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Add External Stylesheets/Pens

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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.


<p id="btn">続きを読む…</p>
<div id="box">
  <p> 泳ぎが得意であり、水中での生活に適応している。また、ラッコ以外のカワウソは陸上でも自由に行動している。南極、オーストラリア、ニュージーランドを除く、世界全域の水辺や海上で生息している。水かきをもった四肢は短く、胴体は細長い。このような体型は水の抵抗が少なく、敏捷な泳ぎを可能にしている。</p>
              $color: #1EA6BB;
  width: 500px;
  margin: 0 auto;
  padding: 20px;
  background: $color;
  color: #fff;
  cursor: pointer;
    background: lighten($color, 3%);
  display: none;
  overflow: hidden;
  height: 0;
              window.onload = function(){  

var btn = document.getElementById('btn') ;
var box = document.getElementById('box') ;  
var copyBox = box.cloneNode(true);
copyBox.style.cssText = "display:block; height:auto; visibility:hidden; " ;
var copyBoxH = copyBox.offsetHeight;

btn.onclick = function(){
    var boxH = box.offsetHeight;
    if(boxH < 1){
        box.style.display = "block";
    } else {

var slideDown_timer;
function slideDown(boxH){
    if (boxH < copyBoxH) {
        var boxH = boxH + 5;
        box.style.height = boxH + "px";
        slideDown_timer = setTimeout(function(){slideDown(boxH)},5);
    } else {
        box.style.height = copyBoxH;

var slideUp_timer;
function slideUp(boxH){
    if (boxH >= 1) {
        var boxH = boxH - 5;
        box.style.height = boxH + "px";
        slideUp_timer = setTimeout(function(){slideUp(boxH)}, 5);
    } else {
        box.style.height = 0;
        box.style.display = "none";

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