What was the style and color of clothing like in the 1700-1800s?

Question

for girls around the age of 15-18

Answer 1

At that time a girl of 15 - 18 would be dressing as an adult. Her marital status would determine some aspects of her hair style and clothing.

What part of the world are you interested in?
These websites should give you the answers:
Native American dress
http://www.nativeartstrading.com/Welcome.html
American Colonial Women
http://www.history.org/history/clothing/women/index.cfm
17th century
http://www.reconstructinghistory.com/17thc/index.html
18th century
http://www.reconstructinghistory.com/18thc/index.html
The history of clothing in Africa
http://africastyles.com/blackhistory/history_clothing.html
Clothing of the 1830’s
http://www.connerprairie.org/HistoryOnline/clothing.html
Encarta Encyclopedia History of clothing
http://autocww.colorado.edu/~blackmon/E64ContentFiles/DecorativeArts/Clothing.html