/* Paper Explorer — 侘寂风 */
:root {
  --ink: #f5f1e8;
  --ink-light: #aab3aa;
  --mist: rgba(190, 211, 178, .10);
  --snow: #050908;
  --blue: #d7e8c6;
  --blue-dim: #6f8f79;
  --border: rgba(235, 244, 226, .14);
  --radius: 18px;
  --serif: 'Cormorant Garamond', 'Georgia', 'Noto Serif SC', serif;
  --sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Noto Sans SC', sans-serif;
  --sidebar-w: 220px;
}

html, body {
  margin: 0;
  padding: 0;
  width: 100%;
  height: 100vh;
  max-height: 100vh;
  overflow: hidden;
}
* { margin: 0; padding: 0; box-sizing: border-box; }

body {
  font-family: var(--sans);
  color: var(--ink);
  background: #000;
  line-height: 1.7;
  position: relative;
}

/* 粒子画布 — 固定视口，永远不滚动 */
#bg-canvas {
  position: fixed;
  top: 0; left: 0;
  width: 100vw;
  height: 100vh;
  z-index: 0;
  pointer-events: none;
}

/* 整体布局 — 填满视口 */
.app-layout {
  position: relative;
  z-index: 1;
  display: flex;
  width: 100%;
  height: 100vh;
  max-height: 100vh;
  overflow: hidden;
}

/* ── 侧边栏 ── */
.sidebar {
  width: var(--sidebar-w);
  background: rgba(4, 7, 7, .72);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  padding: 24px 0;
  position: fixed;
  top: 0; left: 0; bottom: 0;
  z-index: 100;
}
.sidebar .logo {
  font-family: var(--serif);
  font-size: 18px;
  font-weight: 400;
  color: var(--ink);
  letter-spacing: 1px;
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 0 24px 22px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 14px;
}
.logo-icon {
  width: 28px;
  height: 28px;
  flex-shrink: 0;
  color: var(--blue);
}
.sidebar .logo span { color: var(--blue); }

.side-nav {
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  gap: 5px;
  padding: 0 14px;
}
.side-item {
  display: flex;
  align-items: center;
  gap: 11px;
  padding: 11px 14px;
  border-radius: 999px;
  text-decoration: none;
  color: var(--ink-light);
  font-size: 14px;
  transition: all 0.15s;
}
.side-item:hover { background: rgba(219, 234, 207, .09); color: var(--ink); }
.side-item.active { background: #f4f0e8; color: #050706; }
.side-icon { font-size: 16px; }

.side-footer {
  padding: 18px 20px;
  border-top: 1px solid var(--border);
  flex-shrink: 0;
}
.side-user {
  display: block;
  font-size: 13px;
  color: var(--ink-light);
  margin-bottom: 8px;
}

/* ── 搜索历史 ── */
.side-history {
  flex: 1;
  overflow-y: auto;
  padding: 0 14px;
  margin-top: 8px;
}
.side-history-title {
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: rgba(245,241,232,.3);
  padding: 6px 8px;
}
.side-history-list {
  display: flex;
  flex-direction: column;
  gap: 2px;
}
.side-history-item {
  display: block;
  padding: 6px 10px;
  font-size: 12px;
  color: var(--ink-light);
  text-decoration: none;
  border-radius: 8px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  transition: all 0.12s;
}
.side-history-item:hover {
  background: rgba(219, 234, 207, .09);
  color: var(--ink);
}

/* ── 主内容（唯一可滚动区域）── */
.main-content {
  flex: 1;
  min-height: 0;
  margin-left: var(--sidebar-w);
  overflow-y: auto;
  overflow-x: hidden;
  position: relative;
  z-index: 1;
}

/* ── 按钮 ── */
.btn {
  display: inline-block;
  padding: 10px 22px;
  border-radius: 999px;
  font-size: 14px;
  text-decoration: none;
  border: none;
  cursor: pointer;
  transition: all 0.2s;
}
.btn-primary { background: #f4f0e8; color: #050706; }
.btn-primary:hover { background: var(--blue); }
.btn-outline { background: rgba(255,255,255,.03); border: 1px solid var(--border); color: var(--ink); }
.btn-outline:hover { border-color: var(--blue); color: var(--blue); }
.btn-ghost { background: rgba(255,255,255,.02); color: var(--ink-light); padding: 5px 12px; }
.btn-ghost:hover { color: var(--ink); }

/* ── 主容器 ── */
.container {
  max-width: 780px;
  margin: 0 auto;
  padding: 56px 24px;
}
.page-title {
  font-family: var(--serif);
  font-size: 26px;
  font-weight: 400;
  margin-bottom: 10px;
}

/* ── 搜索框 ── */
.search-box {
  width: 100%;
  padding: 17px 22px;
  font-size: 16px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: rgba(255,255,255,.045);
  color: var(--ink);
  outline: none;
  transition: border-color 0.2s, box-shadow 0.2s;
}
.search-box:focus {
  border-color: var(--blue);
  box-shadow: 0 0 0 3px rgba(215,232,198,.13);
}
.search-box::placeholder { color: rgba(245,241,232,.42); }

/* ── 检索范围 ── */
.scope-group {
  display: flex;
  justify-content: center;
  gap: 26px;
  margin-top: 18px;
}
.scope-check {
  display: flex;
  align-items: center;
  gap: 7px;
  font-size: 14px;
  color: var(--ink);
  cursor: pointer;
}
.scope-check input[type="checkbox"] {
  width: 16px; height: 16px;
  accent-color: var(--blue);
}

