Custom stylesheet for social.ericwbailey.website. Perpetually a work in progress. https://ericwbailey.website/published/i-restyled-my-mastodon-instance/

mastodon.css

:root {
  --custom-border-radius: 999999px;
  --custom-color-background: #ffffff;
  --custom-color-background-panel: #f7f9fa;
  --custom-color-background-select: #616981;
  --custom-color-background-dm: #f7f7fe;
  --custom-color-background-focus: #e0e5eb;
  --custom-color-background-verified: #bdf7af;
  --custom-color-border-resting: #e0e5eb;
  --custom-color-border-active: #c2ccd8;
  --custom-color-border-poll-unvoted-resting: #616981;
  --custom-color-border-poll-unvoted-hover: #616981;
  --custom-color-border-poll-voted-resting: #282c36;
  --custom-color-border-poll-voted-hover: #282c36;
  --custom-color-button-resting: #6364ff;
  --custom-color-button-hover: #563acc;
  --custom-color-button-active: #3d2c91;
  --custom-color-border-error: #f45f45;
  --custom-color-border-notification-resting: #afb1f7;
  --custom-color-link-secondary-resting: #616981;
  --custom-color-text-primary: #282c36;
  --custom-color-text-verified: #4aa51a;
  --custom-color-text-secondary: #616981;
  --custom-color-text-select: #ffffff;
  --custom-color-fill-resting: #c2ccd8;
  --custom-color-fill-hover: #616981;
  --custom-color-fill-active: #282c36;
  --custom-font-size-medium: 15px;
  --custom-font-size-small: 14px;
  --custom-font-size-smallest: 12px;
  --custom-transition-short: 200ms;
  --custom-transition-shortest: 125ms;
}




/* 
  RESETS AND REMOVALS
*/
html {
  scrollbar-color: unset;
}

.column-header__wrapper.active {
  box-shadow: none;
}

.status__info abbr {
  text-decoration: none;
}

.column-header.active .column-header__icon {
  text-shadow: none;
}

:is(
  .app-body .navigation-panel__logo,
  .emoji-picker-dropdown,
  .link-footer,
  .navigation-panel [title="Bookmarks"],
  .navigation-panel [title="Favorites"],
  .navigation-panel [title="Lists"],
  [aria-label="Explore"] .explore__links .dismissable-banner
) {
  display: none;
}

@media screen and (width >= 320px) {
  .ui__header__logo .logo--wordmark {
    display: none;
  }
}

@media screen and (max-width: 1174px) {
  .columns-area__panels {
    min-height: calc(100vh - 0px);
  }
}



/*
  ADJUSTMENTS
*/
/* Backgrounds */
:is(
  html,
  body.theme-mastodon-light,
  .tabs-bar__wrapper,
  .account__section-headline,
  .detailed-status__wrapper-direct .detailed-status,
  .detailed-status__wrapper-direct .detailed-status__action-bar,
  .explore__search-results,
  .notification__filter-bar,
  .search-results__section__header,
  .search-results__section .account,
  .search-results__section .trends__item,
  .explore__search-results .account,
  .explore__search-results .trends__item
) {
  background-color: var(--custom-color-background);
}

@media screen and (max-width: 1174px) {
  .layout-single-column .ui__header,
  .columns-area__panels__pane--navigational .navigation-panel {
    background-color: var(--custom-color-background);
  }
}

:is(
  .column-header__collapsible-inner,
  .explore__search-header,
  .follow_requests-unlocked_explanation
) {
  background: var(--custom-color-background-panel);
}

:is(
  .conversation--unread,
  .status__wrapper-direct
) {
  background: var(--custom-color-background-dm);
}

.status__content .status__content__spoiler-link {
  background: var(--custom-color-background-panel);
  position: relative;
    top: 2px;
  transition: background var(--custom-transition-shortest) ease-in-out;
}

.status__content .status__content__spoiler-link:active {
  transition: none;
}

.column-header__wrapper.active::before {
  background: none;
}

/* Borders */
:is(
  .column-back-button,
  .column-header,
  .compose-form__poll-wrapper .button.button-secondary,
  .navigation-panel hr,
  .compose-panel .reply-indicator
) {
  border-color: var(--custom-color-border-resting);
}

