tootlab-mastodon/app/javascript/styles/mastodon/reset.scss

/* http://meyerweb.com/eric/tools/css/reset/
   v2.0 | 20110126
   License: none (public domain)
*/

html, body, div, span, applet, object, iframe,
h1, h2, h3, h4, h5, h6, p, blockquote, pre,
a, abbr, acronym, address, big, cite, code,
del, dfn, em, img, ins, kbd, q, s, samp,
small, strike, strong, sub, sup, tt, var,
b, u, i, center,
dl, dt, dd, ol, ul, li,
fieldset, form, label, legend,
table, caption, tbody, tfoot, thead, tr, th, td,
article, aside, canvas, details, embed,
figure, figcaption, footer, header, hgroup,
menu, nav, output, ruby, section, summary,
time, mark, audio, video {
  margin: 0;
  padding: 0;
  border: 0;
  font-size: 100%;
  font: inherit;
  vertical-align: baseline;
}

/* HTML5 display-role reset for older browsers */
article, aside, details, figcaption, figure,
footer, header, hgroup, menu, nav, section {
  display: block;
}

body {
  line-height: 1;
}

ol, ul {
  list-style: none;
}

blockquote, q {
  quotes: none;
}

blockquote:before, blockquote:after,
q:before, q:after {
  content: '';
  content: none;
}

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

@supports not selector(::-webkit-scrollbar) {
  html {
    scrollbar-color: $action-button-color var(--background-border-color);
    scrollbar-width: thin;
  }
}

::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-thumb {
  background-color: $action-button-color;
  border: 2px var(--background-border-color);
  border-radius: 12px;
  width: 6px;
  box-shadow: inset 0 0 0 2px var(--background-border-color);
}

::-webkit-scrollbar-track {
  background-color: var(--background-border-color);
  border-radius: 0px;
}

::-webkit-scrollbar-corner {
  background: transparent;
}