#cv-chat-btn {
  position: fixed; right: 18px; bottom: 18px; z-index: 10000;
  width: 56px; height: 56px; border-radius: 50%; border: none; cursor: pointer;
  background: #2c8ac9; color: #fff; font-size: 26px; line-height: 56px; text-align: center;
  box-shadow: 0 2px 10px rgba(0,0,0,.3); opacity: .9; transition: opacity .3s, transform .2s;
}
#cv-chat-btn:hover { opacity: 1; transform: scale(1.06); }

#cv-chat-panel {
  position: fixed; right: 18px; bottom: 84px; z-index: 10000;
  width: 360px; max-width: calc(100vw - 36px); height: 550px; max-height: calc(100vh - 110px);
  display: none; flex-direction: column; background: #fff; border-radius: 10px;
  box-shadow: 0 4px 24px rgba(0,0,0,.35); overflow: hidden;
  font-family: Arial, Helvetica, sans-serif; font-size: 14px;
}
#cv-chat-panel.cv-open { display: flex; }

.cv-chat-header {
  background: #2c8ac9; color: #fff; padding: 12px 14px; font-weight: bold; flex: 0 0 auto;
}
.cv-chat-header small { display: block; font-weight: normal; opacity: .85; font-size: 11px; }

.cv-chat-log { flex: 1 1 auto; overflow-y: auto; padding: 12px; background: #f5f7f9; }

.cv-msg { margin: 0 0 8px; padding: 8px 11px; border-radius: 10px; max-width: 85%;
  white-space: pre-wrap; word-wrap: break-word; clear: both; }
.cv-msg-user { background: #2c8ac9; color: #fff; float: right; border-bottom-right-radius: 3px; }
.cv-msg-assistant { background: #fff; color: #222; float: left; border: 1px solid #dde3e8;
  border-bottom-left-radius: 3px; }
.cv-msg-human { background: #e8f4e8; color: #1c4620; float: left; border: 1px solid #bcd9bc;
  border-bottom-left-radius: 3px; }
.cv-msg-event { background: none; color: #778; float: none; max-width: 100%;
  text-align: center; font-size: 12px; font-style: italic; }
.cv-msg-label { display: block; font-size: 10px; opacity: .7; margin-bottom: 2px; }
.cv-typing { color: #99a; font-style: italic; }

.cv-chat-form { display: flex; border-top: 1px solid #dde3e8; flex: 0 0 auto; }
.cv-chat-form input {
  flex: 1 1 auto; border: none; padding: 12px; font-size: 14px; outline: none; min-width: 0;
}
.cv-chat-form button {
  flex: 0 0 auto; border: none; background: #2c8ac9; color: #fff; padding: 0 18px;
  cursor: pointer; font-size: 14px;
}
.cv-chat-form button:disabled { background: #9bc4de; cursor: default; }

@media (max-width: 480px) {
  #cv-chat-panel {
    right: 0; bottom: 0; width: 100vw; max-width: 100vw; height: 100vh; max-height: 100vh;
    border-radius: 0;
  }
}