Bitcoin daily Bollinger Bands slightly narrowing, short-term volatility continues to contract, indicating an imminent breakout in a single direction during the day. The four-hour chart shows small doji and small evening star alternations, with increasing bullish and bearish battles. The green candles on the rebound all have long upper shadows, indicating extremely heavy selling pressure above. Ethereum's movement is fully synchronized with Bitcoin's rhythm, with the main trend downward. The core trading strategy remains to short on rebounds.