body, html {
    margin: 0;
    padding: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
    background-color: #050510;
    font-family: 'Courier New', Courier, monospace;
    color: white;
}

#game-container {
    width: 100vw;
    height: 100vh;
    position: relative;
    background-image: 
        radial-gradient(white, rgba(255,255,255,.2) 2px, transparent 40px),
        radial-gradient(white, rgba(255,255,255,.15) 1px, transparent 30px),
        radial-gradient(white, rgba(255,255,255,.1) 2px, transparent 40px);
    background-size: 550px 550px, 350px 350px, 250px 250px;
    background-position: 0 0, 40px 60px, 130px 270px;
}

#ui-layer {
    position: absolute;
    top: 20px;
    left: 20px;
    z-index: 100;
}

#score-board {
    font-size: 24px;
    text-shadow: 0 0 10px #00f2ff;
}

#ship {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    font-size: 50px;
    transition: left 0.1s ease-out;
    user-select: none;
}

.alien {
    position: absolute;
    font-size: 30px;
    transition: all 0.2s linear;
}

.bullet {
    position: absolute;
    width: 4px;
    height: 15px;
    background: #00f2ff;
    box-shadow: 0 0 8px #00f2ff;
    border-radius: 2px;
}

.alien-bullet {
    background: #ff0055;
    box-shadow: 0 0 8px #ff0055;
}

.explosion {
    animation: explode 0.5s ease-out forwards;
    pointer-events: none;
}

@keyframes explode {
    0% { transform: scale(0.5); opacity: 1; }
    100% { transform: scale(2); opacity: 0; }
}

#game-over {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.85);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

.hidden {
    display: none !important;
}

.modal {
    background: #1a1a2e;
    padding: 50px;
    border-radius: 20px;
    text-align: center;
    border: 2px solid #00f2ff;
    box-shadow: 0 0 30px rgba(0, 242, 255, 0.3);
}

.modal h1 {
    margin-top: 0;
    color: #00f2ff;
    font-size: 48px;
    text-transform: uppercase;
}

.modal p {
    font-size: 24px;
    margin: 20px 0;
}

#restart-btn {
    background: transparent;
    color: #00f2ff;
    border: 2px solid #00f2ff;
    padding: 15px 30px;
    font-size: 20px;
    border-radius: 5px;
    cursor: pointer;
    text-transform: uppercase;
    transition: all 0.3s;
}

#restart-btn:hover {
    background: #00f2ff;
    color: #1a1a2e;
    box-shadow: 0 0 20px #00f2ff;
}