JSFiddle - React, Tailwind, and code Playground

by Ариан Шапиро

HTML

<div class="switch">
    <input type="checkbox">
    <label><i></i></label>
</div>

CSS

*,
*:after,
*:before {
    box-sizing: border-box;
}

.switch input {
    /* First, we make it as wide as the container */
    position: absolute;
    width: 100%;
    height: 100%;
    /* Then, we put it on top of everything else */
    z-index: 100;
    /* Last, we make it invisible */
    opacity: 0;
    /* This one is just for ergonomy */
    cursor: pointer;
}

.switch {
    width: 90px;
    height: 25px;
    margin: 50px auto;
    position: relative;
}

.switch label {
    display: block;
    width: 100%;
    height: 100%;
    position: relative;
    background: #a5a39d;
    border-radius: 40px;
    box-shadow:
        inset 0 2px 4px 1px rgba(0,0,0,0.2),
        0 1px 0 rgba(255,255,255,0.5);
}

.switch label:after {
    content: "";
    position: absolute;
    z-index: -1;
    top: -8px; right: -8px; bottom: -8px; left: -8px;
    border-radius: inherit;
    background: #ccc; /* Fallback */
    background: -webkit-linear-gradient(#f2f2f2, #ababab);
    box-shadow: 0 0 4px rgba(0,0,0,0.3),
        0 1px 1px rgba(0,0,0,0.25);
}

.switch label:before {
    content: "";
    position: absolute;
    z-index: -1;
    top: -12px; right: -12px; bottom: -12px; left: -12px;
    border-radius: inherit;
    background: #eee; /* Fallback */
    background: -webkit-linear-gradient(#e5e7e6, #eee);
    box-shadow: 0 1px 0 rgba(255,255,255,0.5);
    -webkit-filter: blur(1px); /* Smooth trick */
    filter: blur(1px); /* Future-proof */
}

.switch label i {
    display: block;
    height: 100%;
    width: 60%;
    position: absolute;
    right: 40%;
    top: 0;
    z-index: 2;
    border-radius: inherit;
    background: #b2ca9e; /* Fallback */
    background: -webkit-linear-gradient(#f7f2f6, #b2ac9e);
    box-shadow:
        inset 0 1px 0 white,
        0 0 4px rgba(0,0,0,0.3),
        0 5px 5px rgba(0,0,0,0.2);
    -webkit-transition: all 0.3s ease-out;
}

.switch label i:after {
    content: "";
    position: absolute;
    left: 15%;
    top: 25%;
    width: 70%;
   ...

JavaScript

/*
 * In order to make the switch really slide, you have to :
 * add "transition: all 0.3s ease-out" to the .label i
 * change "left: 0;" to "right: 40%" on .label i
 *
 * Problem : you see .label i:before (ON or OFF) moving as well. Could we fix it ? Yes, but only on Firefox, because its the only browser supporting animations and transitions on pseudo-elements.   
 */