body {
    margin: 0;
    padding: 0;
    background-color: #0b0b0d;
    color: #fff;
    font-family: 'Arial Black', Gadget, sans-serif;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100vh;
    overflow: hidden;
}

#ui-container {
    position: absolute;
    z-index: 10;
}

#menu {
    background: rgba(20, 20, 25, 0.95);
    padding: 50px;
    border: 4px solid #3e4444;
    border-radius: 20px;
    text-align: center;
    box-shadow: 0 0 50px rgba(255, 0, 0, 0.2);
}

h1 {
    font-size: 48px;
    color: #f1c40f;
    text-shadow: 3px 3px #c0392b;
    margin-bottom: 30px;
}

button {
    background: #e74c3c;
    color: white;
    border: none;
    padding: 15px 40px;
    font-size: 20px;
    font-weight: bold;
    cursor: pointer;
    margin: 10px;
    border-bottom: 5px solid #c0392b;
    transition: 0.1s;
}

button:hover {
    background: #ff5e4d;
    transform: translateY(-2px);
}

button:active {
    transform: translateY(4px);
    border-bottom-width: 0;
}

input {
    padding: 15px;
    font-size: 24px;
    border-radius: 8px;
    border: none;
    width: 150px;
    text-align: center;
}

.hidden {
    display: none;
}

#gameCanvas {
    display: none;
    background: #1e272e;
    border: 5px solid #fff;
    box-shadow: 0 0 100px rgba(0,0,0,0.8);
}

.btn-back { background: #7f8c8d; border-bottom-color: #2c3e50; }
.btn-start { background: #27ae60; border-bottom-color: #219150; }