1st: Cyan color: Limited offer gold gacha, currently the wiki doesn't have a list of exactly what can be obtained from it (It hasn't updated since the last limited gold gacha yet), but we know it at least has the 3 current event girls shown (and probably more R/SRs to make it more difficult to obtain them).
2nd: Dark Blue color: Limited offer item gold gacha, the wiki has the list of what can be dropped from it here:
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I believe the only items in that list that drop from it currently are the "Resort Gacha items" at the bottom of each equipment type list there (Trident sea-god (water), Levi Ava Darling (water), etc).
3rd: Beige color: Limited offer silver gacha. It can drop event R's and rarer items than the normal one it seems, you can find the list of drops here:
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under "Limited Gacha"
4th: Purple color: Normal card gold gacha. The list of drops is here:
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5th: Light Blue color: Normal item gold gacha: You can find the list of what it drops here:
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under "Gacha Items".
6th: Grey color: Normal silver gacha: You can find the list of what it drops here:
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