CSSBattle vs Yandex Contest

CSSBattle is a web game for practicing HTML and CSS by rebuilding target images with the shortest possible code. Scores reflect both visual similarity and character count. You can open targets and write code without an account, but logging in is required to submit and receive a score. A new Daily Target appears at 00:00 UTC; these daily challenges have no leaderboards. Battles use separate targets and leaderboards, while private Versus battles support one-on-one challenges with friends. Submissions cannot use JavaScript, SVG, images, or external assets, and are rendered in a headless Chromium browser on Ubuntu 18.04. Learn courses add interactive levels and quizzes for beginners, intermediate learners, and experts. The free plan permits only the current day’s target. PLUS adds more than 1,100 past Daily Targets, top solutions, plugins, statistics, search and sharing, unlimited history, and a VSCode editor. CSSBattle Free costs nothing; PLUS costs $4.90 a month or $59 a year.

Yandex Contest is a free online platform for programming competitions, practice, and lessons with automatic solution checking. Organizers can create problems or select ready-made sets, then configure rules, deadlines, ratings, and invitations. Contests support individual or team participation and may be open or restricted. A testing server evaluates submissions according to contest rules. The platform lists more than 20 programming languages, with compiler settings for supported languages, and its demo includes checker-based, interactive, run-twice, test, text-answer, and matching problems. The public API uses OAuth permissions to register participants, manage groups, retrieve contest and problem details, submit or rejudge solutions, and export leaderboards. Users sign in with Yandex ID or organizer credentials. The organizer plan is free for up to 10,000 participants; organizers expecting more must contact Yandex. Full administrator-panel access requires a form.