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

html, body {
    width: 100%;
    height: 100%;
    overflow: hidden;
    background: #0a0a1a;
    font-family: 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
    color: #fff;
    -webkit-tap-highlight-color: transparent;
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    user-select: none;
    touch-action: none;
}

#game-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
    z-index: 0;
}

#game-canvas {
    position: absolute;
    top: 0;
    left: 0;
    display: block;
    width: 100%;
    height: 100%;
    image-rendering: auto;
    z-index: 1;
    touch-action: none;
}

.hidden {
    display: none !important;
}

.screen {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 20;
    background: linear-gradient(180deg, #0d1b3e 0%, #1a1040 50%, #0a0a2a 100%);
}

.screen-content {
    text-align: center;
    max-width: 420px;
    width: 90%;
    padding: 30px 20px;
}

.screen-content.scrollable {
    max-height: 90vh;
    overflow-y: auto;
    scrollbar-width: thin;
    scrollbar-color: rgba(255,255,255,0.3) transparent;
    -webkit-overflow-scrolling: touch;
    touch-action: pan-y;
}

.screen-title {
    font-size: 2.2rem;
    font-weight: 900;
    letter-spacing: 3px;
    margin-bottom: 24px;
    text-shadow: 0 0 20px rgba(100, 200, 255, 0.5);
}

.gameover-title {
    color: #ff4757;
    text-shadow: 0 0 20px rgba(255, 71, 87, 0.5);
}