Το κίτρινο μου πάει περισσότερο το καλοκαίρι.

Because το κίτρινο here means the color yellow. In Greek, adjectives can be used as nouns when talking about colors, qualities, or abstract ideas.

So:

• κίτρινος = yellow (masculine adjective)
• κίτρινη = yellow (feminine adjective)
• κίτρινο = yellow (neuter adjective)

But:

• το κίτρινο = yellow as a color

This is similar to English using an adjective like a noun in Yellow suits me.

The article το is needed because Greek normally treats color names like this as nouns with an article.

So το κίτρινο is not just yellow as an adjective; it is the yellow color or simply yellow as a noun.

Greek often uses the article in places where English does not. So even if English says Yellow suits me, Greek naturally says Το κίτρινο μου πάει.

Μου πάει is a very common expression meaning:

• it suits me
• it looks good on me
• it is flattering on me

The verb is πάω / πηγαίνω, but in this expression it does not mean literal movement like go. It has the idiomatic meaning suit.

So:

• Μου πάει το μπλε. = Blue suits me.
• Δεν μου πάει αυτό το φόρεμα. = This dress doesn’t suit me.

Because the person affected is expressed with an indirect object in Greek.

• μου = to me / for me
• με = me (direct object)

With πάει in the sense of suits, Greek uses the indirect-object pronoun:

• Μου πάει = It suits me
• literally closer to It goes well to me

So even though English says me, Greek uses μου.

Περισσότερο means more.

In this sentence, it means something like:

• it suits me more
• it suits me better
• I suit yellow more in summer

The comparison is often left implicit in Greek, just as it can be in English. The sentence suggests:

• more than in other seasons
• more than at other times
• better in summer than otherwise

So περισσότερο is modifying the idea of μου πάει.

Yes, very often there is.

Greek does not always need to spell out what the comparison is. In this sentence, the listener usually understands something like:

• more than in winter
• more than during the rest of the year
• more than other colors do at that time

If you wanted to make the comparison explicit, you could add it:

• Το κίτρινο μου πάει περισσότερο το καλοκαίρι παρά τον χειμώνα.
  Yellow suits me more in summer than in winter.

Greek often uses the article with seasons, days, and time expressions.

So:

• το καλοκαίρι = in summer / during the summer

This is very natural Greek. English often drops the article, but Greek usually keeps it.

Other examples:

• τον χειμώνα = in winter
• την Κυριακή = on Sunday
• το πρωί = in the morning

So το καλοκαίρι is not unusual at all.

In this sentence, it means in summer / during the summer season in general.

Greek uses the article in general time expressions, so το καλοκαίρι does not automatically mean this summer.

If the context strongly pointed to a specific summer, it could be understood that way, but on its own here it is best understood as a general seasonal statement.

Greek word order is more flexible than English word order. The sentence:

Το κίτρινο μου πάει περισσότερο το καλοκαίρι.

is completely natural, but other orders are possible too, depending on emphasis.

For example:

• Μου πάει περισσότερο το κίτρινο το καλοκαίρι.
• Το καλοκαίρι μου πάει περισσότερο το κίτρινο.

These all mean roughly the same thing, but the focus shifts a little:

• Το κίτρινο first emphasizes the color
• το καλοκαίρι first emphasizes the season
• μου πάει περισσότερο in the middle keeps the sentence balanced and natural

So the given word order is normal, not random.

Yes. Πάει and πηγαίνει come from the same verb.

• πάει is the more common everyday form
• πηγαίνει is a fuller form and can sound a bit more formal or careful, depending on context

So:

• Το κίτρινο μου πάει περισσότερο το καλοκαίρι.
• Το κίτρινο μου πηγαίνει περισσότερο το καλοκαίρι.

Both are grammatically correct. In everyday speech, πάει is especially common.

Because Greek uses μου πάει as the natural way to express the idea it suits me / it looks good on me.

English may say:

• Yellow looks better on me in summer
• I wear yellow better in summer
• Yellow suits me more in summer

Greek does not need to match those English structures exactly. The idiomatic Greek way is simply:

• Το κίτρινο μου πάει...

So this is a case where you should learn the whole expression as a chunk.

Yes. Very often περισσότερο literally means more, but in natural English this sentence may come out as better.

That is because English often prefers better with verbs like suit or look good:

• literal-ish: Yellow suits me more in summer
• natural English: Yellow suits me better in summer

So grammatically Greek uses more, but idiomatic English may prefer better.

Not exactly. Περισσότερο means more, not most.

If you wanted most, you would normally use:

• Το κίτρινο μου πάει περισσότερο απ’ όλες τις εποχές το καλοκαίρι.
• or another clearer rewording depending on context

The original sentence is comparative, not superlative. It means that summer is the season when yellow suits you more, usually compared with other times.

It can cover all of those, depending on context.

Το κίτρινο can refer to:

• yellow clothes
• the color yellow on you
• yellow shades in what you wear

Greek leaves this fairly broad unless the speaker specifies more. So the sentence naturally allows the interpretation:

• yellow clothing suits me more in summer
• yellow as a color looks better on me in summer

Context usually makes the exact meaning clear.