styles.css

body {
    font-family: Arial, sans-serif;
    font-size: 16px;
    background-color: #eee;
    display: grid;
    grid-template-rows: minmax(68px, auto) 1fr;
    grid-template-columns: 100%;
}

h1 {
    text-align: center;
    grid-row: 1;
    grid-column: 1;
    margin-bottom: 20px;
}

form {
    text-align: center;
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    grid-row: 2;
    grid-column: 1;
    max-height: 75px;
}

label {
    display: inline-block;
    width: 90px;
}

input[type="text"] {
    width: 400px;
    padding: 12px 20px;
    margin: 8px 0;
    box-sizing: border-box;
    border: 2px solid #ccc;
    border-radius: 4px;
}

select {
    width: 100px;
    padding: 12px 20px;
    margin: 8px 20px 8px 0;
    box-sizing: border-box;
    border: 2px solid #ccc;
    border-radius: 4px;
    cursor: pointer;
}

button[type="submit"] {
    width: 100px;
    background-color: #4CAF50;
    color: white;
    padding: 14px 20px;
    margin: 8px 0;
    border: none;
    border-radius: 4px;
    cursor: pointer;
}

button[type="submit"]:hover {
    background-color: #45a049;
}

.pre-loader {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: #eee;
    position: absolute;
    top: 0;
    left: 0;
}

.pre-loader .loader {
    width: 50px;
    height: 50px;
    border-radius: 30px;
    border: 5px solid #ccc;
    border-top-color: #333;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    from {
        transform: rotate(0deg);
    }

    to {
        transform: rotate(360deg);
    }
}

#result {
    background-color: white;
    padding: 20px;
    border-radius: 4px;
    grid-row: 3;
    grid-column: 1;
    height: 72vh;
    border: 1px solid #ccc;
}

iframe {
    width: 100%;
    height: 100%;
    border: none;
}