Linking to a post in the forum about specifying CSS in a div inside markdown for alignment.
I was rambling about injecting custom CSS and specifying a list of new CSS classes in an arg of st methods (if I can edit the markdown/write, what if I want to change the styling of the sidebar with st.sidebar.slider(...csslist=[".red", ".hide"]), or maybe expose a specific custom class per component (like .st-sidebar) to change in an external file.
I stumbled on @isaac’s hack, which I like a lot and will reuse 
really a huge thanks for all those shared snippets !
Now I’m going to look for a way to change that sidebar color 
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