fix: replace hardcoded max-width in .ease-container with CSS variable

[Pcmhacker-piro]

• Added --ease-container-max: 1200px to core/variables.css
• Updated .ease-container in core/utilities.css to use var(--ease-container-max)

Users can now override container width via
:root { --ease-container-max: 960px; }
without needing !important.

Closes #847

Pull Request Description

.ease-container had a hardcoded max-width: 1200px that could not be themed via CSS variables. This PR introduces --ease-container-max as a design token, making the container width fully customizable.

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Type of Change

• ✨ New animation / hover effect
• 🧩 New component
• 📝 Documentation improvement
• 🐛 Bug fix in an existing submission
• Other (describe below)

CSS variable theming fix for .ease-container.

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Submission Checklist

⚠️ PRs that fail this checklist will be closed without review.

• All changes are inside submissions/examples/your-feature-name/
• Includes demo.html — self-contained, opens in browser with no server
• Includes style.css — raw CSS for the proposed feature
• Includes README.md — what it does, how to use it, why it fits EaseMotion CSS
• No changes to core/
• No changes to components/
• One feature per PR (no bundled unrelated changes)

Note: This PR changes core/ (variables.css and utilities.css) because it fixes a core framework issue, not a user submission. The submission checklist above does not apply directly.

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Feature Description

What does this add?

CSS variable --ease-container-max (default 1200px) to make .ease-container width themable.

How does a developer use it?

/* Override in your own stylesheet */
:root {
  --ease-container-max: 960px;  /* blog layout */
}
Why does it fit EaseMotion CSS?
Every other token uses CSS variables — this makes .ease-container consistent with the framework's theming philosophy.
Demo
N/A — core framework fix, no new submission.
Browser Testing
- Chrome
- Firefox
- Edge
- Safari (optional but appreciated)
Notes for Maintainer
No behavior change by default — --ease-container-max defaults to 1200px, the original hardcoded value.

[Pcmhacker-piro]

heyy @SAPTARSHI-coder i fixed the your assigned issue so please check this

[Pcmhacker-piro]

heyy @SAPTARSHI-coder
i fixed the issue so pls check it

[Pcmhacker-piro]

heyy @SAPTARSHI-coder
i fixed the issue so pls check it