fix: custom ratio card alignment and dimensions layout

[shrutisharma-sh]

Fixes #1042

Changes

• Added col-span-1 and items-start to preset grid to fix Custom card misalignment
• Redesigned custom dimensions block into a 2-row layout:
  • Row 1: Width × Height inputs (flex, no overflow)
  • Row 2: Ratio pill badge (always visible, never clips outside container)

Root Cause

The Custom card was breaking grid rhythm on the last row, and the Ratio field was overflowing the sidebar panel (~27px outside bounds) because a single-row flex layout couldn't fit 3 columns in a ~273px wide container.

[vercel]

@shrutisharma-sh is attempting to deploy a commit to the magic-peach1's projects Team on Vercel.

A member of the Team first needs to authorize it.

[github-actions]

✅ PR Format Check Passed — @shrutisharma-sh

Basic format checks passed. A maintainer will review your code changes.

This does not mean the PR is approved — it just means the format is correct.

[github-actions]

👋 Thanks for your PR, @shrutisharma-sh!

Welcome to Reframe — a browser-based video editor built for everyone 🎬

What happens next

1. 🤖 Automated checks — build & TypeScript typecheck will run automatically
2. ✅ Vercel preview — a preview deployment will be created (requires maintainer authorization for fork PRs)
3. 👀 Code review — a maintainer will review your changes
4. 🚀 Merge — once approved, your PR will be merged!

Quick checklist

• PR title follows Conventional Commits (e.g. feat: add dark mode)
• Linked the issue this PR closes (e.g. Closes #123)
• Tested the changes locally (bun run dev)
• Build passes (bun run build)

Useful links

• 📖 CONTRIBUTING.md
• 🐛 Open Issues
• ⭐ Star the repo to support the project!

Happy coding! 🎉