How deep is the seat? M&S don't provide the info on their site and there are none to see in the local store. This one [[https://www.marksandspencer.com/wyatt-armchair/p/fhp60585157?Cushions=03750636&Fabrics=04895619&Legs=03882924#intid=pid_pg1pip9g4r2c1 https://www.marksandspencer.com/wyatt-armchair/p/fhp60585157?Cushions=03750636&Legs=03882924&Fabrics=04895619#intid=pid_pg1pip9g4r2c1]] Thanks