/* Mengatur layar dan background dasar */
body {
    margin: 0;
    padding: 0;
    background-color: #2d2d2d;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    overflow: hidden; /* Mencegah scroll di browser */
}

/* Memberi bayangan pada pinggiran game */
#game-container {
    box-shadow: 0 0 20px rgba(0,0,0,0.8);
}

/* --- STYLING UNTUK POP-UP SOAL FISIKA --- */
#ui-container {
    position: absolute;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(0, 0, 0, 0.75); /* Efek gelap transparan */
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 10; /* Memastikan pop-up ada di atas game */
}

/* Class penting untuk menyembunyikan elemen */
.hidden {
    display: none !important;
}

#question-box {
    background: white;
    padding: 30px;
    border-radius: 12px;
    text-align: center;
    max-width: 400px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.5);
}

#question-box input {
    padding: 10px;
    margin: 15px 0;
    width: 80%;
    font-size: 16px;
    border: 2px solid #ccc;
    border-radius: 5px;
}

#question-box button {
    padding: 10px 25px;
    background-color: #2E8B57; /* Hijau hutan */
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 16px;
    font-weight: bold;
}

#question-box button:hover {
    background-color: #1f5f3b;
}

#feedback-text {
    font-weight: bold;
    margin-top: 15px;
}