flex-splitter.min.css

[data-flex-splitter-horizontal],[data-flex-splitter-vertical]{display:flex;height:100%}[data-flex-splitter-horizontal]>*,[data-flex-splitter-vertical]>*{flex:none;overflow:auto;box-sizing:border-box}[data-flex-splitter-horizontal]>[role=separator],[data-flex-splitter-vertical]>[role=separator]{touch-action:none;display:flex;align-items:center;justify-content:center;overflow:visible;background-color:rgba(160,160,160,.15);z-index:100}[data-flex-splitter-horizontal]>[role=separator]:hover,[data-flex-splitter-vertical]>[role=separator]:hover{background-color:rgba(160,160,160,.45)}[data-flex-splitter-horizontal]>[role=separator]::before,[data-flex-splitter-vertical]>[role=separator]::before{content:"";box-sizing:border-box;border:4px rgba(160,160,160,.8)}[data-flex-splitter-horizontal]>[role=separator]{cursor:ew-resize;width:4px}[data-flex-splitter-horizontal]>[role=separator]::before{width:8px;margin:-2px;height:24px;border-style:double}[data-flex-splitter-vertical]{flex-direction:column}[data-flex-splitter-vertical]>[role=separator]{cursor:ns-resize;height:4px}[data-flex-splitter-vertical]>[role=separator]::before{width:24px;height:8px;margin:-2px;border-style:double}