Gender range slider

Did you just assume my gender!?

by moob

HTML

<div id="wrapper">
    <h1>Did you just assume my gender?</h1>
    <div class="container">
        <label for="gender">Approximate Gender:</label>
        <input id="gender" class="slider" type="range" value="0.5" min="0.00" max="1.00" step="0.01" />
        <ol>
            <li>Female</li>
            <li>Male</li>
        </ol>
    </div>
</div>

CSS

@import url("https://fonts.googleapis.com/css?family=Lato:300");
* {
    -webkit-transition: background 0.7s ease;
    transition: background 0.7s ease;
    box-sizing: border-box;
}

body {
    min-width: 100%;
    min-height: 100%;
    margin: 0;
}

#wrapper {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;
    -webkit-box-pack: center;
    -webkit-justify-content: center;
    -ms-flex-pack: center;
    justify-content: center;
    -webkit-box-align: center;
    -webkit-align-items: center;
    -ms-flex-align: center;
    align-items: center;
    width: 100vw;
    height: 100vh;
    font-family: 'Lato', sans-serif;
    font-weight: 300;
    overflow: hidden;
    background-color: #ccc;
}

#wrapper h1 {
    margin: 20px;
}

#wrapper .container {
    background: #fff;
    min-width: 300px;
    margin:20px;
    border-radius: 16px;
    color: #000;
    font-size: 16px;
    z-index: 1;
    overflow: hidden;
    position: relative;
    box-shadow: 0px 20px 60px -40px #000;
    padding: 30px;
}

#wrapper .container ol {
    list-style: none;
    margin: 0;
    padding: 0;
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;
    -webkit-box-pack: space-between;
    -webkit-justify-content: space-between;
    -ms-flex-pack: space-between;
    justify-content: space-between;
    -webkit-box-align: center;
    -webkit-align-items: center;
    -ms-flex-align: center;
    align-items: center;
}

#wrapper .container ol li {
    list-style: none;
    margin: 0;
    padding: 0;
}

input[type=range].slider {
    -webkit-appearance: none;
    width: 100%;
    margin: 8px 0;
}

input[type=range].slider:focus {
    outline: none;
}

input[type=range].slider::-webkit-slider-runnable-track {
    width: 100%;
    height: 4px;
    cursor: pointer;
    background: #9a9a9a;
    border-radius: 25px;
    border: 0px solid #010101;
}

input[type=range].slider::-webkit-slider-thumb {
    border:...

JavaScript

var wpr = document.querySelector('#wrapper'),
        gEl = document.querySelector('#gender'),
        set = function(val) {
            var bg = "rgb(" + (255 - parseInt(255 * val)) + "," + parseInt(100 * val) + ",255)";
            wpr.style.backgroundColor = bg;
            console.log(val, bg);
        };
    gEl.addEventListener("input", function() {
        set(gEl.value)
    }, false);
    set(gEl.value);