I created a BMI calculator to watch my weight. This is simple Javascript skinned with BootstrapJS

Bootstrap is an open-source front-end framework for building responsive and visually appealing web applications. It provides a collection of pre-designed HTML, CSS, and JavaScript components, as well as a responsive grid system, that streamline the process of designing and developing consistent and modern user interfaces.

The primary goals of Bootstrap are to:

Ease of Use: Bootstrap simplifies web development by offering a set of ready-to-use components and styles. Developers can quickly build and prototype web interfaces without having to start from scratch.

Responsive Design: Bootstrap's responsive grid system allows developers to create layouts that adapt to different screen sizes and devices, ensuring a consistent user experience across desktops, tablets, and mobile devices.

Consistency: By using Bootstrap's design and components, developers can achieve a consistent and cohesive look and feel throughout their web application, regardless of the team's design skills.

Customizability: While Bootstrap provides a default theme, it's highly customizable. Developers can easily modify colors, typography, and other design elements to match their branding.

Cross-Browser Compatibility: Bootstrap is designed to work across different web browsers, helping ensure that your application looks and functions consistently for users.

Key features and components of Bootstrap include:

Responsive Grid System: Bootstrap's grid system allows developers to create flexible and responsive layouts by organizing content into rows and columns.

Typography: Bootstrap provides a set of typography styles for headings, paragraphs, lists, and other text elements.

CSS and Components: Bootstrap offers a wide range of CSS classes and components for buttons, forms, navigation bars, modals, alerts, cards, and more.

JavaScript Plugins: Bootstrap includes JavaScript plugins for interactive features like carousels, modals, dropdowns, tooltips, and more.

Customizable Themes: Developers can create custom themes by modifying variables and styles in the Bootstrap source code, or by using online tools that generate custom stylesheets.

Documentation and Community: Bootstrap has extensive documentation, examples, and a large community of developers who share tips, tricks, and solutions.