HTML CSS Tester

The HTML CSS Tester accepts HTML and CSS snippets as inputs and runs syntax, structure, and basic semantic checks. It identifies errors, warnings, and potential accessibility issues, then returns structured results suitable for automation. Conceptually, it parses the code into internal representations, validates against HTML5 and CSS3 rules, and flags invalid constructs with suggested fixes. The tool benefits developers issuing code reviews, QA engineers validating submissions, and students learning markup and styling by providing concrete remediation steps. Core value lies in fast feedback loops, standardized checks, and exportable results that integrate into CI pipelines or learning workflows. Use cases include validating new components, ensuring accessible markup, and verifying CSS rules across common browser engines. Unique differentiators are its multi-input design, structured error reporting with locations when available, and the ability to export results for further processing. Core features include HTML5 validation, CSS syntax checks, basic accessibility cues, cross-browser notes, and machine-readable outputs for integration. Optional features cover lint-style rules, CSS specificity hints, and batch analyses. The tool focuses on syntax correctness, semantic plausibility, and accessibility cues rather than rendering or performance profiling.