:root {
  --bg: #0f0f14;
  --bg-grad: radial-gradient(ellipse at top, #1a1a2e 0%, #0f0f14 55%);
  --card: #1a1a24;
  --card-border: #2a2a38;
  --gold: #d4af37;
  --gold-soft: #e6c96a;
  --red: #c0392b;
  --ink: #ece9e2;
  --muted: #9a97a0;
  --user-bubble: #c9a04a;
  --user-text: #1a1408;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html, body {
  height: 100%;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--ink);
}

.chat-app {
  display: flex;
  flex-direction: column;
  height: 100dvh;
  max-width: 720px;
  margin: 0 auto;
  background: var(--bg-grad);
  position: relative;
}

/* 头部 */
.chat-header {
  padding: 14px 16px 12px;
  border-bottom: 1px solid var(--card-border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: rgba(15,15,20,0.7);
  backdrop-filter: blur(10px);
  position: sticky;
  top: 0;
  z-index: 10;
}
.brand h1 {
  font-size: 20px;
  letter-spacing: 2px;
  background: linear-gradient(90deg, var(--gold-soft), var(--gold));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  font-weight: 700;
}
.brand .slogan {
  font-size: 11px;
  color: var(--muted);
  letter-spacing: 0.5px;
  margin-top: 2px;
}
.status-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--gold);
  box-shadow: 0 0 8px var(--gold);
  animation: pulse 2s infinite;
}
@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}

/* 聊天区 */
.chat-body {
  flex: 1;
  overflow-y: auto;
  padding: 16px 14px 20px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  scroll-behavior: smooth;
}
.chat-body::-webkit-scrollbar { width: 4px; }
.chat-body::-webkit-scrollbar-thumb { background: var(--card-border); border-radius: 2px; }

/* 气泡 */
.msg { display: flex; max-width: 86%; animation: rise 0.25s ease; }
@keyframes rise { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: translateY(0); } }

.msg.ai { align-self: flex-start; }
.msg.user { align-self: flex-end; }

.bubble {
  padding: 11px 14px;
  border-radius: 16px;
  line-height: 1.65;
  font-size: 15px;
  word-break: break-word;
  white-space: pre-wrap;
}
.msg.ai .bubble {
  background: var(--card);
  border: 1px solid var(--card-border);
  border-top-left-radius: 4px;
  color: var(--ink);
}
.msg.user .bubble {
  background: var(--user-bubble);
  color: var(--user-text);
  border-top-right-radius: 4px;
}

/* AI 气泡里的金色关键词 */
.msg.ai .bubble .hl {
  color: var(--gold-soft);
  font-weight: 600;
}

/* 打字动画 */
.typing { display: inline-flex; gap: 4px; padding: 4px 0; }
.typing span {
  width: 6px; height: 6px; border-radius: 50%;
  background: var(--gold);
  animation: blink 1.2s infinite;
}
.typing span:nth-child(2) { animation-delay: 0.2s; }
.typing span:nth-child(3) { animation-delay: 0.4s; }
@keyframes blink { 0%, 60%, 100% { opacity: 0.3; } 30% { opacity: 1; } }

/* 输入区 */
.chat-input {
  display: flex;
  gap: 10px;
  padding: 12px 14px;
  border-top: 1px solid var(--card-border);
  background: rgba(15,15,20,0.7);
  backdrop-filter: blur(10px);
  position: sticky;
  bottom: 0;
}
.chat-input input {
  flex: 1;
  padding: 12px 16px;
  border-radius: 24px;
  border: 1px solid var(--card-border);
  background: var(--card);
  color: var(--ink);
  font-size: 15px;
  outline: none;
  transition: border-color 0.2s;
}
.chat-input input:focus { border-color: var(--gold); }
.chat-input input::placeholder { color: var(--muted); }
.chat-input button {
  padding: 12px 20px;
  border-radius: 24px;
  border: none;
  background: linear-gradient(90deg, var(--gold), var(--gold-soft));
  color: #1a1408;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.1s, opacity 0.2s;
}
.chat-input button:active { transform: scale(0.96); }
.chat-input button:disabled { opacity: 0.5; cursor: not-allowed; }

/* 移动端适配 */
@media (max-width: 480px) {
  .brand h1 { font-size: 18px; }
  .bubble { font-size: 14.5px; }
  .chat-input input { font-size: 14px; }
}