https://www.ted.com/talks/neil_harbisson_i_listen_to_color
http://www.colorsontheweb.com/Color-Theory/Color-Contrast
https://color.adobe.com/create/color-wheel/
http://flatuicolors.com
https://www.webdesignrankings.com/resources/lolcolors/
https://uigradients.com/#ColorsOfSky
http://htmlcolorcodes.com
https://www.hexcolortool.com
https://www.canva.com/learn/color-meanings-symbolism/
https://www.huffingtonpost.com/smartertravel/what-colors-mean-in-other_b_9078674.html
https://webaim.org/resources/contrastchecker/