I have been getting blonde foils for about a year now on the top half of my hair and as you can imagine it is pretty blonde, however at the same time I started dying the top blonde, I dyed the underneath of my hair a dark purple/brown colour. I have stopped doing this about 5 months ago and have about 10cms of regrowth underneath, but I want my whole hair to be blonde now. How can I achieve this without the underneath without it turning an ugly orangey colour? I have quite long hair, and I don't want to have to cut it if possible, any suggestion would be great :):)