Baroque and Rococo seems to be similar styles but it isn't.
Baroque started with Trento Council,at the end of 16th Century, and ends with the death of Louis XIV,in 1715 .Rococo started with the regency of Philippe D'Orleans and ends with the French Revolution.

Baroque's dark,doctrinal,full of contrasts of colors,for example,black and gold or red and gold,with a coscience of the ephemeral and a bit of sadness.

17th century, architecture, and art image
Loreta,Prague
architecture image
Margravial Opera House in Bayreuth, Germany
17th century, altar, and architecture image
The tomb and altar of St. Ignatius Loyola in the Chiesa del Gesù (Church of the Jesuits) in Rome by Andrea Pozzo, 1695-99
17th century, art, and baroque image
Portait of Caterina Insarda, Marquise of Caluso and Delibera Eleonora S. Martino, 1658-63
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A Monk’s Burial by Alessandro Magnasco (1667–1749)
architecture, church, and art image
Church of the Gesù Ambulatory, Palermo

During Baroque Age it was very fashioned allegories about the life or politics.
Here some examples:

17th century, beautiful, and dark image
Ecclesia Surrounded by Symbols of Vanity by Jan Van Kessel The Elder
17th century, beautiful, and french baroque image
Simon Vouet. Prudence Leading Peace and Abundance. ca.1645
Mature image
Humana Fragilitas, Salvator Rosa,1656 This's a good example of vanitas\memento mori painting.
17th century, allegory, and art image
Gerard de Lairesse. Allegory of the Five Senses. 1668.
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Francesco Solimena, Allegory of Reign,1690

It were repeated in Rococo.But during Rococo were about love.

Rococo is joyful,with pastel colors,full of pleasure atmosphere and happiness and more relaxed,but both have the same target:
amaze the viewers.

18th century, architecture, and art image
St. Gallen, Switzerland
18th century, architecture, and art image
Oranienbaum, Chinese Palace(1762-1768)
18th century, art, and pale image
Esterhazy Palace, Fertöd, Hungary
18th century, art, and painting image
F.Boucher,“Allegory of Painting”, 1765
18th century, art, and beautiful image
Love Letter,Hubert Robert