- Remove iframe height calculation logic
- Turn on iframe default scroll
- Increase sidebar heigth 99vh to 100vh

Reviewed-by: Suwon Chae

Reviewed-by: Suwon Chae

Reviewed-by: Hyunjae Park

Reviewed-by: Hyunjae Park

- Show scrolls at only the list area
- Increase scrollbar size in Chrome

IE browser has default font size for li element.
So sometimes it ruins the margin of li elements.

```
font-size: 0;
```

Above is needed to workaround this kind of problem.
I'm not sure of its mechanism exactly but it works.

Reviewed-by: Suwon Chae

Reviewed-by: Hyunjae Park

Reviewed-by: Suwon Chae

Reviewed-by: Suwon Chae

Reviewed-by: Suwon Chae

Reviewed-by: Hyunjae Park