[Glitch] Add language dropdown to compose in web UI

Port 0cdb077570 to glitch-soc

Signed-off-by: Claire <claire.github-309c@sitedethib.com>

app/javascript/flavours/glitch/styles/components/composer.scss

@@ -644,3 +644,68 @@
     & > .count { color: $warning-red }
   }
 }
+
+.language-dropdown {
+  &__dropdown {
+    position: absolute;
+    background: $simple-background-color;
+    box-shadow: 2px 4px 15px rgba($base-shadow-color, 0.4);
+    border-radius: 4px;
+    overflow: hidden;
+    z-index: 2;
+
+    &.top {
+      transform-origin: 50% 100%;
+    }
+
+    &.bottom {
+      transform-origin: 50% 0;
+    }
+
+    .emoji-mart-search {
+      padding-right: 10px;
+    }
+
+    .emoji-mart-search-icon {
+      right: 10px + 5px;
+    }
+
+    .emoji-mart-scroll {
+      padding: 0 10px 10px;
+    }
+
+    &__results {
+      &__item {
+        cursor: pointer;
+        color: $inverted-text-color;
+        font-weight: 500;
+        padding: 10px;
+        border-radius: 4px;
+
+        &:focus,
+        &:active,
+        &:hover {
+          background: $ui-secondary-color;
+        }
+
+        &__common-name {
+          color: $darker-text-color;
+        }
+
+        &.active {
+          background: $ui-highlight-color;
+          color: $primary-text-color;
+          outline: 0;
+
+          .language-dropdown__dropdown__results__item__common-name {
+            color: $secondary-text-color;
+          }
+
+          &:hover {
+            background: lighten($ui-highlight-color, 4%);
+          }
+        }
+      }
+    }
+  }
+}