html, body {
    height: 100%;
    margin: 0;
    padding: 0;
    background: #0f1020;
    color: #ffffff;
    font-family: system-ui, -apple-system, Segoe UI, Roboto, Ubuntu, Cantarell, Noto Sans, Helvetica, Arial, "Apple Color Emoji", "Segoe UI Emoji";
    user-select: none;
}

#game {
    display: block;
    width: 100vw;
    height: 100vh;
    outline: none;
    image-rendering: pixelated;
    background: linear-gradient(180deg, #0f1020 0%, #0c0d18 65%, #090a12 100%);
    user-select: none;
}

.hud {
    position: fixed;
    top: env(safe-area-inset-top);
    left: 0;
    right: 0;
    display: flex;
    justify-content: space-between;
    padding: 16px;
    pointer-events: none;
    user-select: none;
    text-shadow: 0 2px 8px rgba(0,0,0,.45);
    font-weight: 600;
    letter-spacing: 0.5px;
    user-select: none;
}

.btn {
    position: fixed;
    right: 16px;
    bottom: calc(16px + env(safe-area-inset-bottom));
    padding: 12px 16px;
    background: rgba(255,255,255,0.08);
    border: 1px solid rgba(255,255,255,0.12);
    border-radius: 16px;
    backdrop-filter: blur(6px);
    -webkit-backdrop-filter: blur(6px);
    font-weight: 600;
    cursor: pointer;
    transition: transform .08s ease-out;
    z-index: 10;
    user-select: none;
}

.btn:active { transform: scale(0.98); }

.btn2 {
    color: #000000;
    background: rgba(255,255,255,0.08);
    user-select: none;
}

#menu {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    display: flex;
    flex-direction: column;
    gap: 12px;
    text-align: center;
    z-index: 20;
    user-select: none;
}

#menu button {
    padding: 12px 24px;
    border-radius: 12px;
    border: none;
    font-weight: bold;
    background: #39d0ff;
    color: #0b2233;
    cursor: pointer;
    transition: transform .1s;
    user-select: none;
}

#menu button:active { transform: scale(0.96); }