:root {
    --bg-app: #f4f4f4;
    --bg-canvas: #fafafa;
    --panel-bg: #ffffff;
    --text-color: #1a1a1a;
    --text-muted: #555;
    --text-inverse: #ffffff;
    --border-color: #cbd5e1;
    --readouts-bg: rgba(0, 0, 0, 0.04);
    --canvas-bg: #ffffff;
    --canvas-border: #cbd5e1;
    --canvas-grid: rgba(0, 0, 0, 0.12);
    --canvas-axis: #555;
    --los-color: rgba(0, 0, 0, 0.25);
    --ground-color: #888;
    --canon-color: #555;

    --accent-color: #16a34a; /* semantic - tir */
    --accent-hover: #22c55e;
    --secondary-color: #1d4ed8; /* semantic - trajectoire bleue */
    --danger-color: #dc2626; /* semantic - impact */
    --tree-color: #8B4513; /* saddle brown - natural */
    --foliage-color: #228B22; /* forest green - natural */
    --monkey-color: #795548; /* brown - natural */
    --monkey-face: #D7CCC8; /* light beige - natural */

    --font-main: 'Inter', sans-serif;
    --font-mono: 'Roboto Mono', monospace;
}

:root[data-theme="dark"] {
    --bg-app: #1a1a1a;
    --bg-canvas: #1a1a1a;
    --panel-bg: #2d2d2d;
    --text-color: #e0e0e0;
    --text-muted: #aaa;
    --text-inverse: #0f172a;
    --border-color: #444;
    --readouts-bg: rgba(0, 0, 0, 0.2);
    --canvas-bg: #000;
    --canvas-border: #444;
    --canvas-grid: #333;
    --canvas-axis: #666;
    --los-color: rgba(255, 255, 255, 0.3);
    --ground-color: #555;
    --canon-color: #aaa;

    --accent-color: #4CAF50;
    --accent-hover: #45a049;
    --secondary-color: #2196F3;
    --danger-color: #f44336;
    --tree-color: #8B4513;
    --foliage-color: #228B22;
    --monkey-color: #795548;
    --monkey-face: #D7CCC8;
}

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

body {
    font-family: var(--font-main);
    background-color: var(--bg-app);
    color: var(--text-color);
    height: 100vh;
    display: flex;
    flex-direction: column;
    transition: background-color 0.2s ease, color 0.2s ease;
}

.app-container {
    display: flex;
    flex-direction: column;
    height: 100%;
    max-width: 1400px;
    margin: 0 auto;
    width: 100%;
    padding: 20px;
}

header {
    margin-bottom: 20px;
    text-align: center;
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 20px;
}

header h1 {
    font-weight: 600;
    font-size: 1.5rem;
    color: var(--text-color);
    letter-spacing: 0.05em;
    text-transform: uppercase;
}

main {
    display: flex;
    flex: 1;
    gap: 20px;
    overflow: hidden; /* Prevent scrolling if possible */
}

@media (max-width: 800px) {
    main {
        flex-direction: column;
        overflow-y: auto;
    }
}

.canvas-container {
    flex: 3;
    background-color: var(--canvas-bg);
    border: 1px solid var(--canvas-border);
    border-radius: 8px;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background-color 0.2s ease, border-color 0.2s ease;
}

canvas {
    width: 100%;
    height: 100%;
    display: block;
}

#collision-message {
    position: absolute;
    top: 20px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--danger-color);
    padding: 10px 20px;
    border-radius: 4px;
    font-weight: bold;
    font-size: 1.2rem;
    color: white;
    pointer-events: none;
    transition: opacity 0.3s;
}

.hidden {
    opacity: 0;
}

.controls {
    flex: 1;
    background-color: var(--panel-bg);
    padding: 20px;
    border-radius: 8px;
    display: flex;
    flex-direction: column;
    gap: 20px;
    min-width: 300px;
    overflow-y: auto;
    transition: background-color 0.2s ease;
}

.control-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.control-group label {
    font-size: 0.9rem;
    display: flex;
    flex-direction: column;
    gap: 5px;
    color: var(--text-color);
}

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

.checkbox-group label {
    flex-direction: row;
    align-items: center;
    gap: 10px;
    cursor: pointer;
}

.readouts {
    background: var(--readouts-bg);
    padding: 15px;
    border-radius: 4px;
    font-family: var(--font-mono);
    font-size: 0.9rem;
    transition: background-color 0.2s ease;
}

.buttons {
    margin-top: auto;
    display: flex;
    gap: 10px;
}

button {
    flex: 1;
    padding: 12px;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-weight: 600;
    font-size: 1rem;
    transition: filter 0.2s;
}

button:hover:not(:disabled) {
    filter: brightness(1.1);
}

button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.primary-btn {
    background-color: var(--accent-color);
    color: white;
}

.secondary-btn {
    background-color: var(--secondary-color);
    color: white;
}

.theme-toggle {
    background-color: var(--bg-elevated, var(--panel-bg));
    color: var(--text-color);
    border: 1px solid var(--border-color);
    padding: 8px 14px;
    font-family: var(--font-main);
    font-size: 0.8rem;
    cursor: pointer;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    border-radius: 4px;
    transition: all 0.2s;
    flex: none;
}

.theme-toggle:hover {
    background: var(--text-color);
    color: var(--text-inverse);
}