once-campfire/app/assets/stylesheets/sidebar.css

/* Sidebar */
:root {
  --sidebar-inline-space: max(calc(var(--inline-space) * 1.5), 1vw);
  --sidebar-tools-height: calc(var(--block-space) + var(--btn-size) + (var(--block-space) * 2));
}

.sidebar__container {
  block-size: 100dvh;
  max-block-size: 100dvh;
  padding-block-end: var(--sidebar-tools-height);
}

.sidebar__tools {
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  inset: auto 0 0 0;
  padding-block: calc(var(--block-space) * 1.5);
  padding-inline: var(--sidebar-inline-space);
  position: fixed;

  @media (min-width: 100ch) {
    inline-size: calc(var(--sidebar-width));
    inset-inline-start: auto;
  }
}

.sidebar__toggle {
  inset-block-start: var(--block-space-half);
  inset-inline-start: calc((var(--btn-size) + max(var(--inline-space), 1vw)) * -1);
  position: absolute;
  transition:
    inset-inline-start 300ms ease,
    border-color 300ms ease,
    background-color 300ms ease;
  z-index: 5;

  #sidebar:where(:not(.open):has(.unread)) & {
    &::after {
      --size: 1em;

      aspect-ratio: 1;
      background-color: var(--color-negative);
      block-size: var(--size);
      border-radius: calc(var(--size) * 2);
      content: "";
      flex-shrink: 0;
      inline-size: var(--size);
      inset-block-start: calc(var(--size) / -4);
      inset-inline-end: calc(var(--size) / -4);
      position: absolute;
    }
  }

  @media (min-width: 100ch) {
    display: none;
    inset-block-start: var(--block-space);
  }

  .open & {
    inset-block-start: var(--block-space);

    @media (max-width: 100ch) {
      inset-inline-start: var(--sidebar-inline-space);

      & img {
        filter: invert(0);
      }

      @media (prefers-color-scheme: dark) {
        & img {
          filter: invert(100%);
        }
      }
    }
  }
}

/* Direct messsages */
.directs {
  --btn-border-color: var(--color-border-darker);
  --column-gap: calc(var(--inline-space) / 1.5);

  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  display: grid;
  grid-auto-columns: minmax(auto, max-content);
  grid-auto-flow: column;
  inset: 0 0 auto 0;
  justify-content: start;
  overscroll-behavior: auto;
  margin-block-end: var(--block-space-half);
  padding-block: var(--block-space) var(--block-space-half);
  padding-inline: var(--sidebar-inline-space) calc(var(--sidebar-inline-space) + var(--column-gap));
  position: sticky;
  z-index: 3;

  .open & {
    @media (max-width: 100ch) {
      -webkit-mask-image: linear-gradient(to left, oklch(0% 0 0 / 1) 85%, oklch(0% 0 0 / 0) 99%);
      mask-image: linear-gradient(to left, oklch(0% 0 0 / 1) 85%, oklch(0% 0 0 / 0) 99%);
      padding-inline-start: calc(var(--btn-size) + var(--sidebar-inline-space) + (var(--column-gap) * 2.5));
    }
  }

  &.directs--new {
    --column-gap: var(--inline-space);
    --row-gap: 2px;

    -webkit-mask-image: none;
    mask-image: none;
    padding-inline-end: var(--sidebar-inline-space);
  }
}

.directs--edit  {
  display: grid;
  gap: var(--inline-space);
  grid-template-columns: repeat(auto-fit, minmax(33%, 1fr));
  grid-template-rows: min-content;
  place-items: center;

  .member {
    aspect-ratio: 1;
    block-size: auto;
    inline-size: 100%;
    margin-inline: auto;
    place-content: center;
  }
}

.direct {
  border-radius: 0.3em;
  box-shadow: none;
  color: var(--color-text);
  display: grid;
  justify-items: center;
  position: relative;
  text-decoration: none;

  .avatar,
  .avatar__group {
    margin-inline: calc(var(--inline-space) / 1.5);

