Dark Theme for Google Classroom - Supports both student and teacher views! Although this is mainly a dark theme, there are a couple of minor layout improvements here and there as well.
The theme is available through userstyles.world via the Stylus Extension, and through userstyles.net via the Stylish Extension.
v.1.5.7 Fix minor bugs introduced by Google Improve rich text control consistency
v.1.5.6 Improve the look of items and sections in the classwork page
v.1.5.5 Fix critical bugs introduced by Google
v.1.5.3 Very minor improvements
v.1.5.2 Improve text color declaration
v.1.5.1 Improve links, rubrics, text input labels, and picker dialogs
v.1.5.0 Improve visual coherence across pages and elements
v.1.4.13 Minor improvements
v.1.4.12 Style join class card from link Fix loading bar Add slight border to most card items
v.1.4.11 - Back to School Fall 2024 Fix a few changes made by Google
v.1.4.10 - Fix some big changes made by Google Improve the consistency of certain colors and effects across the platform Known Issue: Teacher view is still slightly affected by Google's changes in some minor areas. This will be addressed soon in the next update.
v.1.4.9 - Fix a couple of minor details that broke due to changes made by Google Lighten up some of the borders for a more clean design
v.1.4.8 - Bug fixes
v.1.4.7 - Fix a couple of minor details that broke due to changes made by Google
v.1.4.6 - Miscellaneous improvements for both student and teacher views
v.1.4.5 - Improve behavior of assignments on classwork page Improve behavior of link cards within assignments
v.1.4.4 - Unify sidebar elements on hover and focus Minor fix for hover color of non-clickable section titles
v.1.4.3 - Improve the work section of the student assignment page Improve the 'announce something to your class' area
v.1.4.2 - Improve the to-do page
v.1.4.1 - Improve the upcoming assignments panel within classes Improve schemes of several border and text colors throughout the interface
v.1.4.0 - Darken the assignment review page Fix a few minor details to keep up with changes from Google
v.1.3.2 - Improve visibility of several elements on hover
v.1.3.1 - Fix text color within apps popout
v.1.3.0 - Add support for the new sidebar design, as well as a few tweaks to keep everything looking great.
v.1.2.4 - Fix position and color of context menus on class list page
v.1.2.3 - Fix white background behind dragged class on class list page
v.1.2.2 - Fix color scheme of 'your work' page
v.1.2.1 - Add support for Google Apps menu Add support for YouTube video popup
v.1.2.0 - The Teacher Update Fixes many bugs, big and small, on the teacher side of the platform, as well as a couple student-side tweaks. With this update, there are now almost no broken or unsupported areas of the site. If you encounter an issue, please report it on GitHub so it can be resolved. Known Issue: Some context menus do not appear where expected. Workaround: Use each context menu in its new location.
v.1.1.3 - Fix color of Google Apps icon Improve consistency of to-do list items
v.1.1.2 - Fixed teacher appreciation week banner. This change would theoretically affect any future banners that Google puts up.
v.1.1.1 - Updated the internal ids of the drop-down setting to be clearer. This means that if you previously selected the "Follow System Theme" mode, you will need to re-select it before updating the style. Darkened the loading bar at the top - thanks Eduardo Werner!
v.1.1.0 - Assignments in the classroom page look better on hover and focus By default, the page is now dark no matter what, but there is a new option to have the page follow the browser-wide theme setting. Previously it would always follow the browser. Minor improvements
v.1.0.5 - Classes with the black color are displayed as white so they don't blend into the background Assignments in "your work" look better on hover and focus
v.1.0.4 - Minor upkeep due to a few changes on Google's end
v.1.0.3 - Small bug fixes
v.1.0.2 - Removed the white border around posts in the stream on hover. (Update: only for classes with the blue accent color... this is being fixed)
v.1.0.1 - A couple of minor bug fixes.
v.1.0.0 - I created this by myself. There are still a few bugs with the teacher view, but it is nearly perfect for students.