Scroll

Created for humanreviews.me

by levchenko_d

HTML

<div id="wrapper" class="__scroll_wrap __wrapper">
    <div class="__content">Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat..</div>
    <div class="__master"> <i class="__imit"></i>

    </div>
    <div class="__scroll"></div>
</div>
<div id="as">
    <img src="http://images3.wikia.nocookie.net/__cb20110112073950/simpsons/images/6/69/The_simpsons_ralph_wiggum-1-.png" />I'm Appended!
    <br/>
    <br/>Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.</div>

CSS

/* Use me */
 .__scroll_wrap, .__containter {
    width: 200px;
    height: 300px;
}
.__scroll_wrap {
    position: relative;
    display: inline-block;
    margin: 20px;
    border: solid 1px silver;
    overflow: hidden;
    border-radius: 5px;
}
.__containter {
    width: 220px;
}
.__content {
    width: 100%;
    padding: 0 40px 0 0;
    height: 300px;
    overflow: auto;
}
.__scroll {
    position: absolute;
    width: 9px;
    min-height: 25px;
    background: black;
    top: 0px;
    right: 3px;
    z-index: 99;
    border-radius: 5px;
    opacity: 0;
    -webkit-transition: opacity 0.15s;
}
.__scroll_wrap:hover .__scroll {
    opacity: 0.1;
}
.__master {
    width: 19px;
    height: 300px;
    position: absolute;
    top: -15px;
    right: 0px;
    padding: 30px 0;
    background: black;
    overflow-y: auto;
    z-index: 999;
    opacity:0;
    cursor: pointer;
}
.__master:hover ~ .__scroll {
    opacity: 0.3;
}
.__master:active ~ .__scroll {
    opacity: 0.5;
}
.__master i {
    display: block;
    height: 703px;
}
/*Don't use me*/
 #as {
    display: inline-block;
}
img {
    width: 100%;
}
body {
    font-family: calibri;
}

.__scrolled{
    box-shadow: inset 0 0 10px black;    
}

JavaScript

var Scroll = (function () {
    /*
    function calculate(item){
         var h = wrap[i].clientHeight
         var ch = content[i].scrollHeight;
         d = h / ch;
         if (ch > h) {
           scroll[i].style.height = (d * h) + 'px';
           scroll[i].style.display = 'block';
           imit[i].style.height = ch + 'px';
         } else {
           scroll[i].style.display = 'none';
         }
    };
    */
    function init(callback) {
        var Class = function (className) {
                return document.getElementsByClassName(className);
            },
    
            ClassIn = function (item, className) {
                return item.getElementsByClassName(className);
            },
            
            setClass = function(item){
                
                item.className = item.className.replace(' __scrolled','');
                
                if(item.scrollTop > 50){
                    item.className = item.className + ' __scrolled'; 
                }
            }
            
            master = Class('__master'),
            wrap = Class('__scroll_wrap'),
            content = Class('__content'),
            scroll = Class('__scroll'),
            imit = Class('__imit'),
            l = imit.length,

            contentHeight = 0;

        for (var i = 0; i < l; i++) {
            var h = wrap[i].clientHeight
            var ch = content[i].scrollHeight;
            d = h / ch;
            if (ch > h) {
                scroll[i].style.height = (d * h) + 'px';
                scroll[i].style.display = 'block';
                imit[i].style.height = ch + 'px';
            } else {
                scroll[i].style.display = 'none';
            }
        }

        for (var i = 0; i < l; i++) {
            master[i].onscroll = function () {
                setClass(ClassIn(this.parentNode, '__content')[0]);
                ClassIn(this.parentNode, '__content')[0].scrollTop = this.scrollTop;
            }
        }

        for...