Here are some common CSS mistakes we all make

[balajiseo]

Not Using a Proper CSS Reset. Web browsers are our fickle friends.
Over-Qualifying Selectors.
Not Using Shorthand Properties.
Using 0px instead of 0.
Using Color Names Instead of Hexadecimal.
Redundant Selectors.
Redundant Properties.
Not Providing Fallback Fonts.

[Vishri]

When I was working on a UI for a white-label budgeting software project https://kindgeek.com/white_label_pfm_platform, these small CSS missteps started stacking up. Suddenly, what looked fine in Chrome broke in Firefox. That's when I learned the value of using a proper CSS reset and keeping code clean and efficient. It's funny how small habits, like using shorthand or hex codes instead of color names, can really improve consistency and performance. CSS can feel deceptively simple, but attention to detail makes all the difference in a polished product.

[Mastershivasaiji]

Overly specific selectors, fixed widths/heights, inline CSS, and repeated values make CSS fragile and hard to scale. Instead use simple class-based selectors, relative units, modular stylesheets, variables, and responsive design.