Reset stylesheet example. Uses PostCSS nesting.

reset.css

/*
  Reset text elements for easy semantic use.
  http://anthonyshort.me/global-typographic-styles-suck/
*/

/* Pseudo */

:focus {
  outline: none;
}

/* Lists */

ul,
ol,
dl,
li,
dt,
dd {
  margin: 0;
  padding: 0;
}

li {
  display: block;
  list-style: none;
}

/* Tables */

table {
  border-spacing: 0;
  border-collapse: collapse;
}

th {
  font-weight: inherit;
}

/* Forms */

form {
  margin: 0;
}

fieldset {
  margin: 0;
  padding: 0;
  border: 0;
}

button,
input,
select,
textarea {
  margin: 0;
  padding: 0;
  color: inherit;
  font-style: inherit;
  font-weight: inherit;
  font-size: 100%;
  font-family: inherit;
  vertical-align: baseline;
  background-color: transparent;
}

input[type="search"] {
  -webkit-appearance: textfield;
}

  &::-webkit-search-decoration {
    -webkit-appearance: none;
  }
}

/* Images */

figure {
  margin: 0;
}

/* Block level text */

h1,
h2,
h3,
h4,
h5,
h6 {
  margin: 0;
  font-weight: inherit;
  font-size: inherit;
  line-height: inherit;
}

p,
blockquote {
  margin: 0;
}

pre {
  margin: 0;
  font-size: inherit;
  font-family: inherit;
}

/* Links */

a {
  color: inherit;
  font-weight: inherit;
  text-decoration: none;

  &:hover,
  &:active,
  &:focus,
  &:visited {
    outline: none;
    text-decoration: none;
  }

  img {
    border: none;
  }
}

/* Other inline text */

cite {
  font-style: normal;
}

ins {
  text-decoration: none;
}

dfn {
  font-style: inherit;
}

del {
  text-decoration: none;
}

mark {
  color: inherit;
  background: none;
}

address {
  font-style: normal;
}

tt,
code,
kbd,
samp {
  font-size: inherit;
  font-family: inherit;
}

b,
strong {
  font-weight: inherit;
}

i,
em {
  font-style: inherit;
}

small {
  font-size: 100%;
}

q {
  quotes: none;

  &:before,
  &:after {
    content: "";
    content: none;
  }
}