cutereset.css

html {
  box-sizing: border-box;
  -webkit-tap-highlight-color: transparent;
}

*,
*:before,
*:after {
  box-sizing: inherit;
}

ul, ol {
  padding-left: 1em;
}

img {
  max-width: 100%;
  height: auto;
}

* {
  margin: 0;
  padding: 0;
  position: relative;
  text-rendering: optimizeLegibility;
}

.flex {
  display: flex;
}

.flex-direction-column {
  flex-direction: column;
}

.flex-1 {
  flex: 1;
}

.flex-2 {
  flex: 2;
}

.flex-align-center {
  align-items: center;
}

.flex-align-start {
  align-items: flex-start;
}

.flex-align-stretch {
  align-items: stretch;
}

.flex-content-center {
  flex-content: center;
}

.flex-justify-center {
  justify-content: center;
}

h1, h2, h3, h4, h5, h6 {
  line-height: 1.127;
  margin-top: 0;
  margin-bottom: 0.309rem;
}

h1 {
  font-size: 4.23em;
}

h2 {
  font-size: 2.617em;
}

h3 {
  font-size: 1.618em;
}

h4 {
  font-size: 1.272em;
}

h5 {
  font-size: 1.127em;
}