body, html {
    margin: 0;
    padding: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
    background-color: #121212;
    font-family: 'Orbitron', sans-serif;
    color: white;
}

.top-nav {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(10px);
    display: flex;
    justify-content: center;
    padding: 10px 0;
    z-index: 1000;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.top-nav a {
    color: #888;
    text-decoration: none;
    margin: 0 15px;
    font-size: 0.8rem;
    font-weight: 700;
    transition: all 0.3s ease;
    text-transform: uppercase;
}

.top-nav a:hover, .top-nav a.active {
    color: #ff3e3e;
    text-shadow: 0 0 10px rgba(255, 62, 62, 0.5);
}

#gameCanvas {
    display: block;
    width: 100vw;
    height: 100vh;
}

#game-ui {
    position: absolute;
    top: 70px;
    left: 20px;
    right: 20px;
    pointer-events: none;
    display: flex;
    flex-direction: column;
}

#top-bar {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    width: 100%;
}

#score-container, #level-container {
    background: rgba(0, 0, 0, 0.7);
    padding: 10px 20px;
    border-radius: 10px;
    border-left: 4px solid #ff3e3e;
    pointer-events: auto;
}

#level-select {
    background: transparent;
    border: none;
    color: white;
    font-family: 'Orbitron', sans-serif;
    font-size: 1.5rem;
    font-weight: 700;
    cursor: pointer;
    outline: none;
}

#level-select option {
    background: #121212;
}

.label {
    display: block;
    font-size: 0.7rem;
    color: #ff3e3e;
    margin-bottom: 2px;
}

#score {
    font-size: 2rem;
    font-weight: 700;
}

#message {
    margin-top: 10px;
    font-size: 0.9rem;
    opacity: 0.7;
    animation: pulse 1.5s infinite;
}

@keyframes pulse {
    0% { opacity: 0.4; }
    50% { opacity: 1; }
    100% { opacity: 0.4; }
}

#game-over {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: rgba(0, 0, 0, 0.9);
    padding: 40px;
    border-radius: 20px;
    text-align: center;
    border: 2px solid #ff3e3e;
    box-shadow: 0 0 30px rgba(255, 62, 62, 0.3);
    z-index: 2000;
}

#game-over h1 {
    font-size: 3rem;
    margin: 0;
    color: #ff3e3e;
    text-shadow: 0 0 20px rgba(255, 62, 62, 0.5);
}

#game-over p {
    font-size: 1.2rem;
    margin: 20px 0;
}

#restart-btn {
    background: #ff3e3e;
    color: white;
    border: none;
    padding: 15px 40px;
    font-family: 'Orbitron', sans-serif;
    font-weight: 700;
    border-radius: 50px;
    cursor: pointer;
    transition: all 0.3s ease;
}

#restart-btn:hover {
    background: #ff1a1a;
    transform: scale(1.05);
    box-shadow: 0 0 20px rgba(255, 62, 62, 0.4);
}

.hidden {
    display: none !important;
}