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        <button class="btn window_slide">window slide</button>
        <button class="btn popup">pop up</button>
        <button class="btn slidein">Slide in</button>
        <button class="btn burst">Burse</button>


    *::before {
        padding: inherit;
        margin: inherit;
        box-sizing: inherit;

    html {
        padding: 0;
        margin: 0;
        box-sizing: border-box;

    body {
        --color: #03ffff;
        --hover-b: #000;
        --hover-w: #fff;
        display: grid;
        place-content: center;
        background: linear-gradient(174deg, #233333 0%, #040404 100%, #190101 100%);
        width: 100vw;
        height: 100vh

    .btn {
        background: none;
        border: 2px solid var(--color);
        padding: 2em 4em;
        margin: 1em;
        user-select: none;
        text-transform: uppercase;
        color: var(--color);
        letter-spacing: 2.2px;
        cursor: pointer;
        transform: translateY(0);

        transition: all 0.5s linear;

    /* the inset brings the box-shadow from the inside */
    .window_slide:hover {
        box-shadow: inset 8rem 0 0 0 var(--color), inset -8rem 0 0 0 var(--color);
        color: var(--hover-b);
        transform: translateY(-0.5rem);


    .popup:hover {
        box-shadow: 0rem 0.99rem 0.43rem -0.33rem var(--color);
        transform: translateY(-0.5rem);

    .slidein:hover {
        box-shadow: inset 0 0 0.5rem 4em var(--color);
        transform: translateY(-0.5rem);
        color: var(--hover-b);

    .burst:hover {
        box-shadow: 0 0 1.1rem 1rem var(--color);
        transform: translateY(-0.5rem);

    @media only screen and (max-width: 1080px) {
    div {
        display: grid;
        grid-template-columns: repeat(2, auto);

     @media only screen and (max-width: 600px) {
    div {
        display: grid;
        grid-template-columns: repeat(1, auto);