Improve documentation and try furo

[gaborbernat]

Resolves #1881

[codecov]

Codecov Report

Merging #2180 (59e2ed8) into rewrite (bb6ff6b) will not change coverage.
The diff coverage is n/a.

❗ Current head 59e2ed8 differs from pull request most recent head 1a3b26b. Consider uploading reports for the commit 1a3b26b to get more accurate results

@@           Coverage Diff            @@
##           rewrite    #2180   +/-   ##
========================================
  Coverage    99.85%   99.85%           
========================================
  Files          157      157           
  Lines         8944     8944           
  Branches       939      939           
========================================
  Hits          8931     8931           
  Misses           3        3           
  Partials        10       10           

Flag	Coverage Δ
tests	99.85% <ø> (ø)

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