/* ── 模式选择 ── */
.mode-group {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 7px;
  margin-top: 12px;
  transition: opacity 0.2s;
}
.mode-group.disabled {
  opacity: 0.42;
  pointer-events: none;
}
.mode-label {
  font-size: 13px;
  color: rgba(245,241,232,.48);
  margin-right: 6px;
}
.mode-pill {
  padding: 6px 18px;
  border-radius: 999px;
  font-size: 12px;
  border: 1px solid var(--border);
  cursor: pointer;
  background: rgba(255,255,255,.04);
  color: var(--ink-light);
  transition: all 0.15s;
}
.mode-pill.active { background: #f4f0e8; color: #050706; border-color: #f4f0e8; }

/* ── 模式悬浮提示 ── */
.tooltip-parent {
  position: relative;
}
.tooltip-parent::after {
  content: attr(title);
  position: absolute;
  bottom: calc(100% + 8px);
  left: 50%;
  transform: translateX(-50%);
  padding: 6px 12px;
  font-size: 11px;
  white-space: nowrap;
  color: #050706;
  background: #f4f0e8;
  border-radius: 999px;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.15s;
  z-index: 200;
}
.tooltip-parent:hover::after {
  opacity: 1;
}

/* ── 结果卡片 ── */
.result-card {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px 26px;
  margin-bottom: 14px;
  background: rgba(255,255,255,.045);
  transition: box-shadow 0.2s;
}
.result-card:hover { box-shadow: 0 18px 46px rgba(0,0,0,.34); }
.result-card .card-title { font-size: 15px; font-weight: 600; line-height: 1.5; margin-bottom: 8px; }
.result-card .card-meta { font-size: 13px; color: var(--ink-light); }
.result-card .card-meta span { margin-right: 16px; }
.result-card .card-actions { margin-top: 12px; display: flex; gap: 9px; }

/* ── 表单 ── */
.auth-card {
  max-width: 400px;
  margin: 88px auto 0;
  border: 1px solid var(--border);
  border-radius: 22px;
  padding: 42px;
  background: rgba(255,255,255,.045);
}
.auth-card h1 {
  font-family: var(--serif);
  font-size: 22px;
  text-align: center;
  margin-bottom: 30px;
  font-weight: 400;
}
.form-group { margin-bottom: 18px; }
.form-group label { display: block; font-size: 13px; color: var(--ink-light); margin-bottom: 8px; }
.form-input {
  width: 100%;
  padding: 11px 15px;
  font-size: 14px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: rgba(255,255,255,.04);
  color: #fff;
}
.form-input:focus { border-color: var(--blue); outline: none; }
.form-error { color: #ff8f83; font-size: 13px; margin-bottom: 14px; }
.code-row { display: flex; gap: 12px; align-items: flex-end; }

/* ── 对话 ── */
.chat-msg {
  max-width: 80%;
  margin-bottom: 14px;
  padding: 13px 18px;
  border-radius: 18px;
  font-size: 14px;
  line-height: 1.6;
}
.user-msg { background: #f4f0e8; color: #050706; margin-left: auto; border-bottom-right-radius: 6px; }
.ai-msg { background: rgba(255,255,255,.045); border: 1px solid var(--border); margin-right: auto; border-bottom-left-radius: 6px; }
.ai-msg h3 { font-size: 15px; margin-bottom: 10px; }
.ai-msg h4 { font-size: 14px; margin: 12px 0 6px; }
.ai-msg strong { color: var(--ink); }

/* ── 文库 ── */
.library-layout {
  display: flex;
}
.folder-panel {
  width: 220px;
  border-right: 1px solid var(--border);
  padding: 26px 18px;
  background: rgba(4, 7, 7, .72);
}
.folder-list { display: flex; flex-direction: column; gap: 5px; }
.folder-item {
  display: flex;
  align-items: center;
  gap: 9px;
  padding: 9px 13px;
  border-radius: 999px;
  font-size: 13px;
  color: var(--ink-light);
  cursor: pointer;
  transition: all 0.15s;
}
.folder-item:hover { background: rgba(219, 234, 207, .09); }
.folder-item.active { background: #f4f0e8; color: #050706; }
.folder-item.sub { padding-left: 30px; font-size: 12px; }
.folder-actions { margin-left: auto; display: none; gap: 4px; }
.folder-item:hover .folder-actions { display: flex; }
.folder-actions button {
  background: none; border: none; cursor: pointer;
  font-size: 12px; color: rgba(245,241,232,.48); padding: 2px 5px;
}
.folder-actions button:hover { color: var(--ink); }

.paper-panel {
  flex: 1;
  padding: 28px 34px;
  overflow-y: auto;
}

/* ── 加载 ── */
.spinner {
  display: inline-block;
  width: 16px; height: 16px;
  border: 2px solid var(--border);
  border-top-color: var(--blue);
  border-radius: 50%;
  animation: spin .6s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ── 响应式 ── */
@media (max-width: 640px) {
  .sidebar { width: 60px; padding: 12px 6px; }
  .sidebar .logo { font-size: 0; padding: 0 6px 12px; }
  .side-item { justify-content: center; padding: 10px 6px; font-size: 0; }
  .side-icon { font-size: 18px; }
  .main-content { margin-left: 60px; }
  .container { padding: 24px 16px; }
  .library-layout { flex-direction: column; }
  .folder-panel { width: 100%; border-right: none; border-bottom: 1px solid var(--border); }
}