Overleaf/services/web/public/stylesheets/less/intro.less

.introjs-overlay {
  position: absolute;
  z-index: 999999;
  background-color: #000;
  opacity: 0;
  background: -moz-radial-gradient(center,ellipse cover,rgba(0,0,0,0.4) 0,rgba(0,0,0,0.9) 100%);
  background: -webkit-gradient(radial,center center,0px,center center,100%,color-stop(0%,rgba(0,0,0,0.4)),color-stop(100%,rgba(0,0,0,0.9)));
  background: -webkit-radial-gradient(center,ellipse cover,rgba(0,0,0,0.4) 0,rgba(0,0,0,0.9) 100%);
  background: -o-radial-gradient(center,ellipse cover,rgba(0,0,0,0.4) 0,rgba(0,0,0,0.9) 100%);
  background: -ms-radial-gradient(center,ellipse cover,rgba(0,0,0,0.4) 0,rgba(0,0,0,0.9) 100%);
  background: radial-gradient(center,ellipse cover,rgba(0,0,0,0.4) 0,rgba(0,0,0,0.9) 100%);
  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#66000000',endColorstr='#e6000000',GradientType=1);
  -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=50)";
  filter: alpha(opacity=50);
  -webkit-transition: all 0.3s ease-out;
     -moz-transition: all 0.3s ease-out;
      -ms-transition: all 0.3s ease-out;
       -o-transition: all 0.3s ease-out;
          transition: all 0.3s ease-out;
}

.introjs-fixParent {
  z-index: auto !important;
}

.introjs-showElement {
  z-index: 9999999 !important;
}

.introjs-relativePosition {
  position: relative;
}

.introjs-helperLayer {
  position: absolute;
  z-index: 9999998;
  background-color: #FFF;
  background-color: rgba(255,255,255,.9);
  border: 1px solid #777;
  border: 1px solid rgba(0,0,0,.5);
  border-radius: 4px;
  box-shadow: 0 2px 15px rgba(0,0,0,.4);
  -webkit-transition: all 0.3s ease-out;
     -moz-transition: all 0.3s ease-out;
      -ms-transition: all 0.3s ease-out;
       -o-transition: all 0.3s ease-out;
          transition: all 0.3s ease-out;
}

.introjs-helperNumberLayer {
  position: absolute;
  top: -16px;
  left: -16px;
  z-index: 9999999999 !important;
  padding: 2px;
  font-family: Arial, verdana, tahoma;
  font-size: 13px;
  font-weight: bold;
  color: white;
  text-align: center;
  text-shadow: 1px 1px 1px rgba(0,0,0,.3);
  background: #ff3019; /* Old browsers */
  background: -webkit-linear-gradient(top, #ff3019 0%, #cf0404 100%); /* Chrome10+,Safari5.1+ */
  background: -webkit-gradient(linear, left top, left bottom, color-stop(0%, #ff3019), color-stop(100%, #cf0404)); /* Chrome,Safari4+ */
  background:    -moz-linear-gradient(top, #ff3019 0%, #cf0404 100%); /* FF3.6+ */
  background:     -ms-linear-gradient(top, #ff3019 0%, #cf0404 100%); /* IE10+ */
  background:      -o-linear-gradient(top, #ff3019 0%, #cf0404 100%); /* Opera 11.10+ */
  background:         linear-gradient(to bottom, #ff3019 0%, #cf0404 100%);  /* W3C */
  width: 20px;
  height:20px;
  line-height: 20px;
  border: 3px solid white;
  border-radius: 50%;
  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ff3019', endColorstr='#cf0404', GradientType=0); /* IE6-9 */ 
  filter: progid:DXImageTransform.Microsoft.Shadow(direction=135, strength=2, color=ff0000); /* IE10 text shadows */
  box-shadow: 0 2px 5px rgba(0,0,0,.4);
}

