }
.slider-row label { color:var(--muted); font-size:12px; }
.slider-row input[type="range"] { width:100%; }
.slider-values { font-size:12px; color:var(--muted); }

.toggle-row { margin:6px 0 8px; }

/* timeline area */
#timeline {
    display:grid;
    grid-template-columns:auto 1fr auto auto;
    gap:8px;
    align-items:center;
}
#timeSlider { width:100%; }
#timeLabel { margin-top:6px; font-size:12px; color:var(--muted); }

/* buttons */
button {
    display:inline-flex;
    align-items:center;
    justify-content:center;
    padding:8px 10px;
    border-radius:10px;
    border:1px solid var(--ring);
    background:var(--chip);
    color:var(--ink);
    cursor:pointer;
    font-weight:600;
}
button.primary { background:#e0e7ff; border-color:#c7d2fe; }
button.ghost { background:transparent; border-color:var(--ring); }
button:focus { outline:2px solid var(--accent); outline-offset:2px; }
button[disabled]{ opacity:.5; cursor:not-allowed; }

.map-buttons{ display:flex; gap:8px; }

/* map container */
main#viz { position:relative; min-height:70vh; background:#e0f2fe; } /* light ocean blue */
#map { width:100%; height:100%; display:block; }

/* tooltip (light version) */
#tooltip {
    position:absolute;
    pointer-events:none;
    background:#ffffff;
    border:1px solid var(--ring);
    padding:10px 12px;
    border-radius:10px;
    min-width:220px;
    max-width:320px;
    box-shadow:0 4px 16px rgba(0,0,0,.1);
    transform:translate(-50%, calc(-100% - 12px));
    color:var(--ink);
}
#tooltip.hidden { display:none; }
#tooltip h3 { margin:0 0 6px; font-size:14px; color:var(--ink); }
#tooltip .meta { color:var(--muted); font-size:12px; margin-bottom:6px; }
#tooltip .bar-wrap { margin-top:8px; }
#tooltip .bar {
    height:8px;
    background:linear-gradient(90deg, var(--accent), var(--accent-2));
    border-radius:6px;
}
#tooltip .bar-bg {
    height:8px;
    width:100%;
    background:#f3f4f6;
    border-radius:6px;
    border:1px solid var(--ring);
}

/* quake hover */
.quake:hover { stroke:#000; stroke-width:1.2px; }

/* legend */
.legend {
    position:absolute;
    right:12px;
    bottom:12px;
    background:#ffffff;
    border:1px solid var(--ring);
    padding:10px 12px;
    border-radius:12px;
    color:var(--ink);
}
.legend .row {
    display:flex;
    gap:10px;
    align-items:center;
    margin:6px 0;
}
.legend .swatch {
    width:14px;
    height:14px;
    border-radius:3px;
    border:1px solid #9ca3af;
}
.swatch.mag { background:#1b9e77; }
.swatch.cdi { background:#d95f02; }
.swatch.mmi { background:#7570b3; }
.swatch.sig { background:#e7298a; }

/* badge */
.badge {
    display:inline-block;
    padding:2px 6px;
    border-radius:6px;
    background:#f3f4f6;
    border:1px solid var(--ring);
    color:var(--ink);
    font-size:11px;
}

/* responsive */
@media (max-width:980px){
    #app{ grid-template-columns:1fr; }
    aside#controls{ order:2; }
    main#viz{ order:1; height:60vh; }
}