Check out example codes for "make buttons round css". It will help you in understanding the concepts better.

Code Example 1

.btn {
  display:block;
  height: 300px;
  width: 300px;
  border-radius: 50%;
  border: 1px solid red;
  
}

Code Example 2

.button {
  background-color: #4CAF50;
  border: none;
  color: white;

    
  padding: 20px;
  text-align: center;
  
  text-decoration: none;
  display: inline-block;
  font-size: 16px;

    margin: 4px 2px;
}

.button1 {border-radius: 2px;}
.button2 
  {border-radius: 4px;}
.button3 {border-radius: 8px;}
.button4 
  {border-radius: 12px;}
.button5 {border-radius: 50%;}

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