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

body,
html {
    height: 100%;
    font-family: Arial, sans-serif;
    font-size: medium;
    background-color: #e0f2f1;
}

a {
    text-decoration: none;
    font-family: Arial, sans-serif;
    color: inherit;
    padding: 30px, 40px;
    color: aqua;
}

/* Container toàn trang, dùng Flex để canh giữa */
.container {
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
}

/* Vùng hình chữ nhật xanh */
.form-box {
    background-color: #2196f3;
    /* màu xanh dương */
    padding: 30px 40px;
    border-radius: 12px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
    color: white;
    text-align: center;
    width: 800px;
}

.form-box h3 {
    margin-bottom: 20px;
}

.form-box p {
    font-size: medium;
    margin-bottom: 20px;
    font-size: 16px;
}

.form-box input[type="text"] {
    width: 100%;
    padding: 10px;
    margin-bottom: 20px;
    border: none;
    border-radius: 6px;
    font-size: 16px;
}

.form-box button {
    padding: 10px 20px;
    font-size: 16px;
    background-color: #0d47a1;
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    width: 100%;
    transition: background-color 0.3s ease;
}

.form-box button:hover {
    background-color: #1565c0;
}