Gothic architecture took off in the mid-1100s with cathedral builders opting for more artistic building styles as opposed to the most functional designs from before. The reason for the restrictions was that the weight could not be supported to allow for more creative expression.
The hallmark of Gothic architecture is the use of rib vault and flying buttresses which allowed the weight of the roof to be counterbalanced allowing for higher steeples and space for large windows. Bigger windows meant the opportunity to use the windows as another creative outlet which saw stained glass and rose windows is commonly used to bring beautiful colours to the inside of the cathedrals.
The first notable example is the Abbey of Saint-Denis close to Paris. Many master builders made pilgrimages to Saint-Denis to learn about the Gothic style and incorporate it into the cathedrals they would build in their cities and towns.