Check out example codes for "css image size adjust". It will help you in understanding the concepts better.

Code Example 1

squareImage {
  border: 1px solid #ddd;	/* thickness and color of border */
  border-radius: 4px;		/* edge rounding of border */
  width: 150px;				/* width of image (px or % or auto) */
  height: auto;				/* height of image (px or % or auto) */
}

Code Example 2

/* Keyword values */
resize: none;
resize: both;
resize: horizontal;
resize: vertical;
resize: block;
resize: inline;

/* Global values */
resize: inherit;
resize: initial;
resize: unset;

Code Example 3

squareImage {
  border: 1px solid #ddd;	/* thickness and color of border */
  border-radius: 4px;		/* edge rounding of border */
  width: 150px;				/* width of image (px or % or auto) */
  height: auto;				/* height of image (px or % or auto) */
}

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