<style>

.gallery {display: grid;grid-template-columns: repeat(4, 1fr);gap: 10px;}

.gallery-item {background-color: #ddd;padding: 20px;text-align: center;}

</style>

<div class="gallery">

    <div class="gallery-item">1</div>

    <div class="gallery-item">2</div>

    <div class="gallery-item">3</div>

    <div class="gallery-item">4</div>

    <div class="gallery-item">5</div>

    <div class="gallery-item">6</div>

    <div class="gallery-item">7</div>

    <div class="gallery-item">8</div>

    <div class="gallery-item">9</div>

    <div class="gallery-item">10</div>

    <div class="gallery-item">11</div>

    <div class="gallery-item">12</div>

    <div class="gallery-item">13</div>

    <div class="gallery-item">14</div>

    <div class="gallery-item">15</div>

    <div class="gallery-item">16</div>

</div>