mostly Indians uses brown varnish paints for their main wooden doors....I even don't know why they didn't use other colors...even in my house doors are given brown color wooden texture...

When dimensioning a classroom or teaching space, the best rule of thumb to produce both good sightlines and efficient layout is as follows: the space needs to be slightly rectangular, but NOT long and narrow. If X = 1, then Y should = 1.2 ideally, and no more than 1.5. Consider a comfortable space of 12 sqft. per student so if you have 6 students in a classroom then 72 sqft. + teaching space and walking space (60 sqft. or more) so say roughly you need 130 - 140 sqft. of space per class.

I've seen a lot of photos and I have come to realise that I really like the pastel/muted color pallete and have also come to know that they are good for small rooms. I really liked nickel grey and silver grey. Do both of these colors also belong to pastel color pallete? I am not able to find a separate section for pastel color pallete on asian paints' website. So it's difficult to find similar colors. Thanks for helping me.

Simple! Avoid paint! Simply buy 2 sheets of laminate (one for front and back each) that matches with the rest of your doors, and paste it on the PVC door using a strong adhesive (HeatX by Fevicol, or any other alternative). Enjoy! (Note: This solution can work only if there are no undulations on the peripheral frame of the door) I hope this was helpful.