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<div class="container">
    <div class="box a">A
        <br>class
        <br>box</div>
    <div class="box b">B
        <br>class
        <br>box</div>
    <div class="box a">A
        <br>class
        <br>box</div>
    <div class="box c">C
        <br>class
        <br>box</div>
    <div class="box a">A
        <br>class
        <br>box</div>
</div>
<div class="controls">Class to apply styling:
    <select id="classSelect">
        <option value=".box">Box (all)</option>
        <option value=".a">A</option>
        <option value=".b">B</option>
        <option value=".c">C</option>
    </select>
    <button class="resetall" onclick="clearAll()">Reset All</button>
    <br>Set Float:
    <select onChange="changeStyle(this, 'float')">
        <option default value="">Reset</option>
        <option value="right">Right</option>
        <option value="left">Left</option>
        <option value="none">None</option>
    </select>
    <br>Set Clear:
    <select onChange="changeStyle(this, 'clear')">
        <option default value="">Reset</option>
        <option value="right">Right</option>
        <option value="left">Left</option>
        <option value="none">None</option>
        <option value="both">Both</option>
    </select>
    <br>Set Display:
    <select onChange="changeStyle(this, 'display')">
        <option default value="">Reset</option>
        <option value="none">None</option>
        <option value="block">Block</option>
        <option value="inline">Inline</option>
        <option value="inline-block">Inline-block</option>
        <option value="table">Table</option>
    </select>
    <br>Set Vertical-align:
    <select onChange="changeStyle(this, 'verticalAlign')">
        <option default value="">Reset</option>
        <option value="top">Top</option>
        <option value="middle">Middle</option>
        <option value="bottom">Bottom</option>
    </select>
    <br>Set Transition:
    <select onChange="changeStyle(this, 'transition')">
        <option default value="">Reset</option>
        <option value="all .5s">0.5 sec</option>
        <option value="all 1s">1 sec</option>
        <option value="all 3s">3 sec</option>
    </select>
    <br>Set Visibility:
    <select onChange="changeStyle(this, 'visibility')">
        <option default value="">Reset</option>
        <option value="hidden">Hidden</option>
        <option value="visible">Visible</option>
    </select>
    <br>
    <hr>Set Position:
    <select onChange="changeStyle(this, 'position')">
        <option default value="">Reset</option>
        <option value="fixed">Fixed</option>
        <option value="relative">Relative</option>
        <option value="absolute">Absolute</option>
    </select>
    <br>Set Top:
    <input type="range" value="0" min="-100" max="400" onChange="changeStyle(this, 'top', 'px')" />
    <button onclick="{changeStyle(this, 'top'); this.previousSibling.value=0;}">Reset</button>
    <br>Set Left:
    <input type="range" value="0" min="-100" max="400" onChange="changeStyle(this, 'left', 'px')" />
    <button onclick="{changeStyle(this, 'left'); this.previousSibling.value=0;}">Reset</button>
    <br>
    <hr>Set Size:
    <input type="range" value="80" min="10" max="160" onChange="{changeStyle(this, 'height', 'px');changeStyle(this, 'width', 'px')}" />
    <button onclick="{changeStyle(this, 'height');changeStyle(this, 'width'); this.previousSibling.value=80;}">Reset</button>
    <br>Set Height:
    <input type="range" value="80" min="10" max="160" onChange="changeStyle(this, 'height', 'px')" />
    <button onclick="{changeStyle(this, 'height'); this.previousSibling.value=80;}">Reset</button>
    <br>Set Width:
    <input type="range" value="80" min="10" max="160" onChange="changeStyle(this, 'width', 'px')" />
    <button onclick="{changeStyle(this, 'width'); this.previousSibling.value=80;}">Reset</button>
    <br>Set Padding:
    <input type="range" value="0" min="0" max="20" onChange="changeStyle(this, 'padding', 'px')" />
    <button onclick="{changeStyle(this, 'padding'); this.previousSibling.value=0;}">Reset</button>
    <br>Set Margin:
