Libraries

Reset CSS

a {
    /*  inherit means having parent's color*/
    color: inherit; 
    text-decoration: none;
}

button:focus, button:active,
input:focus, input:active,
textarea:focus, textarea:active {
    box-shadow: none;
    outline:none;
}

ul, ol, li {
    list-style-type: none;
    padding-left: 0;
    margin-left: 0;
}

Modal

.backdrop {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100vh;
  z-index: 20;
  background-color: rgba(0, 0, 0, 0.75);
}

.modal {
  position: fixed;
  top: 20vh;
  left: 5%;
  width: 90%;
  background-color: white;
  padding: 1rem;
  border-radius: 14px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.25);
  z-index: 30;
  animation: slide-down 300ms ease-out forwards;
}

@media (min-width: 768px) {
  .modal {
    width: 40rem;
    left: calc(50% - 20rem);
  }
}

@keyframes slide-down {
  from {
    opacity: 0;
    transform: translateY(-3rem);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

bump animation

.bump {
  animation: bump 300ms ease-out;
}

@keyframes bump {
  0% {
    transform: scale(1);
  }
  10% {
    transform: scale(0.9);
  }
  30% {
    transform: scale(1.1);
  }
  50% {
    transform: scale(1.15);
  }
  100% {
    transform: scale(1);
  }
}

button:disabled

button:disabled, 
button:disabled:hover, 
button:disabled:active {
  cursor: not-allowed;
}

loading spinner

const LoadingSpinner = () => {
  return <div className={classes.spinner}></div>;
}

export default LoadingSpinner;

 

.spinner {
  display: inline-block;
  width: 80px;
  height: 80px;
}
.spinner:after {
  content: ' ';
  display: block;
  width: 64px;
  height: 64px;
  margin: 8px;
  border-radius: 50%;
  border: 6px solid teal;
  border-color: teal transparent teal transparent;
  animation: spinner 1.2s linear infinite;
}
@keyframes spinner {
  0% {
    transform: rotate(0deg);
  }
  100% {
    transform: rotate(360deg);
  }
}

+) 기타

Pure CSS Type-writer Effect with animation-timing-function