@media screen and (max-width: 1174px) {
  .column-header {
    border-right-color: var(--custom-color-background) !important;
  }

  .navigation-panel hr {
    border-color: var(--custom-color-background) !important;
  }
}

:is(
  .account,
  .account__section-headline,
  .column-header__collapsible,
  .conversation,
  .follow_requests-unlocked_explanation,
  .load-gap,
  .status,
  .trends__item 
) {
  border-bottom-color: var(--custom-color-border-resting);
}

@media screen and (max-width: 1174px) {
  .layout-single-column .ui__header {
    border-bottom-color: var(--custom-color-background);
  }
}

.column-header__collapsible-inner {
  border-color: var(--custom-color-border-resting);
  border-right: none;
  border-left: none;
}

@media screen and (max-width: 1174px) {
  .column-header {
    border-right-color: var(--custom-color-background);
  }
}

.column > .scrollable {
  border: none;
}

.detailed-status {
  border-top-color: var(--custom-color-border-resting);
}

.detailed-status__action-bar {
  border-top-color: var(--custom-color-border-resting);
  border-bottom-color: var(--custom-color-border-resting);
}

.notification__filter-bar {
  border-right: none;
  border-bottom-color: var(--custom-color-border-resting);
  border-left: none;
}

.status__line {
  border-inline-start: 2px solid var(--custom-color-border-resting);
}

@media screen and (max-width: 1174px) {
  .columns-area__panels__pane--navigational .navigation-panel {
    border-inline-start: 1px solid var(--custom-color-background);
  }
}

.notification.unread::before, .status__wrapper.unread::before {
  border-inline-start: 1px solid var(--custom-color-border-notification-resting);
}




/* Inputs */
.search__input {
  background-color: var(--custom-color-background);
  border-color: var(--custom-color-border-resting);
  transition: 
    background-color var(--custom-transition-short) ease-in-out,
    border-color var(--custom-transition-short) ease-in-out;
}

.search__input:focus,
.search__input:hover {
  background-color: var(--custom-color-background);
  border-color: var(--custom-color-border-active);
}

.search__input:active {
  transition: none;
}

.search__popout {
  border: 1px solid var(--custom-color-border-active);
  box-shadow: none;
  background-color: var(--custom-color-background);
}

.compose-form .compose-form__autosuggest-wrapper {
  border-top-color: var(--custom-color-border-resting);
  border-right-color: var(--custom-color-border-resting);
  border-bottom-color: var(--custom-color-border-resting);
  border-left-color: var(--custom-color-border-resting);
  transition: border-color var(--custom-transition-short) ease-in-out;
}

.compose-form .compose-form__autosuggest-wrapper:hover {
  border-top-color: var(--custom-color-border-active);
  border-right-color: var(--custom-color-border-active);
  border-left-color: var(--custom-color-border-active);
}

.compose-form .compose-form__autosuggest-wrapper:focus-within {
  border-top-color: var(--custom-color-border-active);
  border-right-color: var(--custom-color-border-active);
  border-left-color: var(--custom-color-border-active);
}

.compose-form .compose-form__buttons-wrapper {
  border-color: var(--custom-color-border-resting);
}


/*
  MOBILE TWEAKS
*/
@media screen and (max-width: 1174px) {
  .tabs-bar__wrapper {
    position: initial;
  }

  .ui__header {
    height: 0;
    position: static;
  }

  .ui__header__links {
    position: fixed;
    top: 14px;
    right: 0;
  }

  .column-link[title="Home"] {
    margin-top: 50px;
  }

  .ui__header__links .account__avatar {
    --custom-mobile-avatar-size: 26px;

    height: var(--custom-mobile-avatar-size) !important;
    width: var(--custom-mobile-avatar-size) !important;
  }

