jQuery accessible simple tooltip window, using ARIA

<h3>First simple example</h3>
<p>
    <button class="js-simple-tooltip"
 data-simpletooltip-text="Cool, it works!">
  Hover or focus me to show the tooltip
</button>
</p>

<h3>Second simple example</h3>
<button class="js-simple-tooltip"
 data-simpletooltip-content-id="tooltip-case_1">
  Show me another tooltip
</button>
<div id="tooltip-case_1" class="hidden">Woot, you can take the content of a hidden block.</div>

.hidden {
    display: none;
}
/* it will work better with this box-sizing, you may adapt it to your needs */
html { box-sizing: border-box; }
*, *:before, *:after {
  box-sizing: inherit;
}

/* Tooltip hidden by default */
.simpletooltip[aria-hidden="true"],
.minimalist-simpletooltip[aria-hidden="true"],
.minimalist-left-simpletooltip[aria-hidden="true"] {
  display: none;
}
/* position relative for containers */
.simpletooltip_container,
.minimalist-simpletooltip_container,
.minimalist-left-simpletooltip_container {
  position: relative;
  display: inline;
}

/* tooltip styles */
.simpletooltip,
.minimalist-simpletooltip,
.minimalist-left-simpletooltip {
  position: absolute;
  display: inline-block;
  z-index: 666;
  width: 10em;
  border-radius: .5em;
  background: rgba( 0, 0, 0, .9 );
  color: #eee;
  padding: .5em;
  text-align: left;
  line-height: 1.3;
}
.simpletooltip,
.minimalist-simpletooltip {
  right: auto;
  left: 100%;
  margin-left: .5em;
}
.minimalist-left-simpletooltip {
  right: 100%;
  left: auto;
  margin-right: .5em;
}
/* used pseudo-element to make arrows */
.simpletooltip::before,
.minimalist-simpletooltip::before,
.minimalist-left-simpletooltip::before {
  content: '';
  speak: none;
  position: absolute;
  z-index: 666;
  width: 10px;
  height: 10px;
}
.simpletooltip::before,
.minimalist-simpletooltip::before {
  top: .5em;
  left: -10px;
  margin-left: -10px;
  border: 10px solid transparent;
  border-right: 10px solid rgba( 0, 0, 0, .9 );
}
.minimalist-left-simpletooltip::before {
  top: .5em;
  right: -10px;
  margin-right: -10px;
  border: 10px solid transparent;
  border-left: 10px solid rgba( 0, 0, 0, .9 )
}

/* it can be easily adapted in media-queries for tablets/mobile */

/* for this example: mobile */
@media (max-width: 44.375em) {

  .simpletooltip,
  .minimalist-simpletooltip,
  .minimalist-left-simpletooltip  {
    top: 100%;
    left: 50%;
    right: 0;
    margin: 0;
    margin-top: .7em;
    margin-left: -5em;
  }
  .simpletooltip::before,
  .minimalist-simpletooltip::before,
  .minimalist-left-simpletooltip::before  {
    top: -10px;
    right: auto;
    left: 50%;
    margin-left: -5px;
    margin-top: -10px;
    border: 10px solid transparent;
    border-bottom: 10px solid rgba( 0, 0, 0, .9 );
  }

}