:root {
    --bg: #0f1419;
    --panel: #1a2332;
    --text: #e8eef6;
    --muted: #9aa8b8;
    --line: #2a3a4e;
    --accent: #5b9fd4;
    --canvas: #121820;
}

* { box-sizing: border-box; }

[hidden] { display: none !important; }

body {
    margin: 0;
    min-height: 100vh;
    color: var(--text);
    background:
        radial-gradient(1000px 480px at 0% -10%, #1d3a55 0%, transparent 55%),
        var(--bg);
    font-family: "SF Pro Text", "PingFang SC", "Hiragino Sans GB", sans-serif;
    line-height: 1.5;
    color-scheme: dark;
}

a { color: #7eb6e8; }

.wrap {
    max-width: 1180px;
    margin: 0 auto;
    padding: 28px 20px 48px;
}

header h1 {
    margin: 8px 0 4px;
    font-size: 28px;
    font-weight: 600;
}

.sub { margin: 0; color: var(--muted); }

.layout {
    display: grid;
    grid-template-columns: minmax(280px, 1fr) 332px;
    gap: 20px;
    align-items: start;
    margin-top: 22px;
}

.stage { width: 100%; max-width: 780px; }

canvas {
    width: 100%;
    aspect-ratio: 1;
    display: block;
    background: var(--canvas);
    border-radius: 12px;
    border: 1px solid var(--line);
    cursor: grab;
    touch-action: none;
}

canvas.dragging { cursor: grabbing; }

.status {
    min-height: 3.2em;
    margin: 10px 2px 0;
    color: var(--muted);
    font-size: 13px;
    font-variant-numeric: tabular-nums;
}

.panel {
    background: var(--panel);
    border: 1px solid var(--line);
    border-radius: 12px;
    padding: 14px 14px 8px;
    position: sticky;
    top: 16px;
    max-height: calc(100vh - 32px);
    overflow: auto;
}

.panel h2 {
    margin: 4px 0 12px;
    font-size: 16px;
}

.field { margin-bottom: 12px; }

.label-row {
    display: flex;
    justify-content: space-between;
    gap: 12px;
    align-items: baseline;
    margin-bottom: 6px;
    font-size: 13px;
}

output {
    color: var(--accent);
    font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
    font-size: 12px;
}

.hint {
    margin: 6px 0 0;
    color: var(--muted);
    font-size: 12px;
}

input[type="range"] {
    width: 100%;
    accent-color: var(--accent);
}

select, button {
    font: inherit;
    color: var(--text);
}

select {
    width: 100%;
    background: #121a24;
    border: 1px solid var(--line);
    border-radius: 8px;
    padding: 7px 8px;
}

.segment {
    display: flex;
    gap: 6px;
}

.segment label {
    position: relative;
    flex: 1;
    text-align: center;
    border: 1px solid var(--line);
    border-radius: 8px;
    padding: 7px 4px;
    font-size: 13px;
    cursor: pointer;
}

.segment label.on,
.segment label:has(input:checked) {
    border-color: var(--accent);
    background: #1d3a55;
}

.segment input {
    position: absolute;
    inset: 0;
    margin: 0;
    opacity: 0;
    cursor: pointer;
}

.segment label:focus-within { outline: 2px solid #7eb6e8; }

.presets, .button-row {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
}

button {
    background: #121a24;
    border: 1px solid var(--line);
    border-radius: 8px;
    padding: 7px 10px;
    cursor: pointer;
}

button:hover { border-color: var(--accent); }

.check {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 14px;
}

.notes {
    margin-top: 8px;
    padding-top: 8px;
    border-top: 1px solid var(--line);
}

.notes h2 { margin-bottom: 8px; }

.notes ul {
    margin: 0 0 12px;
    padding-left: 18px;
    color: var(--muted);
    font-size: 13px;
}

kbd {
    font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
    font-size: 12px;
    border: 1px solid #3a4c62;
    border-bottom-width: 2px;
    border-radius: 4px;
    padding: 0 5px;
    background: #121a24;
    color: var(--text);
}

@media (max-width: 900px) {
    .layout { grid-template-columns: 1fr; }
    .panel {
        position: static;
        max-height: none;
    }
}