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

Code Example 1

background-image: url("IMAGE_URL"), linear-gradient(#eb01a5, #d13531);

Code Example 2

.gradient {
	background-image: linear-gradient(angle, color1, color2) // angle: 90deg,  color1: red, color2:darkred
}

Code Example 3

.element {
    background: linear-gradient(pink 50%, cyan 50%);
}

Code Example 4

#show_bg_2 {
 
background-image:
  /*two color gradient over an image*/
linear-gradient(to bottom, rgba(245, 246, 252, 0.52), 
rgba(117, 19, 93, 0.73)),url('images/background.jpg');
 
width: 80%;
height: 400px;
background-size: cover;
}

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