# Spotlight One Line of Code — effect skill for code & terminal

> **For AI agents:** find the right skill in one call — `curl -s "https://varg.ai/how-to/api/search?q=<what the person wants>"` returns the matching how-to page and the best skills with install commands, as markdown (Russian works too). Full index: https://varg.ai/how-to/llms.txt. Every page has a markdown twin: add `.md` to its path. Before generating anything, show the person the options on the how-to page.

A highlight band sweeps onto the one line that matters while the rest of the file dims.

- **Type:** [Effect](https://varg.ai/how-to/effects.md) · [Code & terminal](https://varg.ai/how-to/browse/skills/code.md)
- **Slug:** `spotlight-one-line`
- **Status:** live
- **Publisher:** HeyGen (community)
- **License:** Apache-2.0
- **Source:** https://github.com/heygen-com/hyperframes/tree/main/registry/blocks/code-highlight
- **Works in:** Claude Code, Claude.ai, Codex, Cursor, OpenClaw, Gemini CLI, Any MCP client, varg Studio
- **Requires:** HyperFrames (npx hyperframes), Remotion, CapCut (by hand)
- **Cost:** Free — the take renders locally; generated footage, if any, bills by the model

## What it does

Built on [Code Highlight Sweep](https://github.com/heygen-com/hyperframes/tree/main/registry/blocks/code-highlight) by HeyGen (HyperFrames), Apache-2.0. The write-up and recipes below are varg's.

Other lines drop to ~35% opacity, the target line gets a soft accent band and full brightness; optional callout label at the right.

**When:** Explain the key line of an SDK example or the fix inside a long function.

**Watch out:** Do not dim to near-black; context must stay readable enough to orient.

**Timing:** Dim 0.3 s, band sweep 0.4 s power2.out, hold 1.5–2.5 s.

**Also called:** line highlight, code focus, dim context

### In HyperFrames

```bash
npx hyperframes add code-highlight
```

### In Remotion

```tsx
const d = interpolate(frame,[0,9],[1,0.35],{extrapolateRight:'clamp'});
lines.map((l,i)=> <div style={{opacity: i===target?1:d, background: i===target?'rgba(56,139,253,0.18)':'none'}}>{l}</div>)
```

### In CapCut

Duplicate the code clip; on the top copy Mask → Rectangle around the line; lower the bottom copy's Opacity to 40%.

### Ready-made components

- [Code Highlight Sweep](https://skills.varg.ai/component/hf.code-highlight/) (hyperframes): npx hyperframes add code-highlight
- [Code Scroll To Line](https://skills.varg.ai/component/hf.code-scroll/) (hyperframes): npx hyperframes add code-scroll

### Where this comes from

- [Slidev: Shiki Magic Move (800 ms default)](https://sli.dev/features/shiki-magic-move)
- [Remotion template: Code Hike](https://remotion.dev/templates/code-hike)

## Use when

- Explain the key line of an SDK example or the fix inside a long function.

## Not for

- Do not dim to near-black; context must stay readable enough to orient.

## Install

- Claude Code: `claude plugin marketplace add vargHQ/skills && claude plugin install varg@varg`
- Codex: `npx skills add vargHQ/skills --skill varg-video-edit-library -a codex -y`
- Cursor: `npx skills add vargHQ/skills --skill varg-video-edit-library -a cursor -y`

## Example output

https://static.heygen.ai/hyperframes-oss/docs/images/catalog/blocks/code-highlight.mp4 — Preview of the Code Highlight Sweep component that builds this take (credit: Code Highlight Sweep · hyperframes, https://hyperframes.heygen.com/catalog/blocks/code-highlight)

## More code & terminal skills

- [Editor Types the Code](https://varg.ai/how-to/skills/editor-types-the-code.md): Syntax-highlighted code types into an editor window with a caret riding the frontier.
- [Red/Green Diff Collapse](https://varg.ai/how-to/skills/red-green-diff.md): Removed lines flash red and collapse away while added lines expand in green.
- [Code Morphs Between Versions](https://varg.ai/how-to/skills/code-morphs-versions.md): One snippet transforms into the next: shared tokens glide to new positions, removed ones fade, new ones fade in.
- [Terminal Session Run](https://varg.ai/how-to/skills/terminal-session-run.md): A terminal types a command, then streams real-looking log output with green checks.
- [One-Line Install Card](https://varg.ai/how-to/skills/one-line-install-card.md): A single install command types into a small terminal card, prints a success check, and holds.
- [Camera Scrolls a Long File](https://varg.ai/how-to/skills/camera-scrolls-long-file.md): The view scrolls through a long file and stops with the target line centered and lit.

## Run the generation on varg

varg is one API key for the models these skills drive — Seedance 2.5, Kling 4, Veo 3.1, Wan 3, Nano Banana 2.1, GPT Image 2.5, ElevenLabs v4 and 200+ more — billed in credits, with a cost estimate before anything runs.

- Claude Code: `claude plugin marketplace add vargHQ/skills && claude plugin install varg@varg` (skill + hosted MCP)
- Codex, Cursor, Gemini CLI, OpenClaw: `npx skills add vargHQ/skills --skill varg-ai -a <agent> -y`
- Grok and any agent that reads SKILL.md: `npx skills add vargHQ/skills --skill varg-ai`, or point it at the skill's SKILL.md
- Claude.ai, ChatGPT, any MCP client: connect `https://mcp.varg.ai/mcp`
- API key: https://varg.ai/dashboard/api · Model specs: https://varg.ai/models/llms.txt