*{margin:0;padding:0;box-sizing:border-box}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif;background-color:#f5f5f5;color:#333}#app{max-width:480px;margin:0 auto;min-height:100vh;background:#fff;box-shadow:0 0 10px #0000001a}.container{padding:20px}.header{background:#007aff;color:#fff;padding:20px;text-align:center}.form-group{margin-bottom:20px}label{display:block;margin-bottom:8px;font-weight:700}select,input,textarea{width:100%;padding:12px;border:1px solid #ddd;border-radius:8px;font-size:16px}textarea{resize:vertical;min-height:100px}.btn{background:#007aff;color:#fff;border:none;padding:14px 24px;border-radius:8px;font-size:16px;cursor:pointer;width:100%}.btn:hover{background:#0056cc}.messages{margin-top:20px;max-height:300px;overflow-y:auto}.message{background:#e3f2fd;padding:12px;margin-bottom:10px;border-radius:8px;border-left:4px solid #007aff}.message-sender{font-weight:700;color:#007aff;margin-bottom:5px}.contact-list{list-style:none}.contact-item{padding:12px;margin-bottom:8px;background:#f9f9f9;border-radius:8px;border:2px solid transparent;cursor:pointer}.contact-item:hover{background:#f0f0f0}.contact-item.selected{border-color:#007aff;background:#e3f2fd}