  .ui__header__links [aria-label="Search"] {
    display: none;
  }

  .button.button-secondary[href="/publish"] {
    --custom-mobile-button-size: 30px;
    --custom-mobile-button-position: 8px;

    background: var(--custom-color-button-resting) url("data:image/svg+xml;base64,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") no-repeat center; /* Feather icon: edit */
    background-size: 16px;
    border-color: transparent;
    background-position-x: 10px;
    background-position-y: 8px;
    border-radius: var(--custom-border-radius);
    height: calc(var(--custom-mobile-button-size) + 5px);
    position: fixed;
      bottom: var(--custom-mobile-button-position);
      right: var(--custom-mobile-button-position);
    transition: background-color var(--custom-transition-short) ease-in-out;
    width: var(--custom-mobile-button-size);
  }

  .button.button-secondary[href="/publish"]:hover {
    background-color: var(--custom-color-button-hover);
  }

  .button.button-secondary[href="/publish"]:active {
    background-color: var(--custom-color-button-active);
    transition: none;
  }

  .button.button-secondary[href="/publish"] span {
    border: 0;
    clip: rect(0 0 0 0);
    height: 1px;
    margin: -1px;
    overflow: hidden;
    padding: 0;
    position: absolute;
    white-space: nowrap;
    width: 1px;
  }

  .columns-area__panels__main .status {
    padding-right: 8px;
    padding-left: 14px;
  }
}



/*
  ENHANCEMENTS
*/
.compose-form .compose-form__publish {
  padding-bottom: 20px;
}

/* Account card */
.explore__suggestions .account-card {
  margin: 30px 10px 10px 10px;
}

.scrollable .account-card {
  background-color: var(--custom-color-background);
  border: 1px solid var(--custom-color-border-resting);
}

.scrollable .account-card__bio::after {
  background: none;
}

.account-card__title__avatar .account__avatar {
  border-radius: var(--custom-border-radius);
}

/* Bio */
.account__header__fields,
.account__header__fields .verified {
  background: var(--custom-color-background) !important;
}

.account__header__fields dl {
  padding: 11px 16px 11px 0 !important;
  border-bottom-color: var(--custom-color-border-resting) !important;
}

.account__header__fields .verified {
  border-top-color: var(--custom-color-border-resting) !important;
  border-right: none !important;
  border-bottom-color: var(--custom-color-border-resting) !important;
  border-left: none !important;
}

.account__header__bio .account__header__fields .verified a,
.account__header__fields .verified__mark {
  color: var(--custom-color-text-verified);
}

.account__header__fields dl dt {
  color: var(--custom-color-text-secondary) !important;
  text-transform: initial !important;
}

/* Avatar and display name lockup */
.account__avatar,
.status__avatar {
  border-radius: var(--custom-border-radius);
}

.display-name span {
  bottom: 4px;
    position: relative;
  font-size: var(--custom-font-size-small);
}


/* Hamburger menu */
.compose__action-bar-dropdown [aria-label="Menu"] {
  transition: background-color var(--custom-transition-short) ease-in-out;
}

.compose__action-bar-dropdown [aria-label="Menu"]:active {
  transition: none;
}

/*  Load more */
.load-more {
  transition: background-color var(--custom-transition-short) ease-in-out;
}
.load-more:focus,
.load-more:hover {
  background-color: var(--custom-color-background-panel); 
}

@media screen and (max-width: 1174px) {
  .load-more:focus,
  .load-more:hover {
    background-color: var(--custom-color-background); 
  }
}

.load-more:active {
  transition: none;
}

/* Dropdowns */
.dropdown-menu__item a:hover, 
.dropdown-menu__item button:hover,
.privacy-dropdown__option.active, 
.privacy-dropdown__option:hover,
.language-dropdown__dropdown__results__item:hover,
.language-dropdown__dropdown__results__item.active,
.search__popout__menu__item.selected,
.search__popout__menu__item:hover {
  background: var(--custom-color-background-select) !important;
  color: var(--custom-color-text-select) !important;
}

.language-dropdown__dropdown__results__item .language-dropdown__dropdown__results__item__common-name {
  color: var(--custom-color-text-secondary);
}

