Check out example codes for "uigradients". It will help you in understanding the concepts better.

Code Example 1

background: #000428; /* fallback for old browsers */
  background: -webkit-linear-gradient(to bottom, #000428, #004e92); /* Chrome 10-25, Safari 5.1-6 */
  background: linear-gradient(to bottom, #000428, #004e92); /* W3C, IE 10+/ Edge, Firefox 16+, Chrome 26+, Opera 12+, Safari 7+ */

Code Example 2

background: #0f2027; /* fallback for old browsers */
  background: -webkit-linear-gradient(to right, #0f2027, #203a43, #2c5364); /* Chrome 10-25, Safari 5.1-6 */
  background: linear-gradient(to right, #0f2027, #203a43, #2c5364); /* W3C, IE 10+/ Edge, Firefox 16+, Chrome 26+, Opera 12+, Safari 7+ */

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