gelungen
successful
Describes something that was successful, well made, or had a positive result. It is used for events, works, plans, or even food.
Das Fest war eine rundum gelungene Veranstaltung.
The party was a thoroughly successful event.

successful / well-done
Loading your saved state.
successful
Describes something that was successful, well made, or had a positive result. It is used for events, works, plans, or even food.
Das Fest war eine rundum gelungene Veranstaltung.
The party was a thoroughly successful event.

'Gelungen' (successful/well-done) is the past participle of the verb 'gelingen' (to succeed). When something 'gelungen ist' (has succeeded), it was successful. The adjective therefore directly describes the result of this verb.
Die Überraschung ist uns wirklich gelungen.
The surprise really worked out well for us.
The verb 'gelingen' (to succeed) needs a person in the dative to say who was successful, e.g. 'Das Bild ist mir gelungen.' (The picture turned out well for me / I succeeded with the picture). Even though the adjective is often used without the dative, this structure helps you understand the meaning.
Mir ist heute ein sehr gutes Essen gelungen.
I managed to make a very good meal today.
'Gelungen' (successful/well-done) is often used to describe the positive result of events, creative works, or actions. Typical combinations are 'ein gelungener Abend' (a successful evening), 'eine gelungene Feier' (a successful celebration), or 'ein gelungenes Foto' (a successful photo).
Das war wirklich eine gelungene Überraschungsparty!
That really was a successful surprise party!
When 'gelungen' (a real character) describes a person, it is colloquial and often meant slightly ironically or affectionately. It describes someone who is special in a funny or clever way.
Mit seinen frechen Antworten ist er ein wirklich gelungener Typ.
With his cheeky answers, he is a real character.
good
'gut' and 'gelungen' can both say that something is positive. 'gut' is very general and fits many things: a plan, a meal, an idea, or a performance. 'gelungen' is more precise when something was made, planned, or designed and the result is successful. For example, you say 'eine gelungene Feier' (a successful party) or 'ein gelungener Text' (a well-done text). 'gut' gives a more general evaluation, while 'gelungen' emphasizes: it worked and turned out nice or suitable.

Zur Vorbereitung hat das Team eine gelungene Präsentation erstellt.
To prepare, the team created a successful presentation.
Deine Idee für das Projekt ist gut.
Your idea for the project is good.