.search__popout__menu__item.selected .icon-button,
.search__popout__menu__item:hover .icon-button {
  color: var(--custom-color-text-select) !important;
}

.language-dropdown__dropdown__results__item:hover .language-dropdown__dropdown__results__item__common-name,
.language-dropdown__dropdown__results__item.active .language-dropdown__dropdown__results__item__common-name {
  color: var(--custom-color-text-select) !important;
}

.dropdown-menu__separator {
  border-top-color: var(--custom-color-border-resting) !important;
}

.actions-modal .dropdown-menu__separator {
  border-bottom-color: var(--custom-color-border-resting) !important;
}


/* Profile edit */
.navigation-bar strong {
  font-size: var(--custom-font-size-medium);
  font-weight: bold;
}

.navigation-bar__profile-edit {
  color: var(--custom-color-link-secondary-resting) !important;
}

.navigation-bar__profile-edit span {
  position: relative;
    bottom: 3px
}

/* Reply meta */
.detailed-status__meta {
  opacity: 0.6;
  transition: opacity var(--custom-transition-short) ease-in-out;
}

.detailed-status__meta:hover {
  opacity: 1;
}

/* Buttons */
.button {
  transition: background-color var(--custom-transition-short) ease-in-out;
}

.button:active {
  background-color: var(--custom-color-button-active);
  transition: none !important;
}

/* Icon buttons */
.status__action-bar {
  justify-content: start;
}

.status__action-bar__dropdown {
  margin-left: auto;
}

.compose-form__buttons-wrapper [aria-label="Add images, a video or an audio file"],
.compose-form__buttons-wrapper [aria-label="Add a poll"],
.compose-form__buttons-wrapper [aria-label="Change post privacy"],
.compose-form__buttons-wrapper [aria-label="Add content warning"],
.compose-form__buttons-wrapper [aria-label="Change language"],
.status__action-bar [aria-label="Reply"],
.status__action-bar [aria-label="Reply to thread"],
.status__action-bar [aria-label="Boost"],
.status__action-bar [aria-label="Favorite"],
.status__action-bar [aria-label="More"],
.detailed-status__action-bar [aria-label="Reply"],
.detailed-status__action-bar [aria-label="Boost"],
.detailed-status__action-bar [aria-label="Favorite"],
.detailed-status__action-bar [aria-label="More"] {
  transition: background-color var(--custom-transition-short) ease-in-out;
}

.compose-form__buttons-wrapper [aria-label="Add images, a video or an audio file"]:active,
.compose-form__buttons-wrapper [aria-label="Add a poll"]:active,
.compose-form__buttons-wrapper [aria-label="Change post privacy"]:active,
.compose-form__buttons-wrapper [aria-label="Add content warning"]:active,
.compose-form__buttons-wrapper [aria-label="Change language"]:active,
.status__action-bar [aria-label="Reply"]:active,
.status__action-bar [aria-label="Reply to thread"]:active,
.status__action-bar [aria-label="Boost"]:active,
.status__action-bar [aria-label="Favorite"]:active,
.status__action-bar [aria-label="More"]:active,
.detailed-status__action-bar [aria-label="Reply"]:active,
.detailed-status__action-bar [aria-label="Reply to thread"]:active,
.detailed-status__action-bar [aria-label="Boost"]:active,
.detailed-status__action-bar [aria-label="Favorite"]:active,
.detailed-status__action-bar [aria-label="More"]:active {
  transition: none;
}

.status__action-bar [aria-label="Bookmark"],
.detailed-status__action-bar [aria-label="Bookmark"] {
  display: none;
}

.status__action-bar [aria-label="Reply"],
.status__action-bar [aria-label="Reply to thread"],
.status__action-bar [aria-label="Boost"],
.status__action-bar [aria-label="Favorite"],
.status__action-bar [aria-label="More"],
.detailed-status__action-bar [aria-label="Reply"],
.detailed-status__action-bar [aria-label="Boost"],
.detailed-status__action-bar [aria-label="Favorite"],
.detailed-status__action-bar [aria-label="More"] {
  filter: brightness(1.35);
  transition: filter var(--custom-transition-short) ease-in-out;
}

