Oh, that aquamarine! No hotel lobby does justice to the Rat Pack era like the Eden Roc does. It doesn't look seedy and it doesn't feel old. It looks wonderfully fresh, as if you just walked through the doors to 1956. The Eden Roc, a Morris Lapidus jewel built in that year, does not offer an icy chrome entrance like so many of the earlier hotels further south on the Beach. No, this lobby comes from a time when cars had big fins and guests carried big drinks (it has blue-green carpeting, for God's sake). It's not just the sea color that makes you want to sink back into this world for hours. It's also something about the shape of the chairs, the placement of the pillars, the rust-and-gold diamonds on the walls, the white-and-green lamps, the piano, all those Grecian accessories. But get your fill of sitting in Eden soon, because starting sometime this summer the lobby will be renovated. The bright and light will be replaced, a spokeswoman says, by "stronger" colors like beige and black. Like all those hotels further south. We've already had to say so long to Frank, Sammy, and Dean. Must we lose this gem, too?