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

body {
    font-family: 'Courier New', monospace;
    background: #0a0a0a;
    color: #fff;
    overflow: hidden;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
}

#game-container {
    position: relative;
    width: 800px;
    height: 600px;
    background: #1a1a1a;
    border: 2px solid #333;
    box-shadow: 0 0 50px rgba(0, 0, 0, 0.8), inset 0 0 100px rgba(0, 0, 0, 0.5);
}

#game-canvas {
    display: block;
    width: 100%;
    height: 100%;
    background: #0f0f0f;
}

/* UI Overlay */
#ui-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 10;
}

#top-ui {
    display: flex;
    justify-content: space-between;
    padding: 15px 20px;
    background: linear-gradient(to bottom, rgba(0, 0, 0, 0.8), transparent);
    font-size: 14px;
    font-weight: bold;
    text-shadow: 0 0 5px rgba(255, 0, 0, 0.5);
}

#top-ui > div {
    background: rgba(0, 0, 0, 0.6);
    padding: 5px 10px;
    border: 1px solid #333;
    border-radius: 3px;
}

#hp-value {
    color: #00ff00;
    transition: color 0.3s;
}

#score-value {
    color: #ffaa00;
}

/* Gravity Indicator */
#gravity-indicator {
    position: absolute;
    bottom: 60px;
    right: 20px;
    width: 100px;
    height: 100px;
}

#dash-indicator {
    position: absolute;
    bottom: 20px;
    right: 20px;
    width: 100px;
}

.arrow-container {
    position: relative;
    width: 100%;
    height: 100%;
}

.arrow {
    position: absolute;
    width: 0;
    height: 0;
    border: 15px solid transparent;
    opacity: 0.3;
    transition: opacity 0.2s, transform 0.2s;
}

.arrow.active {
    opacity: 1;
    filter: drop-shadow(0 0 8px #ff3333);
    animation: pulse 1s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.6; }
}

.arrow.up {
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    border-bottom-color: #ff3333;
    border-top: none;
}

.arrow.down {
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    border-top-color: #ff3333;
    border-bottom: none;
}

.arrow.left {
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    border-right-color: #ff3333;
    border-left: none;
}

.arrow.right {
    right: 0;
    top: 50%;
    transform: translateY(-50%);
    border-left-color: #ff3333;
    border-right: none;
}

.cooldown-label {
    font-size: 10px;
    text-align: center;
    color: #aaa;
    margin-bottom: 3px;
}

.cooldown-bar {
    width: 100%;
    height: 8px;
    background: rgba(50, 50, 50, 0.8);
    border: 1px solid #333;
    border-radius: 4px;
    overflow: hidden;
    position: relative;
}

.cooldown-bar-fill {
    height: 100%;
    background: linear-gradient(to right, #00ff00, #00cc00);
    transition: width 0.05s linear;
    box-shadow: 0 0 8px rgba(0, 255, 0, 0.5);
}

.cooldown-bar-fill.charging {
    background: linear-gradient(to right, #ffaa00, #ff6600);
    box-shadow: 0 0 8px rgba(255, 170, 0, 0.5);
}

/* Screens */
.screen {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    background: rgba(0, 0, 0, 0.95);
    z-index: 100;
    animation: fadeIn 0.5s;
}

.screen.hidden {
    display: none;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.screen h1 {
    font-size: 48px;
    margin-bottom: 20px;
    text-shadow: 0 0 20px #ff3333, 0 0 40px #ff0000;
    letter-spacing: 5px;
    animation: glow 2s infinite;
}

@keyframes glow {
    0%, 100% { text-shadow: 0 0 20px #ff3333, 0 0 40px #ff0000; }
    50% { text-shadow: 0 0 30px #ff6666, 0 0 60px #ff3333; }
}

.subtitle {
    font-size: 18px;
    margin-bottom: 10px;
    color: #aaa;
}

.version {
    font-size: 14px;
    margin-bottom: 20px;
    color: #666;
}

.controls-info {
    margin-bottom: 20px;
    text-align: center;
    line-height: 1.8;
}

.controls-info p {
    margin: 5px 0;
}

.difficulty-selector {
    margin-bottom: 20px;
    text-align: center;
}

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

.difficulty-btn {
    padding: 10px 20px;
    font-family: 'Courier New', monospace;
    font-size: 14px;
    font-weight: bold;
    background: rgba(50, 50, 50, 0.8);
    color: #aaa;
    border: 2px solid #555;
    border-radius: 5px;
    cursor: pointer;
    transition: all 0.2s;
    pointer-events: auto;
}

.difficulty-btn:hover {
    background: rgba(70, 70, 70, 0.8);
    border-color: #777;
}

.difficulty-btn.selected {
    background: linear-gradient(to bottom, #ff3333, #cc0000);
    color: #fff;
    border-color: #ff6666;
    box-shadow: 0 0 15px rgba(255, 51, 51, 0.5);
}

.features-info {
    margin-bottom: 20px;
    text-align: left;
    font-size: 13px;
}

.features-info ul {
    list-style-position: inside;
    color: #aaa;
    line-height: 1.6;
}

.features-info strong {
    color: #fff;
}

.result {
    font-size: 24px;
    margin: 10px 0;
    color: #ffaa00;
}

.game-button {
    padding: 15px 40px;
    font-size: 20px;
    font-family: 'Courier New', monospace;
    font-weight: bold;
    background: linear-gradient(to bottom, #ff3333, #cc0000);
    color: #fff;
    border: 2px solid #ff6666;
    border-radius: 5px;
    cursor: pointer;
    text-shadow: 0 0 5px #000;
    box-shadow: 0 0 20px rgba(255, 51, 51, 0.5);
    transition: all 0.2s;
    pointer-events: auto;
}

.game-button:hover {
    background: linear-gradient(to bottom, #ff5555, #ff0000);
    box-shadow: 0 0 30px rgba(255, 51, 51, 0.8);
    transform: scale(1.05);
}

.game-button:active {
    transform: scale(0.95);
}

/* Vignette Effect */
#game-container::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle, transparent 40%, rgba(0, 0, 0, 0.8) 100%);
    pointer-events: none;
    z-index: 5;
}