:root {
  --bg: #f5f0e8;
  --card: #fffef9;
  --text: #3d3226;
  --text-light: #6b5e4e;
  --accent: #8b4513;
  --accent-light: #b8860b;
  --border: #d4c5a9;
  --shadow: 0 2px 12px rgba(0,0,0,0.06);
  --input-bg: #fffef9;
  --tag-bg: #f0e6d3;
  --danger: #c0392b;
  --success: #2d6a4f;
}
[data-theme="dark"] {
  --bg: #1a1814;
  --card: #252320;
  --text: #ddd2c0;
  --text-light: #a89880;
  --accent: #d4945a;
  --accent-light: #e8b960;
  --border: #3d3528;
  --shadow: 0 2px 12px rgba(0,0,0,0.3);
  --input-bg: #2a2722;
  --tag-bg: #333028;
}
* { margin:0; padding:0; box-sizing:border-box; }
body {
  font-family: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "SimSun", "KaiTi", serif;
  background: var(--bg); color: var(--text);
  min-height: 100vh; line-height: 1.7;
  -webkit-text-size-adjust: 100%;
}
.header {
  background: var(--card); border-bottom: 1px solid var(--border);
  padding: 12px 16px; display: flex; align-items: center; justify-content: space-between;
  box-shadow: var(--shadow); position: sticky; top:0; z-index:100;
  flex-wrap: wrap; gap: 8px;
}
.header h1 { font-size: 1.1rem; font-weight: 600; color: var(--accent); letter-spacing: 0.02em; line-height: 1.3; }
.header h1 span { font-size: 0.8rem; color: var(--text-light); font-weight: 400; margin-left: 8px; }
.header-actions { display:flex; gap:10px; align-items:center; }
.header-actions button {
  background: none; border: 1px solid var(--border); color: var(--text-light);
  padding: 8px 14px; border-radius: 6px; cursor: pointer; font-size: 0.85rem;
  font-family: inherit; transition: all 0.2s;
  min-height: 40px; touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
}
.header-actions button:hover { background: var(--tag-bg); color: var(--text); }
.container { max-width: 720px; margin: 0 auto; padding: 16px 12px; }
.main { width: 100%; }
.card {
  background: var(--card); border: 1px solid var(--border);
  border-radius: 10px; padding: 16px; margin-bottom: 14px; box-shadow: var(--shadow);
}
.card-title {
  font-size: 1rem; font-weight: 600; color: var(--accent);
  margin-bottom: 14px; padding-bottom: 10px;
  border-bottom: 1px solid var(--border); letter-spacing: 0.03em;
}
.form-group { margin-bottom: 14px; }
.form-group label {
  display: block; font-size: 0.88rem; color: var(--text-light);
  margin-bottom: 5px; font-weight: 500;
}
.form-group select, .form-group input, .form-group textarea {
  width: 100%; padding: 11px 12px;
  border: 1px solid var(--border); border-radius: 8px;
  background: var(--input-bg); color: var(--text);
  font-size: max(0.92rem, 16px); font-family: inherit;
  transition: border-color 0.2s;
  -webkit-appearance: none;
}
.form-group select { -webkit-appearance: auto; }
.form-group select:focus, .form-group input:focus, .form-group textarea:focus {
  outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px rgba(139,69,19,0.1);
}
.form-group textarea { resize: vertical; min-height: 80px; }
.yao-selector { display: flex; gap: 8px; flex-wrap: wrap; }
.yao-btn {
  width: 40px; height: 40px; border-radius: 50%;
  border: 2px solid var(--border); background: var(--input-bg);
  color: var(--text); font-size: 0.9rem; cursor: pointer;
  transition: all 0.2s; display: flex; align-items: center; justify-content: center;
  font-family: inherit;
}
.yao-btn:hover { border-color: var(--accent); }
.yao-btn.active { background: var(--accent); color: #fff; border-color: var(--accent); }
.yao-btn.yin { background: #2a2a2a; color: #ccc; }
.yao-btn.yin.active { background: #555; color: #fff; border-color: #555; }
.yao-labels { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 4px; }
.yao-labels span { width: 40px; text-align: center; font-size: 0.72rem; color: var(--text-light); }
