From Arcanet
.contentwarning{ color:crimson; margin: 5px; } .spoilertext{ color:black; background-color:black; padding-left: 2px; padding-right: 2px; } .spoilertext:hover{ color:white; } .spoilerimage{ position: relative; display: inline-block; overflow: hidden; } .spoilerimage img{ filter:blur(50px); } .spoilerimage img:hover{ filter:blur(0px); } .spoilerimage #warning{ position: absolute; top: 50%; left: 1%; width: 97.5%; text-align: center; background-color: darkslategray; border: groove 2px darkslategray; border-radius: 1em; } .spoilerimage:hover #warning{ display:none; }