[hacker_9]

For my site [0] I found downloading a modern HTML5 template, and tweaking it as needed from user feedback, helped me learn a lot. Just using the dev tools and toggling CSS styles on and off helps a lot for intuitive understanding.

Also learning techniques when you need them helps with retaining knowledge. For example on desktop the features list alternates the image on the left and right per row, but for mobile when everything becomes one column I wanted the image to always be underneath the text. A few google searches later led me to the flex box which can easily reorder the cells by just changing the 'order' property. That's now a piece of modern CSS I can recall again for later use.

[0] http://www.waveform3d.com