miaou-server/templates/nginx/snippets/banner_dev.conf

proxy_set_header Accept-Encoding "";

subs_filter '</body>' '
<div class="betabanner_box">
  <div class="betabanner_ribbon"><span>DEV</span></div>
</div>

<style>

.betabanner_box {
  height: 100%;
  position: absolute;
  bottom: 0;
  pointer-events: none;
  opacity: 0.7;          
}

.betabanner_ribbon {
  position: fixed;
  left: -5px; 
    bottom : 0;
  z-index: 9999;
  overflow: hidden;
  width: 75px; height: 75px;
  text-align: right;
}
.betabanner_ribbon span {
  font-size: 10px;
  font-weight: bold;
  color: #FFF;
  text-transform: uppercase;
  text-align: center;
  line-height: 20px;
  transform: rotate(45deg);
  -webkit-transform: rotate(45deg);
  width: 100px;
  display: block;
  background: linear-gradient(lightblue 30%, blue 81%);
  box-shadow: 5px 9px 27px -4px rgba(0, 0, 0, 1);

  position: absolute;
  bottom: 16px;
  left: -21px;
}
.betabanner_ribbon span::before {
  content: "";
  position: absolute; left: 0px; top: 100%;
  z-index: -1;
  border-left: 3px solid #79A70A;
  border-right: 3px solid transparent;
  border-bottom: 3px solid transparent;
  border-top: 3px solid #79A70A;
}
.betabanner_ribbon span::after {
  content: "";
  position: absolute; right: 0px; top: 100%;
  z-index: -1;
  border-left: 3px solid transparent;
  border-right: 3px solid #79A70A;
  border-bottom: 3px solid transparent;
  border-top: 3px solid #79A70A;
}
</style>
</body>
';