    <input type="range" value="0" min="0" max="40" onChange="changeStyle(this, 'margin', 'px')" />
    <button onclick="{changeStyle(this, 'margin'); this.previousSibling.value=0;}">Reset</button>
    <br>    <hr>
    Set Background Color:
    <select onChange="changeStyle(this, 'backgroundColor')">
        <option default value="">Reset</option>
        <option value="purple">Purple</option>
        <option value="yellow">Yellow</option>
        <option value="cyan">Cyan</option>
        <option value="fuchsia">Fuchsia</option>
        <option value="antiquewhite">Antique White</option>
        <option value="black">Black</option>
    </select> 
    <br>Set Opacity:
<input type="range" value="1" min="0" max="1" step=".05" onChange="changeStyle(this, 'opacity')" />
    <button onclick="{changeStyle(this, 'opacity'); this.previousSibling.value=1;}">Reset</button>
    <br>Set Text Color:
    <select onChange="changeStyle(this, 'color')">
        <option default value="">Reset</option>
        <option value="purple">Purple</option>
        <option value="yellow">Yellow</option>
        <option value="cyan">Cyan</option>
        <option value="fuchsia">Fuchsia</option>
        <option value="antiquewhite">Antique White</option>
        <option value="black">Black</option>
    </select> 
    <br>Set Font Family:
    <select onChange="changeStyle(this, 'fontFamily')">
        <option default value="">Reset</option>
        <option value="sans-serif">Sans-serif</option>
        <option value="serif">Serif</option>
        <option value="monospace">Monospace</option>
        <option value="impact">Impact</option>
        <option value="cursive">Cursive</option>
    </select>
    <br>Set Font Size:
<input type="range" value="0" min="7" max="40" onChange="changeStyle(this, 'fontSize', 'px')" />
    <button onclick="{changeStyle(this, 'fontSize'); this.previousSibling.value=0;}">Reset</button>
    <br>Set Border Color:
    <select onChange="changeStyle(this, 'borderColor')">
        <option default value="">Reset</option>
        <option value="purple">Purple</option>
        <option value="yellow">Yellow</option>
        <option value="cyan">Cyan</option>
        <option value="fuchsia">Fuchsia</option>
        <option value="antiquewhite">Antique White</option>
        <option value="black">Black</option>
    </select> 
    <br>Set Border Style:
    <select onChange="changeStyle(this, 'borderStyle')">
        <option default value="">Reset</option>
        <option value="dotted">Dotted</option>
        <option value="dashed">Dashed</option>
        <option value="solid">Solid</option>
    </select>
    <br>Set Border Width:
<input type="range" value="0" min="0" max="10" onChange="changeStyle(this, 'borderWidth', 'px')" />
    <button onclick="{changeStyle(this, 'borderWidth'); this.previousSibling.value=0;}">Reset</button>
     <br>Set Border Radius:
<input type="range" value="0" min="0" max="60" onChange="changeStyle(this, 'borderRadius', 'px')" />
    <button onclick="{changeStyle(this, 'borderRadius'); this.previousSibling.value=0;}">Reset</button>
<hr>Text Shadow: 
    <br>Set Shadow Xoffset:
<input id="tsx" type="range" value="0" min="0" max="15" onChange="changeBoxShadow('','text')" />
<br>Set Shadow Yoffset:
<input id="tsy" type="range" value="0" min="0" max="15" onChange="changeBoxShadow('','text')" />
<br>Set Shadow Blur Size:
<input id="tblur" type="range" value="0" min="0" max="15" onChange="changeBoxShadow('','text')" />
    <br>Set Shadow Color:
    <select id="tcolor" onChange="changeBoxShadow('','text')">
        <option default value="">Reset</option>
        <option value="purple">Purple</option>
        <option value="yellow">Yellow</option>
        <option value="cyan">Cyan</option>
        <option value="fuchsia">Fuchsia</option>
        <option value="antiquewhite">Antique White</option>
        <option value="black">Black</option>
    </select><br>
    <button onclick="{document.getElementById('tsx').value=0; document.getElementById('tsy').value=0; document.getElementById('tblur').value=0;
document.getElementById('tcolor').options[0].selected='selected';
changeBoxShadow('clear','text');}">Reset</button>
         
