I'm surprised there isn't any english translations for this song yet. I found that AnimeLyrics has the kanji & english translations, and I just wanted to share this with those who weren't aware...

Kanji:

黒き果てしのない 闇の風聞いたら
白き永遠の光の海へ

七色の架け橋 どこかに隠された鍵
空高く訪れる 人の知らない世界

時隔てた誓い 涙の調べ
心輝かす 浅葱色の約束

語ろう 今碧く燃えゆく
胸の奥 赤錆びた壁打ち破り

飛びたて なにもかも脱ぎ捨てて
汚れのない翼がちぎれるまで…

金色の潮風 いずこに流された島
空と空結んでる 誰もいない楽園

明日導く願い 命の叫び
ふたりもとめあう 萌葱色のやすらぎ

祝おう 翠を愛してる仲間たち
手をつなぎ ひとつになろう

目覚めよ 透きとおるさざ波の唄
くちずさめばすぐ生まれかわる…

English:

Listening to the wind of black endless darkness,
we head towards a sea of white eternal light.

Somewhere on that rainbow bridge, a key has been hidden.
High in the sky, we're in an unfamiliar world unknown to anyone.

Our oath, after the lapse of time, resounds in the melody of tears.
It is a teal-colored promise that illuminates our heart.

Let's recite our oath. As we blaze in a jade-green glow,
we will shatter that red rusty wall buried deep within our heart.

Now take off into the sky, and throw away everything else,
until our unsullied wings begin to tear off...

In the golden sea breeze, we have drifted onto a remote island.
It is a vacant paradise where the skies meet and merge.

Our wish, led by tomorrow, is our howl for life.
It is a lime-colored tranquility that stops us in our tracks.

Let's celebrate. Oh my friends who admire the color green,
let's hold our hands and unite as one.

Awaken now. As soon as we hum the song
of the clear ripples, we will be reborn...

Translations are provided by Animeyay.