how to add a gradient color in css code example

Example 1: linear gradient css

/* A gradient tilted 100 degrees,
   starting gray and finishing black */

.class {
    background: linear-gradient(100deg, rgba(63, 63, 63, 0.8) 0%, rgba(255, 255, 255, 0) 25%);
}

/* A gradient going from the bottom to top
   starting red and finishing orange */

.class {
    background: linear-gradient(to top, #f32b60, #ff8f1f);
}

Example 2: gradient css background

/*From bottom to top*/
background: rgb(166,166,166);
background: linear-gradient(0deg, rgba(166,166,166,1) 0%, rgba(255,255,255,1) 29%);