<link href="https://fonts.googleapis.com/css?family=Bree+Serif&display=swap" rel="stylesheet">
<style type="text/css">
    h1, p{
        font-family: 'Bree Serif', serif;
        text-align: center;
    }
    table{
        border: 5px outset darkblue;
        background: linear-gradient(to right, #0033cc 0%, #ff0066 100%);
    }
    th{
        font-family: 'Bree Serif', serif;
        font-size: 25px;
        width: 200px;
    }
    td{
        font-family: 'Bree Serif', serif;
        font-size: 20px;
    }
    td.batas{
        height: 5px;
        border-radius: 50px;
        background-color: cyan;
    }
    .no{
        width: 50px;
    }
    input{
        border: 2px inset black;
        background-color: silver;
        font-family: 'Bree Serif', serif;
        font-size: 15px;
        border-radius: 50px;
        text-align: center;
        width: 200px;
    }
    input#button{
        border: 3px outset blue;
        background-color: silver;
        font-family: 'Bree Serif', serif;
        transition-duration: 0.5s;
        font-size: 15px;
        border-radius: 50px;
        width: 50px;
    }
    input#button:hover{
        border: 3px outset blue;
        background: linear-gradient(to bottom, #0033cc 0%, #ff0066 100%);
        font-family: 'Bree Serif', serif;
        font-size: 17px;
        border-radius: 50px;
        width: 50px;
        color: white;
    }
</style>

<h1>Form Input Data Siswa</h1>
<form id="studi1" name="studi1" method="post">
    <p>
        Masukan Jumlah Siswa :
        <input type="number" name="jumlahSiswa" id="jumlahSiswa" autocomplete="off" required="">
        <input type="submit" name="button" id="button" value="OK">
    </p>
</form>
<table align="center" cellspacing="5">
    <tr>
        <th class="no">No</th>
        <th>NIS</th>
        <th>Nama</th>
        <th>Alamat</th>
    </tr>
    <tr>
        <td class="batas" colspan="4"></td>
    </tr>

    <?php
    if (isset($_POST['button'])) {
        $jumlahSiswa = $_POST['jumlahSiswa'];

        for ($x = 1; $x <= $jumlahSiswa; $x++) {
    ?>
    <tr>
        <td>
            <input class="no" type="text" name="no" id="no" autocomplete="off" value="<?php echo $x; ?>" disabled>
        </td>
        <td>
            <input type="text" name="nis" id="nis" autocomplete="off">
        </td>
        <td>
            <input type="text" name="nama" id="nama" autocomplete="off">
        </td>
        <td>
            <input type="text" name="alamat" id="alamat" autocomplete="off">
        </td>
    <?php } } ?>
    </tr>
</table>