         <hr>Box Shadow: 
    <br>Set Shadow Xoffset:
<input id="bsx" type="range" value="0" min="0" max="15" onChange="changeBoxShadow()" />
<br>Set Shadow Yoffset:
<input id="bsy" type="range" value="0" min="0" max="15" onChange="changeBoxShadow()" />
<br>Set Shadow Blur Size:
<input id="bsblur" type="range" value="0" min="0" max="15" onChange="changeBoxShadow()" />
    <br>Set Shadow Color:
    <select id="bscolor" onChange="changeBoxShadow()">
        <option default value="">Reset</option>
        <option value="purple">Purple</option>
        <option value="yellow">Yellow</option>
        <option value="cyan">Cyan</option>
        <option value="fuchsia">Fuchsia</option>
        <option value="antiquewhite">Antique White</option>
        <option value="black">Black</option>
    </select><br>
    <button onclick="{document.getElementById('bsx').value=0; document.getElementById('bsy').value=0; document.getElementById('bsblur').value=0;
document.getElementById('bscolor').options[0].selected='selected';
changeBoxShadow('clear');}">Reset</button>
    
    
<hr>Transformations:
    <br>Set SkewX:
    <input type="range" value="0" min="-40" max="40" onChange="changeStyle(this, 'skewx', '', 'skewx(' + this.value + 'deg)')" />
    <button onclick="{changeStyle(this, 'skewx', '', 'clear'); this.previousSibling.value=0;}">Reset</button>
    <br>Set SkewY:
    <input type="range" value="0" min="-40" max="40" onChange="changeStyle(this, 'skewy', '', 'skewy(' + this.value + 'deg)')" />
    <button onclick="{changeStyle(this, 'skewy', '', 'clear'); this.previousSibling.value=0;}">Reset</button>
    <br>Set RotateX:
    <input type="range" value="0" min="-180" max="180" onChange="changeStyle(this, 'rotatex', '', 'rotatex(' + this.value + 'deg)')" />
    <button onclick="{changeStyle(this, 'rotatex', '', 'clear'); this.previousSibling.value=0;}">Reset</button>
    <br>Set RotateY:
    <input type="range" value="0" min="-180" max="180" onChange="changeStyle(this, 'rotatey', '', 'rotatey(' + this.value + 'deg)')" />
    <button onclick="{changeStyle(this, 'rotatey', '', 'clear'); this.previousSibling.value=0;}">Reset</button>
    <br>Set RotateZ:
    <input type="range" value="0" min="-180" max="180" onChange="changeStyle(this, 'rotatez', '', 'rotatez(' + this.value + 'deg)')" />
    <button onclick="{changeStyle(this, 'rotatez', '', 'clear'); this.previousSibling.value=0;}">Reset</button>     
    <br>Set TranslateX:
    <input type="range" value="0" min="-100" max="400" onChange="changeStyle(this, 'translatex', '', 'translatex(' + this.value + 'px)')" />
    <button onclick="{changeStyle(this, 'translatex', '', 'clear'); this.previousSibling.value=0;}">Reset</button> 
    <br>Set TranslateY:
    <input type="range" value="0" min="-100" max="400" onChange="changeStyle(this, 'translatey', '', 'translatey(' + this.value + 'px)')" />
    <button onclick="{changeStyle(this, 'translatey', '', 'clear'); this.previousSibling.value=0;}">Reset</button> 
    <br>Set TranslateZ:
    <input  type="range" value="0" min="-100" max="400" onChange="changeStyle(this, 'translatez', '', 'translatez(' + this.value + 'px)')" />
    <button onclick="{changeStyle(this, 'translatez', '', 'clear'); this.previousSibling.value=0;}">Reset</button> 
    <br>Set ScaleX:
    <input type="range" step="0.1" value="0" min="-5" max="5" onChange="changeStyle(this, 'scalex', '', 'scalex(' + this.value + ')')" />
    <button onclick="{changeStyle(this, 'scalex', '', 'clear'); this.previousSibling.value=0;}">Reset</button>
    <br>Set ScaleY:
    <input type="range" step="0.1" value="0" min="-5" max="5" onChange="changeStyle(this, 'scaley', '', 'scaley(' + this.value + ')')" />
    <button onclick="{changeStyle(this, 'scaley', '', 'clear'); this.previousSibling.value=0;}">Reset</button>        
    <br>Set Perspective:
    <input type="range" value="0" min="-100" max="100" onChange="changeStyle(this, 'perspective', '', 'perspective(' + this.value + 'px)')" />
    <button onclick="{changeStyle(this, 'perspective', '', 'clear'); this.previousSibling.value=0;}">Reset</button> 
</div>
<br>Class A Style: "<span id="classStyleA"></span>"
<br>Class B Style: "<span id="classStyleB"></span>"
<br>Class C Style: "<span id="classStyleC"></span>"
<br>Current String: "<span id="currentString"></span>"
// by Troy Whorten Feb 26, 2014
function changeBoxShadow(clear, text) {
    //get the class to apply the style change to
    var styleClassSel = document.getElementById("classSelect");
    var styleClass = styleClassSel[styleClassSel.selectedIndex].value;
    var ssting="";
    //get all the boxes of the selected class
    var boxes = document.querySelectorAll(styleClass);
    
    if(!text)
    {
        sx = "bsx";
        sy = "bsy";
        sb = "bsblur";
        sc = "bscolor";
        prop = "boxShadow";
    }
    else
    {
        sx = "tsx";
        sy = "tsy";
        sb = "tblur";
        sc = "tcolor";
        prop = "textShadow";
    }       
    
