CRT Scanlines CRT 扫描线
Horizontal lines every 4px, plus a full-canvas green wash that pulses in brightness. 每 4px 一条横线，再盖一层亮度会脉动的绿色。
Runs live on this page. Move the pointer, click, or drag — whichever the effect listens for. 就在本页实时运行。移动鼠标、点击或拖拽——看它响应哪一种。
How it works原理拆解
The scanlines are strokes at y += 4 with 15% opacity green. The flicker is a separate fillRect whose alpha is 0.04 + abs(sin(f))*0.05 — tying it to a sine of an accumulating counter rather than to time keeps the rhythm stable even if the frame rate varies. 扫描线是以 y += 4 步进、15% 透明度的绿色描边。闪烁是另一层 fillRect，透明度为 0.04 + abs(sin(f))*0.05——用的是累积计数器的正弦而不是时间，帧率波动时节奏也稳。
What to change可以改的地方
- 1Change the line spacing to 3px for a sharper, more modern display.
- 2Add slight horizontal offset per row to simulate signal noise.
- 1行距改成 3px，屏幕会更锐、更现代。
- 2每一行加一点横向偏移，就是信号噪声。
Source code源码
Self-contained — paste it into any HTML file and it runs. No libraries. 完全独立——粘进任意 HTML 文件就能跑，不需要任何库。