Hola hades87. Gracias por la respuesta.
Lo estuve mirando pero al empezar a darle más contenido a la columna del medio por ejemplo agregando mas texto llega un momento en que los limites inferiores de las columnas 1 y 3 quedan y el texto continua para abajo en una forma medio rara. justamente lo que necesito es que parezca que todo continua. y por otro lado no abarca toda la ventana en forma horizontal (el 100% de la ventana)
Si pones en la columna2 este contenido te darás cuenta
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