* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Microsoft YaHei', sans-serif;
    line-height: 1.6;
    background: transparent;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
}

.main-container {
    max-width: 300px;
    width: 80%;
    margin: 0 auto;
    padding: 2.5rem;
    background: rgba(25, 25, 35, 0.2);
    backdrop-filter: blur(8px);
    border-radius: 20px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.age {
    font-size: 24px;
    margin-bottom: 20px;
    color: white;
}

.btn {
    padding: 10px 20px;
    font-size: 16px;
    background-color: #4CAF50;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
}

.btn:hover {
    background-color: #45a049;
}

@media screen and (max-width: 768px) {
    .main-container {
        width: 90%;
        padding: 1.5rem;
    }
}

@media screen and (max-width: 576px) {
    .main-container {
        width: 95%;
        padding: 1rem;
    }
}