Question

My client is asking me to reduce size of current website for desktop browsers by 30%.

is there a css or meta tag to do it like viewport meta tag on a mobile browser?

Answer 1

You can look at the css screen media type.

It is:

Intended primarily for color computer screens.

You can use it this way:

@media screen {
  body { font-size: 70% }
}

There is also a handheld media type, primarily:

Intended for handheld devices (typically small screen, limited bandwidth).

However, you will need to test the different devices and desktops your client is focusing on in order to determine how using these media types will effect the user experience.