🏟

 <div id="reklam-kapsayici" style="width:728px; height:90px; position:relative; overflow:hidden;">

  <div id="reklam1" style="width:100%; height:100%; display:flex; align-items:center; justify-content:center; font-size:24px; font-weight:bold; position:absolute; top:0; left:0; opacity:1; transition:opacity 1s;">

    REKLAM BURAYA

  </div>

  <div id="reklam2" style="width:100%; height:100%; display:flex; align-items:center; justify-content:center; font-size:24px; font-weight:bold; position:absolute; top:0; left:0; opacity:0; transition:opacity 1s;">

    REKLAM BURAYA

  </div>

</div>

<script>

  let aktif = 1;

  setInterval(() => {

    const r1 = document.getElementById("reklam1");

    const r2 = document.getElementById("reklam2");

    if (aktif === 1) {

      r1.style.opacity = 0;

      r2.style.opacity = 1;

      aktif = 2;

    } else {

      r2.style.opacity = 0;

      r1.style.opacity = 1;

      aktif = 1;

    }

  }, 30000); // 30 saniyede bir geçiş

</script>  (code-box)