30 year old needs advice on clothes shopping online?

I just turned 30, I’m a full time mom, wife and bank manager. I am afraid of falling in to an old lady fashion slump. I work with younger girls that always look amazing in their clothes but they shop at places like Forever 21 and Discovery. I feel I am too old to shop there aside from not having time to go to the mall. I have a very busy schedule and I was looking for good online stores where I can shop from home. I, of course still want to look professional at work but a little sexy and nice outside of work. Anyone have any good websites I can check out?

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