/* 画面全体に広がる */
html, body {
    width: 100%;
    height: 100%;
    margin: 0;
    padding: 0;
    overflow: hidden;
}

/* canvasを画面全体に敷く */
canvas {
    display: block;
    margin: 0;
    padding: 0;
    cursor: crosshair;
    touch-action: none;
}

/* controls */
.controls {
    position: fixed;
    right: 0;
    top: 0;
    height: 100%;
    width: 280px;
    z-index: 80;
    background: rgba(255,255,255,0.98);
    color: #111;
    padding: 16px;
    font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial;
    font-size: 13px;
    display: flex;
    flex-direction: column;
    gap: 12px;
    align-items: stretch;
    box-shadow: -8px 0 24px rgba(0,0,0,0.12);
    transform: translateX(100%);
    transition: transform 280ms ease;
    border-left: 1px solid rgba(0,0,0,0.04);
}
.controls label { display:flex; gap:6px; align-items:center; }
.controls input[type=range]{ width:160px; }
.controls select { padding: 4px 6px; font-family: system-ui, -apple-system, "Segoe UI", Roboto; font-size: 12px; }

body.dark .controls { background: rgba(20,20,20,0.92); color: #eee; }
/* canvas background */
.canvas { background: #fff; }
body.dark .canvas { background: #111; }

/* Toggle button for small screens */
.controls-toggle {
    display: block;
    position: fixed;
    right: 12px;
    top: 12px;
    z-index: 90;
    background: rgba(255,255,255,0.95);
    border: none;
    padding: 8px 10px;
    border-radius: 8px;
    font-size: 18px;
    line-height: 1;
    cursor: pointer;
    box-shadow: 0 2px 6px rgba(0,0,0,0.12);
}
body.dark .controls-toggle { background: rgba(30,30,30,0.95); color: #fff; }

/* top-level buttons (pause, clear, step, randomize) */
.top-btn {
    display: block;
    position: fixed;
    top: 12px;
    z-index: 90;
    background: rgba(255,255,255,0.95);
    border: none;
    padding: 8px 10px;
    border-radius: 8px;
    font-size: 13px;
    line-height: 1;
    cursor: pointer;
    box-shadow: 0 2px 6px rgba(0,0,0,0.08);
}
/* Position buttons horizontally */
#pauseToggle { left: 12px; }
#clearBtn { left: 60px; }
#stepBtn { left: 108px; }
#randomize { left: 156px; }
body.dark .top-btn { background: rgba(30,30,30,0.95); color: #fff; }

@media (max-width: 800px) {
    .controls { width: 84%; max-width: 320px; }
    .controls input[type=range]{ width: 100%; }
}

/* controls は body.controls-visible が付くと表示される（PC/モバイル共通） */
body.controls-visible .controls { transform: translateX(0); }

/* controls-toggle は常に表示（ハンバーガー） */
.controls-toggle { display: block; }

/* フェード（非アクティブ時）: トップのハンバーガーと同位ボタンのみ薄くする */
body.controls-faded .controls-toggle,
body.controls-faded .top-btn {
    opacity: 0.12;
    pointer-events: auto;
    transition: opacity 300ms ease;
}

/* controls-visible のときはトグルを隠す（重なりを避ける） */
body.controls-visible .controls-toggle { display: none; }

/* ホバーで復活 */
.controls:hover { opacity: 1 !important; pointer-events: auto !important; }
.controls-toggle:hover { opacity: 1 !important; }

/* screen-reader helper */
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0; }