:root {
    --bg-color: #1a1a1a;
    --panel-bg: #2a2a2a;
    --text-color: #e0e0e0;
    --accent-color: #4a9eff;
    --border-color: #444;
}

body {
    margin: 0;
    padding: 0;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    height: 100vh;
    overflow: hidden;
}

#app {
    display: flex;
    height: 100%;
}

#canvas-container {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: #000;
    overflow: hidden;
}

canvas {
    width: 100%;
    height: 100%;
    object-fit: contain;
    image-rendering: pixelated;
    /* Important for grid visualization */
    box-shadow: 0 0 20px rgba(0, 0, 0, 0.5);
}

#controls {
    width: 320px;
    background-color: var(--panel-bg);
    padding: 6px;
    border-left: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    gap: 6px;
    overflow-y: auto;
}

h1 {
    margin: 0 0 10px 0;
    font-size: 1.5rem;
    color: var(--accent-color);
}

a {
    color: var(--accent-color);
    text-decoration: none;
}

a:hover {
    color: #8bc4ff;
    text-decoration: underline;
}

.control-supergroup {
    border: 1px solid var(--border-color);
    border-radius: 4px;
    background-color: rgba(0, 0, 0, 0.2);
    overflow: hidden;
}

.control-supergroup-header {
    padding: 8px;
    background-color: #333;
    cursor: pointer;
    font-size: 0.85rem;
    font-weight: bold;
    display: flex;
    justify-content: space-between;
    align-items: center;
    user-select: none;
    color: var(--text-color);
}

.control-supergroup-header:hover {
    background-color: #3a3a3a;
}

.control-supergroup-content {
    padding: 8px;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.control-supergroup.collapsed .control-supergroup-content {
    display: none;
}

.control-supergroup-header::after {
    content: '▼';
    font-size: 0.7em;
    opacity: 0.7;
}

.control-supergroup.collapsed .control-supergroup-header::after {
    content: '▶';
}

.control-group {
    display: flex;
    flex-direction: row;
    align-items: center;
    gap: 8px;
}

label {
    font-size: 0.8rem;
    font-weight: 600;
    color: #aaa;
    flex: 0 0 160px; /* Fixed width for labels */
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

input[type="range"] {
    flex: 1;
    min-width: 0; /* Allow shrinking */
}

.value-display {
    font-size: 0.78rem;
    text-align: right;
    color: var(--accent-color);
    flex: 0 0 40px; /* Fixed width for values */
}

.button-row {
    display: flex;
    gap: 10px;
}

button {
    flex: 1;
    padding: 8px;
    background-color: #3a3a3a;
    border: 1px solid var(--border-color);
    color: white;
    border-radius: 4px;
    cursor: pointer;
    transition: background-color 0.2s;
}

button:hover {
    background-color: #4a4a4a;
}

button:active {
    background-color: #2a2a2a;
}

button.active {
    background-color: var(--accent-color);
    color: #fff;
    border-color: var(--accent-color);
}

select {
    padding: 8px;
    background-color: #3a3a3a;
    border: 1px solid var(--border-color);
    color: white;
    border-radius: 4px;
}

.stats {
    margin-top: auto;
    padding-top: 12px;
    border-top: 1px solid var(--border-color);
    font-family: monospace;
    font-size: 0.9rem;
    color: #888;
}

.stats p {
    margin: 5px 0;
}

/* On-screen compact status bar (running/paused + key params) */
.status-bar {
    position: fixed;
    top: 12px;
    right: 12px;
    background: rgba(20,20,20,0.75);
    color: var(--text-color);
    padding: 6px 10px;
    border-radius: 6px;
    font-size: 0.85rem;
    z-index: 1000;
    box-shadow: 0 2px 8px rgba(0,0,0,0.5);
    pointer-events: none;
    min-width: 220px;
    font-family: monospace;
}

/* Splash Screen */
.splash-screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.4);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 2000;
    color: white;
    font-family: sans-serif;
}

.splash-content {
    background: #222;
    padding: 2rem;
    border-radius: 8px; 
    max-width: 500px;
    text-align: center;
    box-shadow: 0 4px 20px rgba(0,0,0,0.5);
    border: 1px solid #444;
}

.splash-content h2 {
    margin-top: 0;
    color: var(--accent-color);
}

.splash-content ul {
    text-align: left;
    margin: 1.5rem 0;
    padding-left: 2rem;
    color: #ccc;
}

.splash-content li {
    margin-bottom: 0.5rem;
}

.splash-content button {
    background: var(--accent-color);
    color: white;
    border: none;
    padding: 10px 20px;
    font-size: 1.1rem;
    border-radius: 4px;
    cursor: pointer;
    margin-top: 1rem;
}

.splash-content button:hover {
    background: #3a8eef;
}

/* Popup Panel */
.popup-panel {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background-color: var(--panel-bg);
    border: 1px solid var(--border-color);
    padding: 20px;
    border-radius: 8px;
    z-index: 1500;
    box-shadow: 0 0 20px rgba(0,0,0,0.5);
    min-width: 350px;
    color: var(--text-color);
}

.popup-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 10px;
}

.popup-header h2 {
    margin: 0;
    font-size: 1.2rem;
    color: var(--accent-color);
}

.popup-panel .control-group {
    margin-bottom: 12px;
}