metamask-extension/ui/app/pages/error/index.scss

.error-page {
  display: flex;
  flex-flow: column nowrap;
  align-items: center;
  font-style: normal;
  font-weight: normal;
  padding: 35px 10px 10px 10px;
  height: 100%;

  &__header {
    @include H1;

    display: flex;
    justify-content: center;
    padding: 10px 0;
    text-align: center;
  }

  &__subheader {
    @include H4;

    padding: 10px 0;
    width: 100%;
    max-width: 720px;
    text-align: center;
  }

  &__details {
    @include H4;

    overflow-y: auto;
    width: 100%;
    max-width: 720px;
    padding-top: 10px;
  }

  &__stack {
    overflow-x: auto;
    background-color: #eee;
  }
}