right:4000pxright:autoright:0The red box which is hidden outside the viewport (to the left) has this style right:4000px.
"In the absolute positioning model, a box is explicitly offset with respect to its containing block."
"Absolute: The box's position (and possibly size) is specified with the 'top', 'right', 'bottom', and 'left' properties. These properties specify offsets with respect to the box's containing block."
"Each box is given a position with respect to its containing block, but it is not confined by this containing block; it may overflow."
"The containing block in which the root element lives is a rectangle called the initial containing block. For continuous media, it has the dimensions of the viewport and is anchored at the canvas origin; it is the page area for paged media. The 'direction' property of the initial containing block is the same as for the root element"
"This property specifies whether content of a block-level element is clipped when it overflows the element's box. It affects the clipping of all of the element's content except any descendant elements (and their respective content and descendants) whose containing block is the viewport or an ancestor of the element."
"Even if 'overflow' is set to 'visible', content may be clipped to a UA's document window by the native operating environment."
"This property specifies the base writing direction of blocks and the direction of embeddings and overrides (see 'unicode-bidi') for the Unicode bidirectional algorithm. In addition, it specifies the direction of table column layout, the direction of horizontal overflow, and the position of an incomplete last line in a block in case of 'text-align: justify'."
"This property specifies the base writing direction of blocks and the direction of embeddings and overrides (see 'unicode-bidi') for the Unicode bidirectional algorithm. In addition, it specifies the direction of table column layout, the direction of horizontal overflow, and the position of an incomplete last line in a block in case of 'text-align: justify'."