.status__action-bar [aria-label="Reply"]:hover,
.status__action-bar [aria-label="Reply to thread"]:hover,
.status__action-bar [aria-label="Boost"]:hover,
.status__action-bar [aria-label="Favorite"]:hover,
.status__action-bar [aria-label="More"]:hover,
.detailed-status__action-bar [aria-label="Reply"]:hover,
.detailed-status__action-bar [aria-label="Boost"]:hover,
.detailed-status__action-bar [aria-label="Favorite"]:hover,
.detailed-status__action-bar [aria-label="More"]:hover {
  filter: none;
}

/* Secondary text */
.display-name__account,
.status__relative-time,
.notification-follow .account__display-name .account__details,
.account__header__tabs__name small span,
.search-results__section .account__details {
  color: var(--custom-color-text-secondary);
}

.status__relative-time {
  position: relative;
    bottom: 2px;
}

.status__relative-time .status__visibility-icon,
.status__relative-time time,
.status__relative-time abbr {
  font-size: var(--custom-font-size-small) !important;
}

/* Polls */
.poll__input {
  border-color: var(--custom-color-border-poll-unvoted-hover);
}

.poll__input:hover {
  border-color: var(--custom-color-border-poll-unvoted-hover);
}

.poll__input.active {
  background-color: var(--custom-color-border-poll-unvoted-hover);
  border-color: var(--custom-color-border-poll-unvoted-hover);
}

/* Prepended statuses */
.status__prepend {
  font-size: var(--custom-font-size-small) !important;
  position: relative;
    right: 2px;
}

.status__prepend > span {
  position: relative;
    right: 7px;
}

.status__wrapper-direct .status__prepend > span {
  background-color: var(--custom-color-background-dm);
  z-index: 100;
}

.status__prepend,
.status__prepend .status__prepend-icon-wrapper i,
.status__prepend .status__display-name strong,
.status__prepend .status__display-name span {
  color: var(--custom-color-text-secondary) !important;
}

/* Status link cards */
a.status-card {
  border-color: var(--custom-color-border-resting) !important;
  transition: border-color var(--custom-transition-short) ease-in-out;
}

a.status-card:hover {
  border-color: var(--custom-color-border-active) !important;
}

a.status-card .status-card__title,
a.status-card:hover .status-card__title {
  color: var(--custom-color-text-primary) !important;
}

a.status-card .status-card__host,
a.status-card:hover .status-card__host,
a.status-card .status-card__author,
a.status-card:hover .status-card__author,
a.status-card .status-card__description, 
a.status-card:hover .status-card__description {
  color: var(--custom-color-text-secondary) !important;
}

.status-card__author {
  font-size: var(--custom-font-size-smallest);
}

a.status-card .status-card__host {
  margin-bottom: 0;
}

/* Banners */
.dismissable-banner {
  border: none;
}

/* Toot content */
.reply-indicator__content,
.status__content__text--visible {
  color: var(--custom-color-text-primary);
  line-height: 1.4;
  max-width: 52ch;
}

@media screen and (max-width: 1174px) {
  .reply-indicator__content,
  .status__content__text--visible {
    line-height: 1.3;
    max-width: unset;
  }
}

.hashtag-bar a,
.hashtag-bar button {
  color: var(--custom-color-text-secondary) !important;
}

.getting-started__trends h4 {
  color: var(--custom-color-text-secondary);
  text-transform: initial;
}

.getting-started__trends .trends__item__name span:nth-of-type(2) {
  color: var(--custom-color-text-secondary);
}

/* No alt text warning */
.media-gallery__gifv video:not([title]),
.media-gallery__gifv video[title=""],
.media-gallery__item-thumbnail img:not([alt]),
.media-gallery__item-thumbnail img[alt=""] {
  border: 2px solid var(--custom-color-border-error);
  box-sizing: border-box;
  border-radius: 3px;
  height: 99%;
  width: 99%;
}

Thanks for checking this out!

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