/* ========== 基础重置与变量 ========== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --bg-primary: #0a0a0f;
  --bg-secondary: #13131a;
  --bg-input: #1c1c27;
  --bg-message-own: #1a1a40;
  --bg-message-other: #1e1e2e;
  --accent: #6c5ce7;
  --accent-hover: #5a4bd1;
  --accent-glow: rgba(108, 92, 231, 0.3);
  --text-primary: #e8e8f0;
  --text-secondary: #94a3b8;
  --text-muted: #44445a;
  --border: #2a2a3d;
  --danger: #ef4444;
  --success: #00d2d3;
  --radius: 16px;
  --radius-sm: 10px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  height: 100vh;
  overflow: hidden;
}

.hidden { display: none !important; }

/* ========== 消息列表 ========== */
.messages {
  flex: 1;
  overflow-y: auto;
  padding: 16px 20px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  scroll-behavior: smooth;
}

.messages::-webkit-scrollbar { width: 6px; }
.messages::-webkit-scrollbar-track { background: transparent; }
.messages::-webkit-scrollbar-thumb { background: var(--border); border-radius: 3px; }

/* ========== 单条消息 ========== */
.message {
  display: flex;
  flex-direction: column;
  max-width: 80%;
  animation: fadeIn 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to   { opacity: 1; transform: translateY(0); }
}

.message.own {
  align-self: flex-end;
  align-items: flex-end;
}

.message.other {
  align-self: flex-start;
  align-items: flex-start;
}

.message-meta {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-bottom: 3px;
  padding: 0 4px;
}

.message.own .message-meta { justify-content: flex-end; }

.message-username {
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--accent);
}

.message-time {
  font-size: 0.72rem;
  color: var(--text-muted);
}

.message-bubble {
  padding: 10px 14px;
  border-radius: var(--radius);
  word-break: break-word;
  line-height: 1.55;
  font-size: 0.95rem;
  white-space: pre-wrap;
}

.message.own .message-bubble {
  background: linear-gradient(135deg, var(--accent), var(--accent-hover));
  color: #fff;
  border-bottom-right-radius: 4px;
  box-shadow: 0 4px 15px var(--accent-glow);
}

.message.other .message-bubble {
  background: var(--bg-message-other);
  border: 1px solid var(--border);
  border-bottom-left-radius: 4px;
  color: var(--text-primary);
}

/* 系统消息 */
.message.system .message-bubble {
  align-self: center;
  background: transparent;
  border: none;
  color: var(--text-muted);
  font-size: 0.82rem;
  font-style: italic;
  text-align: center;
  padding: 6px 14px;
}

/* ========== 输入区 ========== */
.input-area {
  display: flex;
  align-items: flex-end;
  gap: 10px;
  padding: 12px 16px;
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  flex-shrink: 0;
}

.message-input {
  flex: 1;
  padding: 12px 16px;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text-primary);
  font-size: 0.95rem;
  font-family: inherit;
  resize: none;
  outline: none;
  max-height: 120px;
  line-height: 1.4;
  transition: border-color 0.2s, box-shadow 0.2s;
}

.message-input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-glow);
}

.message-input::placeholder { color: var(--text-muted); }

.btn-send {
  width: 46px;
  height: 46px;
  background: linear-gradient(135deg, var(--accent), var(--accent-hover));
  border: none;
  border-radius: var(--radius-sm);
  color: #fff;
  font-size: 1.2rem;
  cursor: pointer;
  flex-shrink: 0;
  transition: all 0.2s;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 15px var(--accent-glow);
}

.btn-send:hover:not(:disabled) { transform: scale(1.05); }
.btn-send:active:not(:disabled) { transform: scale(0.95); }
.btn-send:disabled { background: var(--border); cursor: not-allowed; opacity: 0.5; box-shadow: none; }

/* ========== 空状态 ========== */
.empty-state {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  gap: 12px;
}

.empty-state .icon { font-size: 3rem; opacity: 0.5; }
.empty-state .text { font-size: 0.95rem; }

/* ========== 快捷回复 ========== */
.quick-replies {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding: 8px 16px;
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
}

.quick-chip {
  background: var(--bg-input);
  border: 1px solid var(--border);
  color: var(--accent);
  padding: 7px 14px;
  border-radius: 20px;
  font-size: 13px;
  cursor: pointer;
  transition: all 0.2s;
  white-space: nowrap;
}

.quick-chip:hover {
  background: rgba(108, 92, 231, 0.15);
  border-color: var(--accent);
  color: var(--accent-hover);
}

/* ========== 响应式 ========== */
@media (max-width: 600px) {
  .messages { padding: 12px 10px; }
  .message { max-width: 88%; }
  .input-area { padding: 10px; }
  .quick-replies { padding: 8px 10px; }
}