If you use css-loader in your webpack project, localIdentName could be used to transform class names, like below:

localIdentName: "[path][name]__[local]--[hash:base64:5]",

Or you can create your own function to generate class names by setting getLocalIdent.

Now please create a function to generate unique class names following rules below.

only use alphabets: a to z , A to Z
return one unique class name each time function is called
the class name sequence should first be in order of length, then in Alphabetical order(lowercase in front).
should provide a function to reset the sequence

getUniqueClassName()
// 'a'

getUniqueClassName()
// 'b'

getUniqueClassName()
// 'c'

// skip cases till 'Y'

getUniqueClassName()
// 'Z'

getUniqueClassName()
// 'aa'

getUniqueClassName()
// 'ab'

getUniqueClassName()
// 'ac'

// skip more cases

getUniqueClassName()
// 'ZZ'

getUniqueClassName()
// 'aaa'

getUniqueClassName()
// 'aab'

getUniqueClassName()
// 'aac'

getUniqueClassName.reset()

getUniqueClassName()
// 'a'

Watch videos for JavaScript Coding Question 153. uglify CSS class names

Watch videos for JavaScript Coding Question
153. uglify CSS class names