body {
    margin: 0;
    padding: 0;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: #ffe6e6; /* Màu nền hồng nhạt dễ thương */
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    overflow: hidden; /* Ẩn thanh cuộn khi có hiệu ứng bay */
}

.container {
    text-align: center;
    background: white;
    padding: 40px 50px;
    border-radius: 20px;
    box-shadow: 0 10px 30px rgba(255, 102, 102, 0.2);
    position: relative;
    z-index: 10;
}

h1 {
    color: #ff4d4d;
    margin-bottom: 10px;
}

p {
    color: #666;
    font-size: 18px;
    margin-bottom: 20px;
}

button {
    background-color: #ff6666;
    color: white;
    border: none;
    padding: 15px 30px;
    font-size: 18px;
    font-weight: bold;
    border-radius: 50px;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(255, 102, 102, 0.4);
}

button:hover {
    background-color: #ff3333;
    transform: scale(1.05) translateY(-3px);
}

.hidden {
    display: none;
}

#message-box h2 {
    color: #ff3385;
    margin-top: 30px;
    animation: fadeIn 1s ease-in-out;
}

/* Hiệu ứng chữ xuất hiện */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(-20px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Hiệu ứng icon bay lên */
.floating-icon {
    position: absolute;
    font-size: 28px;
    bottom: -50px;
    animation: floatUp linear forwards;
    z-index: 1;
}

@keyframes floatUp {
    0% { transform: translateY(0) rotate(0deg); opacity: 1; }
    100% { transform: translateY(-110vh) rotate(360deg); opacity: 0; }
}