style.css

/* fill wallpaper, put content in the middle */
body {
    background: url(background.jpg) fixed center;
    background-size: cover;
    display: flex;
    justify-content: center;
}

/* background, soft corners, padding and margin for the grid container */
.grid-container {
    display: flex;
    background-color: rgba(0, 0, 0, 0.516);
    margin: 100px;
    padding: 20px;
    border-radius: 5%;
}

/* padding for the grid */
.grid-item {
    padding: 10px;
}

/* white color for the texts */
label{
    color: rgba(255, 255, 255, 0.516);
    opacity: 1;
}

h2{
    color: rgba(255, 255, 255, 0.516);
}

/* border and padding for the saved results part */
#saved_result{
    border:1px solid black;
    padding: 9px;
}

/* a decent width for textbox */
textbox{
    width: 150px;
}