    //get values
    var xoff = document.getElementById(sx).value;     
    var yoff = document.getElementById(sy).value;
    var blur = document.getElementById(sb).value;
    var color = document.getElementById(sc).options[document.getElementById(sc).selectedIndex].value;
    
    if(!clear && color == "")
        color = "black";
    
    if(!clear)
        sstring = xoff + "px " + yoff + "px " + blur + "px " + color;
    else
        sstring = "";
    
    for (var i = 0; i < boxes.length; i++) {
        string = "boxes[i].style."+ prop +" ='" + sstring + "'";
        document.getElementById("currentString").innerHTML = string;
        eval(string);
    }
}


function changeStyle(el, prop, unit, trans) {
    //get the class to apply the style change to
    var styleClassSel = document.getElementById("classSelect");
    var styleClass = styleClassSel[styleClassSel.selectedIndex].value;
    var style;
    var string;

    //get the value of the style that changed
    if (el.tagName == "SELECT") style = el[el.selectedIndex].value;
    else style = el.value;

    //if style is undefined, make it blank
    if (!style) style = "";

    //if unit is undefined, make it blank
    if (!unit) unit = "";

    //get all the boxes of the selected class
    var boxes = document.querySelectorAll(styleClass);

    //apply the style change for non-transforms
    if (!trans) for (var i = 0; i < boxes.length; i++) {
        string = "boxes[i].style." + prop + "='" + style + unit + "'";
        document.getElementById("currentString").innerHTML = string;
        eval(string);
    }

    //apply transform styling
    if (trans) for (var i = 0; i < boxes.length; i++) {
        var transText;
        var curTrans;
        if (trans == "clear") trans = "";

        // browser feature detection      
        if (boxes[i].style.Transform === "" || boxes[i].style.Transform) {
            curTrans = boxes[i].style.Transform.toLowerCase();
            string = "boxes[i].style.transform";
        }
        if (boxes[i].style.webkitTransform === "" || boxes[i].style.webkitTransform) {
            curTrans = boxes[i].style.webkitTransform.toLowerCase();
            string = "boxes[i].style.webkitTransform";
        }
        if (boxes[i].style.oTransform === "" || boxes[i].style.oTransform) {
            curTrans = boxes[i].style.oTransform.toLowerCase();
            string = "boxes[i].style.oTransform";
        }

        var inString = curTrans.search(prop.toLowerCase());

        //alert("inString = " + inString);
        // if we find this transformation, find the end, cut it out
        if (inString != -1) {
            var cutEnd = curTrans.substr(inString).search(/[)]/i);
            transText = curTrans.substr(0, inString) + curTrans.substr(inString + cutEnd + 1);
        } else transText = curTrans;

        //append prop to transformation string if trans isn't empty
        if (trans) transText = transText + " " + trans;

        string = string + '="' + transText + '"';
        document.getElementById("currentString").innerHTML = string;
        eval(string);
    }

    // display the applied styling in the appropriate span
    var abox = document.querySelector(".a");
    var bbox = document.querySelector(".b");
    var cbox = document.querySelector(".c");
    document.getElementById("classStyleA").innerHTML = abox.style.cssText;
    document.getElementById("classStyleB").innerHTML = bbox.style.cssText;
    document.getElementById("classStyleC").innerHTML = cbox.style.cssText;
}

function clearAll() {
    var boxes = document.querySelectorAll('.box');
    for (var i = 0; i < boxes.length; i++) {
        string = 'boxes[i].setAttribute("style","")';
        document.getElementById("currentString").innerHTML = string;
        eval(string);
    }
    
    // display the applied styling in the appropriate span
    var abox = document.querySelector(".a");
    var bbox = document.querySelector(".b");
    var cbox = document.querySelector(".c");
    document.getElementById("classStyleA").innerHTML = abox.style.cssText;
    document.getElementById("classStyleB").innerHTML = bbox.style.cssText;
    document.getElementById("classStyleC").innerHTML = cbox.style.cssText;
}
.container, .controls {
    border-style:dotted;
    border-width:1px;
    width: 420px;
    height: 420px;
    position: relative;
    display: inline-block;
    vertical-align: top;
    overflow: scroll;
}

.controls {
    width: 300px;
}

.box {
    width: 80px;
    height: 80px;
    color: white;
    text-align: center;
    overflow: hidden;
}
.a {
    background-color: blue;
}
.b {
    background-color: red;
}
.c {
    background-color: green;
}

.resetall {
    float:right;
}