...and so absorbed in the moment you lost all self-consciousness. (Para. 5)
be absorbed (in): give all one's attention (to) sth.
The artist was so absorbed in her work that she didn't hear her visitor enter the room. 這位藝術家聚精會神于自己的工作，以至于沒有聽到來訪者進了房間。
Time passes quickly when you are absorbed in reading a good book. 當你全神貫注閱讀一本好書時，時間會過得很快。
The structure "so + adj. /adv. +(that)" is used to express "to such a degree as to produce a particular result, causing a particular situation, etc. For example,
He was so ill (that) we had to send for a doctor. 他病得很重，我們得派人去請醫生。