Introduction to CSS Grid

CSS Grid Layout is a powerful 2-dimensional system that enables designers to create complex web layouts easily. It's native to CSS and has extensive browser support, revolutionizing the way we design grid-based user interfaces.

To initiate a grid layout, designate a container element with 'display: grid'. This creates a new grid formatting context for all its child elements, allowing you to define rows and columns with 'grid-template-rows' and 'grid-template-columns'.

The 'fr' unit in CSS Grid represents a fraction of the available space. It allows columns and rows to be sized relative to each other, ensuring fluid adaptability and efficient space distribution without the need for media queries.

Items in a grid can be positioned precisely using grid line numbers, names, or the 'span' keyword. This level of control is unique to Grid, surpassing older layout techniques in both simplicity and flexibility.

With 'grid-template-areas', you can create a template by assigning names to areas of your layout. This semantic approach simplifies layout changes and enhances readability while maintaining the overall structure.

Grid's auto-placement feature fills in empty cells with unassigned items, saving time and code. It adjusts automatically to new content and is customizable with 'grid-auto-flow', catering to different layout needs.

Subgrid extends the grid's capabilities into nested elements, allowing child grids to align directly with the main grid's columns and rows. This feature, introduced in CSS Grid Level 2, promotes design consistency across complex layouts.