body {
    margin: 0;
    background: #000;
    font-family: sans-serif;
    overflow: hidden;
    color: white;
}

.canvas-container {
    width: 100vw;
    height: 100vh;
}

.ui {
    position: absolute;
    top: 20px;
    left: 20px;
    pointer-events: none;
    z-index: 10;
}

h1 {
    margin: 0;
    font-size: 1.2rem;
    color: #ffeb3b;
}

p {
    margin: 5px 0 0;
    font-size: 0.85rem;
    color: #aaa;
}

.controls {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 10px;
    z-index: 10;
}

.btn {
    padding: 12px 25px;
    background: #ffeb3b;
    color: black;
    border: none;
    border-radius: 30px;
    font-weight: bold;
    cursor: pointer;
    font-size: 1rem;
    box-shadow: 0 4px 10px rgba(0,0,0,0.5);
}
.btn:active {
    transform: scale(0.95);
}

/* ★視点ボタン専用の色（青系） */
.view-btn {
    background: #03a9f4;
    color: white;
}

.back-btn {
    position: absolute;
    top: 20px;
    right: 20px;
    z-index: 10;
    text-decoration: none;
    color: #333;
    font-weight: bold;
    background: white;
    padding: 8px 16px;
    border-radius: 20px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.3);
}