Boil the raspberries, water and sugar for 5 minutes.
Pass them through a sieve and chill for at least 4 hours.
Add the lime just before drinking it so it doesn't go bitter.
Turn the glass over a dish with a bit of water so the rim gets wet.
Repeat over brown sugar and let it rest for 5min so it dries a bit.
Fill 1/4 of the glass with the syrup and then fill the rest with sparkling wine. Add a few raspberries so they float around.