.introjs-arrow {
  border: 5px solid white;
  content:'';
  position: absolute;
}
.introjs-arrow.top {
  top: -10px;
  border-top-color:transparent;
  border-right-color:transparent;
  border-bottom-color:white;
  border-left-color:transparent;
}
.introjs-arrow.right {
  right: -10px;
  top: 10px;
  border-top-color:transparent;
  border-right-color:transparent;
  border-bottom-color:transparent;
  border-left-color:white;
}
.introjs-arrow.bottom {
  bottom: -10px;
  border-top-color:white;
  border-right-color:transparent;
  border-bottom-color:transparent;
  border-left-color:transparent;
}
.introjs-arrow.left {
  left: -10px;
  top: 10px;
  border-top-color:transparent;
  border-right-color:white;
  border-bottom-color:transparent;
  border-left-color:transparent;
}

.introjs-tooltip {
  position: absolute;
  padding: 10px;
  background-color: white;
  min-width: 200px;
  max-width: 300px;
  border-radius: 3px;
  box-shadow: 0 1px 10px rgba(0,0,0,.4);
  -webkit-transition: opacity 0.1s ease-out;
     -moz-transition: opacity 0.1s ease-out;
      -ms-transition: opacity 0.1s ease-out;
       -o-transition: opacity 0.1s ease-out;
          transition: opacity 0.1s ease-out;
}

.introjs-tooltipbuttons {
  text-align: right;
}

/* 
 Buttons style by http://nicolasgallagher.com/lab/css3-github-buttons/ 
 Changed by Afshin Mehrabani
*/
.introjs-button {
  position: relative;
  overflow: visible;
  display: inline-block;
  padding: 0.3em 0.8em;
  border: 1px solid #d4d4d4;
  margin: 0;
  text-decoration: none;
  text-shadow: 1px 1px 0 #fff;
  font: 11px/normal sans-serif;
  color: #333;
  white-space: nowrap;
  cursor: pointer;
  outline: none;
  background-color: #ececec;
  background-image: -webkit-gradient(linear, 0 0, 0 100%, from(#f4f4f4), to(#ececec));
  background-image: -moz-linear-gradient(#f4f4f4, #ececec);
  background-image: -o-linear-gradient(#f4f4f4, #ececec);
  background-image: linear-gradient(#f4f4f4, #ececec);
  -webkit-background-clip: padding;
  -moz-background-clip: padding;
  -o-background-clip: padding-box;
  /*background-clip: padding-box;*/ /* commented out due to Opera 11.10 bug */
  -webkit-border-radius: 0.2em;
  -moz-border-radius: 0.2em;
  border-radius: 0.2em;
  /* IE hacks */
  zoom: 1;
  *display: inline;
  margin-top: 10px;
}

.introjs-button:hover {
  border-color: #bcbcbc;
  text-decoration: none; 
  box-shadow: 0px 1px 1px #e3e3e3;
}

.introjs-button:focus,
.introjs-button:active {
  background-image: -webkit-gradient(linear, 0 0, 0 100%, from(#ececec), to(#f4f4f4));
  background-image: -moz-linear-gradient(#ececec, #f4f4f4);
  background-image: -o-linear-gradient(#ececec, #f4f4f4);
  background-image: linear-gradient(#ececec, #f4f4f4);
}

/* overrides extra padding on button elements in Firefox */
.introjs-button::-moz-focus-inner {
  padding: 0;
  border: 0;
}

.introjs-skipbutton {
  margin-right: 5px;
  color: #7a7a7a;
}

.introjs-prevbutton {
  -webkit-border-radius: 0.2em 0 0 0.2em;
  -moz-border-radius: 0.2em 0 0 0.2em;
  border-radius: 0.2em 0 0 0.2em;
  border-right: none;
}

.introjs-nextbutton {
  -webkit-border-radius: 0 0.2em 0.2em 0;
  -moz-border-radius: 0 0.2em 0.2em 0;
  border-radius: 0 0.2em 0.2em 0;
}

.introjs-disabled, .introjs-disabled:hover, .introjs-disabled:focus {
  color: #9a9a9a;
  border-color: #d4d4d4;
  box-shadow: none;
  cursor: default;
  background-color: #f4f4f4;
  background-image: none;
  text-decoration: none;
}