css size

CSS
#myID {
  height: 100px; /* Sets the height */
  width: 200px; /* Sets the width */
}
/* or... */
.myClass {
  height: 220px; /* Sets the height */
  width: 40px; /* Sets the width */
}
/* They both work! */div {
  height: 
200px;
  width: 50%;
  background-color: powderblue;
} 
Source

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