danielnichols on "[Plugin: Contact Form 7] Telephone input"

I have a telephone input on my site ...

http://test.nichols.org.uk/booking/make-a-booking/

For some reason this is shorter than the others on a pc monitor and sticks out far too long on a mobile device.

Any help is much appreciated! Thanks!

http://wordpress.org/extend/plugins/contact-form-7/