Chico UI is an open source free jquery user interface web tools to ease developing for developers and designers.
Built on top of jQuery these tools brings known interaction patterns for your website taking advantage of HTML5 and CSS3 features.
The components include auto-complete, blink, calendar, carousel, countdown, date-picker, dropdown, expando, form, top navigation, validation, zoom and more.
There is a CSS layout framework named Chico Mesh for accomplishing any type of web layouts and grids.
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Also, a CSS library exists for styling HTML and UI elements like lists, tables, buttons, typography, pagination.etc..
Each Chico UI resource is well-documented + supported with demos and various tutorials exist for more details.