    .avatar {
      margin-inline: 0;
    }
  }

  @media (any-hover: hover) {
    &:where(:not(:active):hover) .avatar:not(.avatar--icon) {
      filter: brightness(0.7);
    }
  }

  &:focus-within,
  &:where(:not(:active)):focus-visible {
    outline: 0;
  }
}

.direct__new {
  margin-inline-end: var(--inline-space-half);

  .avatar {
    margin-inline: 0;
  }
}

.direct__author {
  --column-gap: 0.3ch;

  margin-block-start: 0.1em;

  .unread & {
    font-weight: 800;
    position: relative;

    &::after {
      --size: 0.6em;

      aspect-ratio: 1;
      background-color: var(--color-text);
      block-size: var(--size);
      border-radius: calc(var(--size) * 2);
      content: "";
      flex-shrink: 0;
      inline-size: var(--size);
      position: absolute;
      inset: 1.3em auto auto 50%;
      transform: translate(-50%);
    }
  }
}

/* Rooms */
.rooms {
  --column-gap: 0.5em;
  --row-gap: 0.5em;

  padding-inline: var(--sidebar-inline-space);
}

.rooms__new-btn {
  inset-block-end: calc((var(--sidebar-tools-height) * -1) + var(--block-space) * 1.5);
  position: sticky;
  z-index: 4;
}

.room {
  background-color: var(--color-text-reversed);
  color: var(--color-text);
  font-weight: normal;
  justify-content: start;
  margin-inline-end: auto;
  max-inline-size: 100%;

  .searches-list & {
    border-radius: 0.5em;
  }

  &.unread {
    --btn-border-color: var(--color-text);
    --hover-color: var(--color-text);

    font-weight: 600;

    &:not(:hover) {
      box-shadow: 0 0 0 1px var(--color-text);
    }
  }
}

.room--current {
  --btn-border-radius: 0.5em;
  --hover-filter: none;
  --num-buttons: 1;

  min-block-size: var(--btn-size);

  .room__contents {
    .account-has-logo & {
      --num-buttons: 2;
    }

    max-inline-size: calc(100dvw - (var(--btn-size) * var(--num-buttons)) - (var(--btn-size) + max(var(--inline-space), 1vw)) - ((var(--inline-space) + 1.8em) * 2) - var(--sidebar-width) - var(--inline-space) * var(--num-buttons));

    @media (max-width: 100ch) {
      --num-buttons: 2;

      .account-has-logo & {
        --num-buttons: 3;
      }
    }
  }
}

/* Searches */
.searches {
  #nav {
    align-items: start;
    column-gap: 0;
    padding-inline-end: 0;
  }

  .rooms {
    padding-block-start: var(--block-space);
  }

  .message--formatted .message__room {
    display: block;
    font-size: 0.8rem;
    font-weight: 400;
    overflow: hidden;
    text-overflow: ellipsis;
    visibility: visible;
    white-space: nowrap;

    &::before {
      content: "→";
    }

    .message--me & {
      &::after {
        content: "←";
      }

      &::before {
        content: "";
      }
    }
  }

  .message__actions {
    display: none !important;
    visibility: hidden !important;
  }
}

.searches__recents {
  --mask: linear-gradient(to left, oklch(0% 0 0 / 1) 97%, oklch(0% 0 0 / 0) 99%);

  -webkit-mask-image: var(--mask);
  display: none;
  mask-image: var(--mask);
  position: relative;

  @media (max-width: 100ch) {
    display: flex;
  }

  .room {
    max-inline-size: 20ch;

    &:first-child {
      margin-inline-start: var(--inline-space);
    }
  }

  .searches__btn {
    margin-inline-end: var(--inline-space-double);
  }
}

.searches__query {
  --btn-border-radius: 0.5em;

  min-block-size: var(--btn-size);
}

.searches__results {
  padding-block-start: var(--navbar-height);
}

.searches__input:required:invalid {
  ~ .searches__reset {
    display: none;
    visibility: hidden;
  }
}