:root {
    --bg-color: #111;
    --grid-line: #222;
    --text-color: #eee;
    --accent-color: #0f0;
    --ui-bg: rgba(0, 0, 0, 0.8);
    --btn-bg: #333;
    --btn-active: #555;
    --font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

* {
    box-sizing: border-box;
    touch-action: none; /* Prevent default touch actions like scroll */
    user-select: none;
}

body {
    margin: 0;
    padding: 0;
    background-color: var(--bg-color);
    color: var(--text-color);
    font-family: var(--font-family);
    overflow: hidden; /* Prevent scrolling */
    height: 100vh; /* Fallback */
    height: 100dvh; /* Dynamic Viewport Height for Mobile */
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}

.app-container {
    display: flex;
    flex-direction: column;
    width: 100%;
    max-width: 600px;
    height: 100%;
    max-height: 900px;
    padding: 10px;
    
    /* iPhone Safe Area support */
    padding-top: max(10px, env(safe-area-inset-top));
    padding-bottom: max(10px, env(safe-area-inset-bottom));
    padding-left: max(10px, env(safe-area-inset-left));
    padding-right: max(10px, env(safe-area-inset-right));
}

/* Header */
.game-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 0;
    font-size: 1.2rem;
    font-weight: bold;
}

.score-board {
    display: flex;
    gap: 15px;
}

.score-item span {
    color: var(--accent-color);
}

.settings-bar {
    display: flex;
    gap: 5px;
    align-items: center;
}

.separator {
    width: 1px;
    height: 20px;
    background: #444;
    margin: 0 5px;
}

.color-control {
    position: relative;
    width: 28px;
    height: 28px;
    border-radius: 50%;
    overflow: hidden;
    border: 2px solid #444;
    cursor: pointer;
    transition: transform 0.2s, border-color 0.2s;
}

.color-control:hover {
    transform: scale(1.1);
    border-color: #fff;
}

.color-control input[type="color"] {
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    padding: 0;
    margin: 0;
    border: none;
    cursor: pointer;
    appearance: none;
}

.icon-btn {
    background: none;
    border: 1px solid #444;
    border-radius: 4px;
    color: #fff;
    cursor: pointer;
    font-size: 1.2rem;
    padding: 5px 8px;
    transition: background 0.2s;
}

.icon-btn:hover {
    background: #333;
}

.icon-btn.active {
    border-color: var(--accent-color);
    color: var(--accent-color);
}

/* Viewport & Canvas */
.game-viewport {
    position: relative;
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
    background: #000;
    border: 2px solid #333;
    border-radius: 8px;
    overflow: hidden;
    margin-bottom: 10px;
}

canvas {
    display: block;
    width: 100%;
    height: 100%;
    object-fit: contain;
}

/* Overlay */
.overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.85);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    z-index: 10;
    transition: opacity 0.3s;
}

.overlay.hidden {
    opacity: 0;
    pointer-events: none;
}

.overlay h1 {
    font-size: 3rem;
    margin: 0 0 10px 0;
    color: var(--accent-color);
    text-shadow: 0 0 10px var(--accent-color);
}

.overlay p {
    font-size: 1.2rem;
    margin-bottom: 30px;
}

.big-btn {
    padding: 15px 40px;
    font-size: 1.5rem;
    background: var(--accent-color);
    color: #000;
    border: none;
    border-radius: 50px;
    cursor: pointer;
    font-weight: bold;
    box-shadow: 0 0 15px var(--accent-color);
    transition: transform 0.1s;
}

.big-btn:active {
    transform: scale(0.95);
}

.controls-hint {
    margin-top: 20px;
    color: #888;
    font-size: 0.9rem;
}

/* D-Pad */
.d-pad {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
    padding-bottom: 20px;
}

.d-pad-row {
    display: flex;
    gap: 20px;
}

.d-btn {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    color: #fff;
    font-size: 1.5rem;
    display: flex;
    justify-content: center;
    align-items: center;
    cursor: pointer;
    -webkit-tap-highlight-color: transparent;
}

.d-btn:active {
    background: rgba(255, 255, 255, 0.3);
}

/* Responsive Utilities */
.mobile-only { display: none; }
.desktop-only { display: block; }

@media (max-width: 768px) {
    .mobile-only { display: flex; }
    .desktop-only { display: none; }
    
    .game-viewport {
        border-width: 1px;
    }
    
    .overlay h1 { font-size: 2.5rem; }
}

@media (hover: none) and (pointer: coarse) {
    /* Touch device specific */
    .mobile-only { display: flex; }
    .desktop-only { display: none; }
}