@phoenix-plugin-registry/swmitra.html-designer/controlhtml/horizontalGripper.html

NOW WITH RESPONSIVE DESIGN TOOLS (BETA)! Design and customize web ui with HTML and CSS. Now with taggable Design snippet/bookmark support.

<div class="topcoat-button gripper" style="width:60px;height: 9px;top: -4px;box-sizing: border-box;position:absolute;left:calc(50% - 30px);padding: 0px;opacity: 0.9;cursor: ns-resize;border-radius: 0px;pointer-events:all;">
</div>