
bootstrap-components
Guides proper usage of Bootstrap 4.5.2 components (navbar, cards, buttons, modals, forms). Use when
作者 yennanliu|オープンソース
Bootstrap Component Usage
Navbar Configuration
- Use Bootstrap navbar for responsive navigation
- Mobile hamburger menu with collapse
- Sticky or fixed positioning for persistent navigation
- Dark/light variants for theming
Example structure:
<nav class="navbar navbar-expand-lg navbar-dark bg-dark fixed-top">
<a class="navbar-brand" href="#">Brand</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarNav">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarNav">
<ul class="navbar-nav ml-auto">
<li class="nav-item"><a class="nav-link" href="#">Home</a></li>
</ul>
</div>
</nav>
Card Components
- Bootstrap card for uniform layouts
- Combines well with grid for responsive galleries
- Use card-deck for equal-height cards
- Custom footer for CTA buttons
Example:
<div class="card">
<img class="card-img-top" src="image.jpg" alt="Card image">
<div class="card-body">
<h5 class="card-title">Card Title</h5>
<p class="card-text">Description text</p>
<a href="#" class="btn btn-primary">Learn More</a>
</div>
</div>
Button Styling
- Use Bootstrap button classes: btn, btn-primary, btn-secondary
- Size variants: btn-sm, btn-lg
- State management: active, disabled, loading states
- Custom hover colors with CSS variables
Form Components
- Use Bootstrap form groups
- Validation states (is-valid, is-invalid)
- Floating labels for modern UI
- Accessible input types and labels
Example:
<form>
<div class="form-group">
<label for="email">Email address</label>
<input type="email" class="form-control" id="email" placeholder="name@example.com">
</div>
<button type="submit" class="btn btn-primary">Submit</button>
</form>
Grid System
- 12-column Bootstrap grid
- Responsive classes: col-xs, col-sm, col-md, col-lg, col-xl
- Utilities: gutter spacing, alignment
- Nesting for complex layouts
Example:
<div class="container">
<div class="row">
<div class="col-md-6 col-lg-4">Column 1</div>
<div class="col-md-6 col-lg-4">Column 2</div>
<div class="col-md-12 col-lg-4">Column 3</div>
</div>
</div>
Modal Components
- Use Bootstrap modals for overlays
- Fade animation for smooth transitions
- Centered or scrollable variants
- Proper accessibility (aria-labelledby, aria-hidden)
Custom Bootstrap Overrides
- Override Bootstrap variables before importing
- Use CSS variables for runtime theming
- Add custom classes alongside Bootstrap classes
- Avoid !important - use more specific selectors instead