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#b9b9b9;border-bottom-color:#939393;border-radius:4px;-moz-border-radius:4px;-webkit-border-radius:4px;cursor:pointer;margin-right:4px;width:65px;height:65px;text-align:center;font-size:1.2em;float:left;-webkit-user-select:none;-khtml-user-select:none;-moz-user-select:none;-o-user-select:none;user-select:none}.sortable>ul>li.placeholder{background:#ddd;border:0;border:1px solid #ccc;float:left}.sortable>ul>li .MathJax{line-height:65px}.sortable>ul>li:hover{border-color:#ffa500;box-shadow:0 0 4px #c56f00;-moz-box-shadow:0 0 4px #c56f00;-ms-box-shadow:0 0 4px #c56f00;-o-box-shadow:0 0 4px #c56f00;-webkit-box-shadow:0 0 4px #c56f00}.sortable>ul>li:active,.sortable>ul>li.dragging{background-color:#ffedcd;opacity:.8;filter:alpha(opacity = 80)}#want-more-hints{font-size:16px}#answer-feedback-container{padding:15px;border:2px solid #bf0000;position:absolute;border-radius:10px;background:white;top:0;box-shadow:0 2px #9b9b9b;transition:all .5s ease-in-out}#answer-feedback-container.hide-feedback{transform:translate(0,-50%);opacity:0}#answer-feedback-container span.arrow-bot,#answer-feedback-container span.arrow-top,#answer-feedback-container span.arrow-mid{width:0;height:0;font-size:0;overflow:hidden;position:absolute}#answer-feedback-container span.arrow-bot{border-width:20px;border-style:solid;border-color:#9b9b9b transparent transparent;left:45%;bottom:-42px}#answer-feedback-container span.arrow-mid{border-width:20px;border-style:solid;border-color:#bf0000 transparent transparent;left:45%;bottom:-40px}#answer-feedback-container span.arrow-top{border-width:20px;border-style:solid;border-color:#fff transparent transparent;left:45%;bottom:-38px}#answer-feedback-container img{width:24px;height:24px;margin-right:5px}#answer-feedback{margin-left:8px;white-space:nowrap}#energy-points{align-self:flex-end;display:none;color:#4a90e2;margin:0 auto}#feedback-text-container{display:flex;align-items:center;flex-grow:1}.login-required-card{line-height:500px;text-align:center}@media screen and (min-width:1024px){#timelinecontainer{border:1px solid #c6d1ad;position:relative;display:grid;grid-template-columns:repeat(2,1fr);grid-template-rows:1fr}#left-mask{top:0;left:226px}#timeline{left:225px;right:225px;border-left:1px solid #c6d1ad;border-right:1px solid #c6d1ad;grid-row:1/2}#right-mask{top:0;right:226px}#next-group{grid-row:1/2}}