.btn {
  padding: 12px 24px; border-radius: 8px; border: none;
  font-size: 1rem; font-family: inherit; cursor: pointer;
  transition: all 0.2s; font-weight: 500; letter-spacing: 0.02em;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
}
.btn-primary { background: var(--accent); color: #fff; width: 100%; margin-top: 4px; min-height: 48px; }
.btn-primary:hover { opacity: 0.9; transform: translateY(-1px); }
.btn-primary:disabled { opacity: 0.5; cursor: not-allowed; transform: none; }
.btn-sm {
  padding: 10px 18px; border-radius: 8px; border: none;
  font-size: max(0.9rem, 14px); font-family: inherit; cursor: pointer;
  background: var(--accent); color: #fff; font-weight: 500;
  transition: all 0.2s; white-space: nowrap; min-height: 44px;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
}
.btn-sm:hover { opacity: 0.9; }
.num-row {
  display: flex; gap: 10px; align-items: flex-end;
}
.num-row .form-group { flex: 1; }
.num-row .btn-sm { margin-bottom: 14px; }
.num-result {
  margin-top: 6px; padding: 10px 12px; border-radius: 6px;
  background: var(--tag-bg); font-size: 0.85rem; color: var(--text);
  display: none; line-height: 1.7;
}
.num-result.visible { display: block; }
.result-card { display: none; }
.result-card.visible { display: block; }
.result-body {
  font-size: 0.93rem; line-height: 1.9;
  white-space: normal; color: var(--text);
  word-break: break-word;
}
.result-body p {
  margin-bottom: 0.9em; text-indent: 0;
}
.result-body p:last-child { margin-bottom: 0; }
.result-body .loading { color: var(--text-light); font-style: italic; }
.result-body strong { color: var(--accent); }
.result-body u {
  text-decoration: none;
  border-bottom: 2px solid var(--accent-light);
  padding-bottom: 1px;
}
.error-msg { color: var(--danger); font-size: 0.9rem; margin-top: 8px; }
.result-footer { margin-top: 8px; }
.btn-copy {
  display: block; margin: 12px auto 0;
  padding: 10px 28px; border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--input-bg); color: var(--text);
  font-size: 0.88rem; font-family: inherit; cursor: pointer;
  transition: all 0.25s;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
}
.btn-copy:hover { background: var(--tag-bg); border-color: var(--accent); }
.btn-copy.copied { background: var(--accent); color: #fff; border-color: var(--accent); }
.tooltip { font-size: 0.8rem; color: var(--text-light); margin-top: 2px; line-height: 1.5; }
.theme-toggle { background: none; border: none; font-size: 1.2rem; cursor: pointer; padding: 4px 8px; }
.collapse-header {
  cursor: pointer; display: flex; align-items: center; gap: 8px;
  user-select: none; color: var(--accent);
}
.collapse-header .arrow { transition: transform 0.2s; display: inline-block; }
.collapse-header.open .arrow { transform: rotate(90deg); }
.collapse-body { display: none; margin-top: 14px; }
.collapse-body.open { display: block; }
@media (max-width: 768px) {
  .header { padding: 10px 12px; }
  .header h1 { font-size: 0.95rem; }
  .header-actions { gap: 6px; }
  .header-actions button { padding: 6px 10px; font-size: 0.8rem; }
  .container { padding: 12px 8px; }
  .card { padding: 14px; margin-bottom: 10px; border-radius: 8px; }
  .card-title { font-size: 0.95rem; margin-bottom: 10px; }
  .num-row { flex-direction: column; gap: 0; }
  .num-row .form-group { margin-bottom: 8px; }
  .num-row .btn-sm { width: 100%; margin-bottom: 8px; }
  .form-group { margin-bottom: 10px; }
  .form-group label { font-size: 0.82rem; }
  .result-body { font-size: 0.88rem; }
}
@media (max-width: 400px) {
  .header h1 { font-size: 0.85rem; }
  .card { padding: 12px; }
}
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border); border-radius: 3px; }

