Brúðkaupið er lítið en mjög fallegt.

to be

Breakdown of Brúðkaupið er lítið en mjög fallegt.

• lítill: small
• fallegur: beautiful
• mjög: very

Questions & Answers about Brúðkaupið er lítið en mjög fallegt.

Why does Brúðkaupið end in -ið instead of having a separate word for “the”?

Icelandic usually attaches the definite article as an ending instead of using a separate word like English the.
Brúðkaup is a neuter noun meaning wedding, and the neuter definite ending in the nominative singular is -ið.
So brúðkaup → brúðkaupið = the wedding.

What gender is brúðkaup, and how does that affect the sentence?

Brúðkaup is a neuter noun.
Because the subject is neuter singular, the describing adjectives (lítið, fallegt) also have to be in the neuter singular nominative form.
That is why you see -t at the end of both adjectives.

Why is it lítið and not lítill or lítil?

The base form of the adjective is lítill (m.), lítil (f.), lítið (n.) = small.
Since brúðkaupið is neuter, you must choose the neuter form: lítið.
If the subject were masculine or feminine, you would use lítill or lítil instead.