examen.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
    <style>
input[type=number]::-webkit-inner-spin-button, 
input[type=number]::-webkit-outer-spin-button { 
  -webkit-appearance: none; 
  margin: 0; 
}input[type=number] { -moz-appearance:textfield; }
*{
    text-align: center;
}
</style>
<body>
    <form method="post" action="examen.php">
        <h1>SELECCIONE EL SABOR DEL PANQUE</h1>
        <h6>*EL PRECIO VARIA SEGUN EL SABOR*</h6>
        <select name="sabores" id="sabores">
            <option value="15">Nuez</option>       
            <option value="12">Pasas</option>  
            <option value="18">Arandano</option>   
            <option value="15">Almendra</option>   
        </select>
        <br><br>
        <h2>INGRESE LA CANTIDAD DE PANQUES</h2>
        <br><br>
        <input type="number" name="cantidad" id="canti" placeholder="Cantidad" step="30" required="yes" > 
        <br><br>
        <input type="submit" value="CALCULAR INGREDIENTES">
    </form>
</body>
</html>