/* ============ 认证弹窗 ============ */
.modal {
  display: none; position: fixed; z-index: 200;
  left: 0; top: 0; width: 100%; height: 100%;
  background: rgba(0,0,0,0.5);
  justify-content: center; align-items: center;
  padding: 16px;
}
.modal.visible { display: flex; }
.modal-content {
  background: var(--card); border-radius: 12px;
  padding: 28px 24px; width: 100%; max-width: 380px;
  box-shadow: 0 8px 32px rgba(0,0,0,0.2);
  position: relative; max-height: 90vh; overflow-y: auto;
}
.modal-close {
  position: absolute; top: 12px; right: 16px;
  font-size: 1.5rem; cursor: pointer; color: var(--text-light);
  line-height: 1;
}
.modal-close:hover { color: var(--text); }

.auth-tabs { display: flex; gap: 0; margin-bottom: 18px; border-bottom: 2px solid var(--border); }
.auth-tab {
  flex: 1; padding: 10px; border: none; background: none;
  font-size: 0.95rem; font-family: inherit; cursor: pointer;
  color: var(--text-light); border-bottom: 2px solid transparent;
  margin-bottom: -2px; transition: all 0.2s;
}
.auth-tab.active { color: var(--accent); border-bottom-color: var(--accent); font-weight: 600; }
.auth-input {
  width: 100%; padding: 11px 12px; margin-bottom: 10px;
  border: 1px solid var(--border); border-radius: 8px;
  background: var(--input-bg); color: var(--text);
  font-size: max(0.95rem, 16px); font-family: inherit;
}
.auth-input:focus { outline: none; border-color: var(--accent); }
.auth-error { color: var(--danger); font-size: 0.82rem; margin-bottom: 10px; min-height: 1.2em; }

/* ============ 用户菜单 ============ */
.user-info {
  font-size: 0.85rem; color: var(--accent); cursor: pointer;
  padding: 6px 10px; border: 1px solid var(--border); border-radius: 6px;
  white-space: nowrap;
}
.user-info:hover { background: var(--tag-bg); }
.user-menu {
  position: absolute; top: 100%; right: 16px;
  background: var(--card); border: 1px solid var(--border);
  border-radius: 8px; box-shadow: 0 4px 16px rgba(0,0,0,0.12);
  z-index: 150; min-width: 140px; overflow: hidden;
}
.user-menu a {
  display: block; padding: 10px 16px; color: var(--text);
  text-decoration: none; font-size: 0.88rem; transition: background 0.15s;
  border-bottom: 1px solid var(--border);
}
.user-menu a:last-child { border-bottom: none; }
.user-menu a:hover { background: var(--tag-bg); }

/* ============ 历史记录面板 ============ */
.history-modal { max-width: 600px; }
.history-item {
  padding: 12px; border: 1px solid var(--border); border-radius: 8px;
  margin-bottom: 8px; cursor: pointer; transition: all 0.15s;
}
.history-item:hover { border-color: var(--accent); background: var(--tag-bg); }
.history-meta { font-size: 0.75rem; color: var(--text-light); margin-bottom: 4px; }
.history-question { font-size: 0.9rem; color: var(--accent); font-weight: 500; margin-bottom: 4px; }
.history-preview { font-size: 0.8rem; color: var(--text-light); line-height: 1.5; }
.history-detail { margin-top: 8px; }
.history-question-full { font-size: 1rem; color: var(--accent); font-weight: 600; margin-bottom: 14px; padding-bottom: 12px; border-bottom: 1px solid var(--border); }
.history-answer { font-size: 0.9rem; line-height: 1.9; color: var(--text); }

@media (max-width: 768px) {
  .modal-content { padding: 20px 16px; }
  .header-actions { position: relative; }
}