Header layout should behave like a fluid flex or grid container rather than a static row with reserved positions.

[JoaoLR64]

What type of request is this?

New dashboard feature

Existing card or feature name

None

Describe the enhancement

In Home Assistant dashboard headers where cards are arranged horizontally, cards are frequently shown or hidden based on entity state (e.g. conditions, modes, users, time).

When a card becomes hidden:

Its space is not properly reclaimed in a way that recenters the remaining visible cards
The header appears visually unbalanced (shifted or left-aligned)
The layout behaves like a fixed horizontal slot system rather than a fluid container

This creates a UX inconsistency that is especially noticeable in headers, where visual symmetry and balance are important.

**Expected Behavior

When header cards are dynamically hidden:**

Remaining visible cards should automatically reflow
The group of visible cards should remain centered within the header
No empty spacing or “ghost slots” should remain after a card is hidden
The layout should behave like a fluid flex/grid container rather than a static row with reserved positions

**💡 Suggested Improvement

The header layout system should properly support dynamic reflow on state changes by:**

Recomputing layout when card visibility changes
Ensuring hidden cards are fully removed from layout flow (not only visually hidden)
Using a flexible layout model (flexbox or grid) that supports automatic centering of remaining items

📊 **Impact

This improvement would significantly enhance:**

Visual balance of dynamic dashboards
Mobile and responsive header layouts
State-driven UI designs (very common in Home Assistant)
Overall polish and perceived quality of dashboard rendering
User experience consistency when dashboards are highly dynamic
🧠 Why this matters

Home Assistant dashboards are inherently state-driven. When header content changes dynamically, the layout should adapt visually in real time rather than preserving static alignment behavior.

Visual examples

No response

Anything else?

No response