discourse_theme_ran/scss/composer-peek-mode.scss

.peek-mode-toggle {
  display: none;
}

@media screen and (width >= 1300px) {
  html:not(.fullscreen-composer) {
    .peek-mode-toggle svg {
      transform: scaleX(-1);
    }

    &.composer-open {
      .full-width-enabled .peek-mode-toggle {
        display: flex;
      }

      .full-width-enabled.peek-mode-active {
        #reply-control.hide-preview {
          transition: none;
          box-shadow: none;
          border-radius: var(--d-border-radius-large);

          .grippie {
            display: none;
          }

          .reply-area {
            padding-inline: 0.67em;
          }
        }

        #reply-control:not(.fullscreen).hide-preview {
          width: 100%;
          right: var(--main-grid-gap);
          top: var(--header-offset);
          bottom: var(--main-grid-gap);
          left: unset;
          height: unset;
          max-width: 36.5vw;
        }

        &.has-sidebar-page {
          #main-outlet-wrapper {
            grid-template-columns:
              var(--d-sidebar-width) calc(100vw - 38vw - var(--d-sidebar-width))
              1fr;
          }
        }

        &:not(.has-sidebar-page) {
          #main-outlet-wrapper {
            grid-template-columns: 0 calc(100vw - 52vw) 1fr;
          }

          #reply-control:not(.fullscreen).hide-preview {
            max-width: 46vw;
          }
        }

        .sidebar-wrapper .sidebar-container {
          height: unset;
        }
      }
    }
  }
}