ShadeTabSystem

ShadeTabSystem is a modular UI toolkit for tabbed navigation that uses perceptual shading to communicate focus, depth, and grouping. It provides a consistent shading model for tabs across themes, enabling applications to maintain readability and visual balance in light and dark environments.

The system centers on a shadeLevel attribute for each tab, ranging from 0 (unshaded) to 1 (strongly shaded). A theme engine maps shade levels to colors, borders, and text contrast, automatically adapting to dark mode, high-contrast mode, and user accessibility preferences. Transitions between shade states are designed to be smooth.

Architecture consists of a core data model (Tab, TabGroup, ShadePlan), a renderer layer for React, Vue, Svelte, or vanilla DOM, and a plugin-friendly API for custom tab behaviors. It uses a token-based theme system with CSS variables and supports virtualization for large tab sets to maintain performance.

Usage scenarios include web apps with complex tab bars, integrated development environments, browsers, and productivity tools. Developers can create or customize tabs, assign shade levels in response to activity, and handle events like activation, closing, or pinning. Accessibility considerations include contrast guarantees and keyboard navigation support.

ShadeTabSystem originated with Shade Labs and was released publicly in 2021 under an open-source license (MIT). Ongoing development focuses on interoperability, documentation, and community contributions.