@hariram159 The solution is based on panel not viz. If you notice closely it is based on Panel IDs.
Also if you have some hurdles with Splunk Admin uploading the CSS file, the Simple XML CSS extension can remain within Dashboard code as provided in the example. However, if you would want to make CSS re-usable you will have to consider Pre-Built Panel or else moving to a CSS Stylesheet in the appserver/static folder.
What difference do you want to achieve with Pixel and not %? Is the width of Browser/Display always fixed for you and you want the three panels to consume specific width no matter what is the total width of the browser/display? In either, case you can change from percent to Pixels (px) and it should still work the way CSS style overrides are supposed to.
If you are new to Simple XML CSS extension in Splunk or CSS itself read the following excellent Clara-fication blog by @cmerriman https://www.splunk.com/en_us/blog/tips-and-tricks/splunk-clara-fication-customizing-simplexml-dashbo...
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