Sprited by KL, thanks man.

He's got a costume in reversed colors for missions where it's more suitable.

He's kind of pale (which has to do with his powers; he just doesn't tan well), with piercing blue-grey eyes. He stands at 6 feet exactly, and is well-built, having been a gymnast since he was 6. He's got a strong chin, usually with light but scruffy stubble, and prominent cheekbones. His hair is medium-short, dark brown, and styles it up out of his face when he can help it (his mask screws it up every time).

Beck had always idolized superheroes. One night in Gotham, he'd been walking home from the movies when a police car sped past. Hoping it would be his chance to see some superhuman action, he followed it to an old warehouse. Luckily, the police were only just arriving, and he was able to slip in a window in the back.
He hid behind a large stack of crates as he saw them, Batman and Mr. Freeze locked in combat. Beck stood up and tried to move to a better position to watch, while Batman happened to dodge a blast from the Freeze Gun right in front of him. The stray blast hit Beck, and he fell unconscious. He came to briefly, being carried out of the warehouse by none other than his hero, though he slipped away again quickly. He was cold.
When he awoke, he was in a hospital bed, though it seemed more like a lab than a hospital. Batman was standing beside the bed, and after making sure Beck's vitals were okay, scolded him for being so reckless. Irresponsible, he said, and incredibly stupid. But it was too late, the mistake was made.
The blast had altered something in his genetics, and he would now need what was essentially a special antifreeze injected into his body every 48 hours to avoid harm. However, he could take advantage of his situation. Tap into it, and use the freezing effect as a gift. That was the condition Batman set; so long as Beck trained under Ice, a member of the Justice League, he'd continue recieving the serum to stay alive.
This was six years ago for Beck, and while he's started a decent solo career in the past couple years, Ice felt that the new Young Justice program had come in perfect time for him to prove his worth to the Justice League.

The Bat stood beside the hospital bed.
"Beck. There's someone I'd like you to meet."

Beck looked up at him, and then at the doorway as the person stepped inside. She wore a blue and white suit, and had snow white hair. Ice.

"Hi, honey. You must be Beck."

Beck nodded. It was all he could do, really. He was completely starstruck. Ice seemed to find this amusing, thought Batman didn't seem to share the sentiment.

"Well, then. Let's get you home so we can tell your parents about our arrangement. Oh, and, don't worry, they already know where you are."

--- 6 Years Later ---

"Beck!"
"Coming! Just, one sec!"
"You're going to be late!"
"We already are late, Tora!"
"That doesn't mean you get to be as late as you want now, though!"
"Alright, sorry, I'm good now. Let's go."

The pair skated on an ice platform together high above Star City. Soon enough, they landed just outside the tower.

"So, Young Justice," Beck started. "Who else is in this, again?"
Tora (Ice) looked at him. "We've been over this at least three times. Trust me. They're alright." Her eyes flicked to the tower for a moment, then back to him. "Probably."
"Probably?"
"More like hopefully."
"Cut that out."

She smirked, but then suddenly became serious and put a hand on his shoulder. "This is your next step, Beck. If you prove yourself here, you're on the way to League status. Just remember everything I've taught you."
"Don't worry. I'll see you soon, okay?" He smiled and hugged her, and then started to turn around and walk inside.
"Oh, and Beck?"
He looked over his shoulder.
"Make me proud."