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

Code Example 1

.image { position: relative; }
.image img { display: block; position: relative; z-index: 1; width: 100%; }
.image .fade { position: absolute; bottom: 0; width: 100%; height: 150px; z-index: 2; background: rgba(255, 255, 255, 0) linear-gradient(to bottom, rgba(255, 255, 255, 0) 0%, rgba(255, 255, 255, 0.8) 80%) repeat scroll 0 0;  }

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