CSS Accordion Generator
Build responsive, animated pure CSS accordions using native HTML5 <details> and <summary> with zero JavaScript required.
🎨 Header & Icon Options
📐 Spacing & Dimensions
What is UtilVox?+
UtilVox is a high-performance utility suite offering instant CSS generators, developer tools, financial calculators, and unit converters engineered for precision.
How does the pure CSS accordion work?+
Pure CSS accordions use the native HTML5 <details> and <summary> elements styled with modern CSS transitions, requiring zero JavaScript to function.
Is it fully responsive and accessible?+
Yes, HTML5 details/summary tags are natively accessible via keyboard navigation (Space / Enter keys) and scale responsively across all screen sizes.
Can I export production-ready code?+
Every generated accordion snippet includes clean HTML markup and CSS stylesheet rules ready for immediate 1-click clipboard copying.
/* Pure CSS Accordion using <details> and <summary> */
.accordion {
width: 100%;
max-width: 650px;
border: 1px solid rgba(255, 255, 255, 0.1);
border-radius: 12px;
overflow: hidden;
}
.accordion details {
border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}
.accordion details:last-child {
border-bottom: none;
}
.accordion summary {
list-style: none;
padding: 16px 20px;
background: #14141a;
color: #e4e1e9;
cursor: pointer;
display: flex;
justify-content: space-between;
align-items: center;
font-weight: 700;
font-size: 15px;
user-select: none;
transition: background 0.3s ease, color 0.3s ease;
}
.accordion summary::-webkit-details-marker {
display: none;
}
.accordion summary::after {
content: '+';
font-size: 1.2em;
line-height: 1;
transition: transform 0.3s ease;
}
.accordion details[open] summary {
background: #1f1f25;
color: #f5c842;
}
.accordion details[open] summary::after {
transform: rotate(45deg);
}
.accordion .accordion-content {
padding: 16px 20px;
background: rgba(0, 0, 0, 0.2);
color: #a1a1aa;
font-size: 14px;
line-height: 1.6;
}
/* Fallback hiding */
.accordion details:not([open]) .accordion-content {
display: none;
}Mastering Pure CSS Accordions & Accessible Collapsible Panels
Pure CSS Height Transitions via CSS Grid
Historically, animating height to auto in pure CSS was difficult. Modern CSS solves this using grid-template-rows: 0fr to grid-template-rows: 1fr, enabling silky 60 FPS transitions without knowing content dimensions in advance.
| Behavior | HTML Implementation | Recommended Use |
|---|---|---|
| Single Item | Radio buttons (<input type='radio'>) | FAQ sections, product feature highlights |
| Multiple Items | Checkboxes (<input type='checkbox'>) | Filters, sidebar navigation drawers |
| Native Details | HTML5 <details> and <summary> | SEO documentation, lightweight content widgets |
Pairing with Other UtilVox Developer Tools
Combine accordions with our CSS toggle switch generator, build modals with our CSS modal generator, or customize responsive headers with our CSS navbar generator.