discourse/themes/horizon/scss/desktop-horizon-fixes.scss

.topic-list .topic-list-header .topic-list-data:last-of-type {
  padding: 0;
}

// Fixing bulk select (only needed for desktop)
.bulk-select-enabled {
  body:not(.user-messages-page) & {
    .topic-list-header {
      position: sticky;
      top: 8em;
      height: 0;
      z-index: 1;
    }

    .topic-author-avatar-data {
      display: none;
    }

    .bulk-select.topic-list-data {
      grid-area: bulk-select;
      margin-left: -0.5em;

      @media screen and (width <= 576px) {
        margin-top: 0;

        label {
          padding-block: 0.345em;
        }
      }

      input {
        transform: scale(1.5);
      }
    }
  }
}

.topic-list-header {
  body:not(.user-messages-page) & {
    tr {
      border: none;
    }

    .topic-list-data {
      padding: 0;

      &:not(.default) {
        display: none;
      }

      &.default {
        .bulk-select,
        span:not(.bulk-select-topics, .d-button-label) {
          display: none;
        }
      }

      .bulk-select-topics {
        position: absolute;
        right: var(--space-2);
        top: var(--space-2);
        background: transparent;
        border-radius: var(--d-border-radius);
        display: flex;
        gap: 0.5rem;
        margin: var(--space-4) 0;
        padding: var(--space-1);

        button {
          white-space: nowrap;
          margin: 0;
        }
      }
    }
  }
}