Background-color opacity CSS code example

Example 1: background color semi transparent

.transparent {
    background-color: rgba(255, 255, 255, 0.5);
}
.transparent {
    opacity: 0.5;
}

Example 2: css opacity background color

background: rgba(255, 255, 255, 0.25);

Example 3: background color cs rgba

#p1 {background-color:rgba(255,0,0,0.3);}

Example 4: background color with opacity

h1 {background-color:rgba(255,0,0,0.3);}

Example 5: background opacity css hex

background-color: #ff000088; <--- the 88 is the alpha
background-color: #ff0000 50%;

Example 6: css set background opacity

/*background color opacity with explainations */
rgba(51, 170, 51, .1)    /*  10% opaque green */ 
rgba(51, 170, 51, .4)    /*  40% opaque green */ 
rgba(51, 170, 51, .7)    /*  70% opaque green */ 
rgba(51, 170, 51,  1)    /* full opaque green */