* {
    box-sizing: border-box;
}

body {
    font-family: Arial, sans-serif;
    background-color: #f2f4f7;
    margin: 0;
    padding: 20px;
}

main {
    max-width: 650px;
    margin: 0 auto;
    background-color: white;
    padding: 25px;
    border-radius: 10px;
}

header {
    text-align: center;
    margin-bottom: 20px;
}

fieldset {
    border: 1px solid #cccccc;
    padding: 20px;
    border-radius: 8px;
}

legend {
    font-weight: bold;
    padding: 0 8px;
}

label {
    display: block;
    margin-top: 15px;
    margin-bottom: 6px;
    font-weight: bold;
}

input {
    width: 100%;
    padding: 10px;
    font-size: 16px;
}

.studentNumber {
    display: flex;
    align-items: center;
    gap: 8px;
    flex-wrap: wrap;
}

.studentNumber p:first-child {
    font-weight: bold;
    margin: 0;
}

.studentNumber input {
    width: 45px;
    text-align: center;
}

#student_error {
    width: 100%;
}

.mobileNumber {
    display: flex;
    align-items: center;
    gap: 10px;
}

.mobileNumber input {
    width: auto;
}

.mobileNumber input:first-child {
    width: 70px;
    text-align: center;
    background-color: #eeeeee;
}

.mobileNumber input:last-child {
    flex: 1;
}

section input[type="checkbox"] {
    width: auto;
    margin-top: 15px;
}

section label {
    display: inline;
    font-weight: normal;
}

button {
    width: 100%;
    margin-top: 20px;
    padding: 12px;
    font-size: 18px;
    background-color: #0057b8;
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
}

button:hover {
    background-color: #003f87;
}

[id$="_error"] {
    color: red;
    font-size: 14px;
    margin-top: 5px;
}