body {
	font-family: arial, sans-serif;
	color: #202124;
	font-size: 18px;
	line-height: 28px;
	background-color: #D7EEE0;
}

h1 {
	text-align: center;
	font-size: 30px;
	line-height: 40px;
	color: #333;
}

h2 {
	color: #666666;
	line-height: 30px;
	font-size: 20px;
}


h3 {
	color: #333333;
	line-height: 25px;
	font-size: 15px;
	font-style: italic;
	font-weight: normal;
}

#sutun {
	margin: 0 auto;
	width: 80%;
	max-width: 800px;
	background-color: #EAFFEC;
}
#cerceve{
	margin: 0 auto;
	width: 80%;
	max-width: 800px;
	background-color: #FFF;
	border-top-style: double;
	border-right-style: double;
	border-bottom-style: double;
	border-left-style: double;
}

<style>  
.youtube-preview {
  position: relative;
  width: 100%;
  max-width: 330px;
  aspect-ratio: 16 / 9;
  cursor: pointer;
  background-color: #000;
  margin: 20px auto;
	color: #FFF;
}
.youtube-preview img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}


/* PLAY BUTONU */
.youtube-preview::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 80px; /* buton boyutu */
  height: 56px;
  transform: translate(-50%, -50%);
  background-image: url('images/youtube2.png'); /* şeffaf butonun yolu */
  background-size: contain;
  background-repeat: no-repeat;
  background-position: center;
  pointer-events: none;
}