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Only one item at a time can be selected from each level.
2nd level navigation should only be shown where relevant. Otherwise, the area beneath the line will remain empty.
Where there are 2 levels of navigation, only 2nd level items will load pages within the application. 1st level items only allow access to 2nd level items.
Menu items should be shown in a logical order, with the most commonly used first.
Menu item widths may be greater where there are fewer than 7 items in a level. The width of each item should be responsive to the item label, with the following limits:
1st level item labels: up to 30 characters (across 2 lines).
2nd level item labels: up to 16 characters (1 line only).
Truncation should be avoided, where possible, by using short labels.
No horizontal scroll can be used within top navigation.
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The header bar should expand/collapse with a transition effect.
Best Practices
General
Truncation should be avoided, where possible, by using short labels.
Number of items for both 1st and 2nd levels should not exceed 8 items.
Accessibility Compliance
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