pgfdeclareverticalshading{beamer@barshade}{thepaperwidth}{%
   color(0ex)=(blue);%
   color(1ex)=(blue);%
   color(2ex)=(section in head/foot.bg);%
   color(7ex)=(section in head/foot.bg)%
}
pgfdeclareverticalshading{beamer@aboveframetitle}{thepaperwidth}{%
   color(0ex)=(blue);%
 color(1ex)=(blue);%
   color(2.5ex)=(section in head/foot.bg)
 }
pgfdeclareverticalshading{beamer@belowframetitle}{thepaperwidth}{%
  color(0ex)=(global.bg);%
  color(1ex)=(frametitle.bg)
}

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