The Power of CSS

Cool Things To Do With Styles

Assumption:

Coverage >95%

(Sorry IE 6-9 and Opera Mini!)

 

https://caniuse.com/

Pseudo Elements

Creates elements that do not exist in the document

::after
::before
::first-line
::selection
::placeholder

 

Pseudo Classes

Changes the display of existing elements


:focus
:hover
:checked
:only-of-type

::before & ::after

.comment-body::before {
    border-width: 0 15px 15px 0;
    border-color: 
        transparent
        rgba(158, 158, 158, 0.33);
    border-style: solid;
    content: '';
    display: block;
    left: -17px;
    position: absolute;
    top: 35px;
}

.bypostauthor > .comment-body::before {
    border-color: 
        transparent
        rgba(158, 158, 158, 1);
}

:first-child

.alignfull {
    margin: 2em calc(50% - 50vw);
}
.wp-block-cover:first-child {
	margin-top: 0;
}

:last-of-type

p {
    margin-bottom: 2em;
}
.comment-content p:last-of-type {
	margin-bottom: 0;
}

:not()

.comment.parent 
  .comment-body::after,
.comment.parent .children 
 .comment:not(:last-child)::after {
    border-left: 
      2px dashed rgba(158, 158, 158, 0.15);
    content: '';
    display: block;
    height: 100%;
    left: -48px;
    position: absolute;
    top: 56px;
    width: 2px;
}

Properties

Content:

ul > li::after {
  content: ", ";
}
ul > li:not(:last-child):after {
  content: ", ";
}

object-fit:

.wp-block-gallery img {
    width: 180px;
    height: 120px;
}
.wp-block-gallery img {
    width: 180px;
    height: 120px;
    object-fit: contain;
}
.wp-block-gallery img {
    width: 180px;
    height: 120px;
    object-fit: cover;
}

background-origin:

background-origin: content-box;

Animation

<div class="typewriter">
  <h1>WP Y'all!!!</h1>
</div>

.typewriter h1 {
  font-family: monospace;
  overflow: hidden;
  border-right: .15em solid orange;
  white-space: nowrap;
  margin: 0 auto;
  letter-spacing: .15em;
  animation: 
    typing 3.5s steps(30, end),
    blink-caret .5s step-end infinite;
}
/* The typing effect */
@keyframes typing {
  from { width: 0 }
  to { width: 100% }
}
/* The typewriter cursor effect */
@keyframes blink-caret {
  from, to { border-color: transparent }
  50% { border-color: orange }
}

Thank You WordCamp US!