/* APE Chat — Claude Desktop look */

.app {
  display: grid;
  grid-template-columns: 280px 1fr;
  height: 100vh;
  background: var(--bg);
}

/* ============================================================
   SIDEBAR
   ============================================================ */

.sidebar {
  background: var(--sidebar-bg);
  color: var(--sidebar-fg);
  display: flex;
  flex-direction: column;
  border-right: 1px solid var(--border);
  overflow: hidden;
}

.sidebar-header {
  padding: 18px 18px 14px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  border-bottom: 1px solid var(--border);
}

.brand-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.brand-text h1 {
  font-size: 17px;
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--text);
}
.brand-text .brand-sub {
  display: block;
  font-size: 11px;
  color: var(--muted);
  margin-top: 1px;
}

.btn-new-chat {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 9px 14px;
  font-size: 13.5px;
  font-weight: 500;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-strong);
  background: var(--surface);
  color: var(--text);
  cursor: pointer;
  transition: background 0.12s, border-color 0.12s;
}
.btn-new-chat:hover { background: var(--accent-soft); border-color: var(--primary); color: var(--primary); }

/* Session list */
.session-section {
  padding: 16px 8px 8px;
  overflow-y: auto;
  flex: 1;
}
.session-section + .session-section { padding-top: 4px; }

.session-group-title {
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--muted);
  padding: 8px 12px 6px;
}

.session-list {
  list-style: none;
  padding: 0;
  margin: 0;
}
.session-row {
  position: relative;
  display: flex;
  align-items: center;
  border-radius: var(--radius-md);
  margin-bottom: 1px;
  transition: background 0.12s;
}
.session-row:hover    { background: rgba(45,42,38,0.04); }
.session-row.active   { background: rgba(45,42,38,0.08); }

.session-link {
  flex: 1;
  text-align: left;
  background: none;
  border: none;
  padding: 8px 12px;
  cursor: pointer;
  color: var(--text);
  font-size: 13.5px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  min-width: 0;
}
.session-row.active .session-link { font-weight: 500; }

.session-del {
  background: none;
  border: none;
  color: var(--muted);
  cursor: pointer;
  padding: 4px 10px;
  font-size: 16px;
  opacity: 0;
  transition: opacity 0.15s, color 0.12s;
}
.session-row:hover .session-del { opacity: 1; }
.session-del:hover { color: var(--danger); }

/* Sidebar footer (identity + actions) */
.sidebar-footer {
  border-top: 1px solid var(--border);
  padding: 12px 14px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.identity-row {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 6px 8px;
  border-radius: var(--radius-md);
  background: rgba(45,42,38,0.04);
}
.identity-avatar {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--primary);
  color: #fff;
  font-weight: 600;
  font-size: 13px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}
.identity-input {
  flex: 1;
  border: none;
  background: none;
  font-size: 13px;
  color: var(--text);
  outline: none;
  font-family: inherit;
  min-width: 0;
}
.identity-input::placeholder { color: var(--muted); }

.sidebar-actions {
  display: flex;
  flex-direction: column;
  gap: 2px;
}
.sidebar-actions button,
.sidebar-actions a {
  width: 100%;
  text-align: left;
  background: none;
  border: none;
  font: inherit;
  color: var(--text-secondary);
  font-size: 12.5px;
  padding: 6px 10px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background 0.12s, color 0.12s;
}
.sidebar-actions button:hover,
.sidebar-actions a:hover { background: rgba(45,42,38,0.05); color: var(--text); }
.sidebar-actions button.danger:hover { color: var(--danger); }

/* ============================================================
   CHAT PANE
   ============================================================ */

.chat {
  display: flex;
  flex-direction: column;
  height: 100vh;
  background: var(--bg);
  overflow: hidden;
}

.chat-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 14px 28px;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}
.chat-header h2 {
  font-size: 14px;
  font-weight: 500;
  color: var(--text);
}
.chat-header .muted {
  font-size: 12px;
  color: var(--muted);
}

.status {
  display: flex;
  align-items: center;
  font-size: 12px;
  color: var(--muted);
}
.dot {
  display: inline-block;
  width: 7px; height: 7px;
  border-radius: 50%;
  margin-right: 7px;
  background: #c0bdb5;
}
.dot.ok  { background: var(--pos); }
.dot.err { background: var(--danger); }

/* Messages — Claude Desktop style: centered column, no bubbles for assistant */

.messages {
  flex: 1;
  overflow-y: auto;
  padding: 32px 0 24px;
}
.messages-inner {
  max-width: 760px;
  margin: 0 auto;
  padding: 0 24px;
}

.empty-chat {
  color: var(--muted);
  font-size: 14.5px;
  text-align: center;
  margin: 120px auto 0;
  max-width: 480px;
  line-height: 1.6;
}
.empty-chat-title {
  font-size: 24px;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 10px;
}

.msg {
  margin-bottom: 28px;
  display: flex;
  flex-direction: column;
}

/* USER messages: right-aligned, with a subtle bubble */
.msg.user {
  align-items: flex-end;
}
.msg.user .msg-content {
  background: var(--user-bubble);
  border-radius: 18px;
  padding: 12px 18px;
  max-width: 75%;
  white-space: pre-wrap;
  word-wrap: break-word;
  font-size: 15px;
  color: var(--text);
}

/* ASSISTANT messages: no bubble, full-width prose */
.msg.assistant {
  align-items: stretch;
}
.msg.assistant .msg-content {
  background: transparent;
  padding: 0;
  font-size: 15.5px;
  line-height: 1.7;
  color: var(--text);
}

.msg.assistant .msg-content p { margin: 0 0 1em; }
.msg.assistant .msg-content p:last-child { margin-bottom: 0; }
.msg.assistant .msg-content h1 { font-size: 22px; margin: 1.2em 0 0.4em; font-weight: 600; }
.msg.assistant .msg-content h2 { font-size: 18px; margin: 1.1em 0 0.4em; font-weight: 600; }
.msg.assistant .msg-content h3 { font-size: 16px; margin: 1em 0 0.4em; font-weight: 600; }
.msg.assistant .msg-content ul,
.msg.assistant .msg-content ol { margin: 0 0 1em 1.5em; }
.msg.assistant .msg-content li { margin-bottom: 0.3em; }
.msg.assistant .msg-content code {
  background: var(--code-bg);
  padding: 2px 6px;
  border-radius: 4px;
  font-family: ui-monospace, "JetBrains Mono", Consolas, monospace;
  font-size: 13.5px;
  color: var(--text);
}
.msg.assistant .msg-content pre {
  background: var(--code-block-bg);
  color: var(--code-block-fg);
  padding: 14px 16px;
  border-radius: var(--radius-md);
  overflow-x: auto;
  margin: 1em 0;
  font-size: 13px;
  line-height: 1.55;
}
.msg.assistant .msg-content pre code {
  background: none;
  padding: 0;
  color: inherit;
  font-size: 13px;
}
.msg.assistant .msg-content .md-table-scroll {
  width: 100%;
  overflow-x: auto;
  margin: 1em 0;
  border-radius: var(--radius-md);
}
.msg.assistant .msg-content table {
  border-collapse: collapse;
  margin: 0;
  width: 100%;
  min-width: 480px;
}
.msg.assistant .msg-content th,
.msg.assistant .msg-content td {
  border: 1px solid var(--border);
  padding: 8px 12px;
  text-align: left;
  font-size: 14px;
}
.msg.assistant .msg-content th {
  background: var(--code-bg);
  font-weight: 600;
}
.msg.assistant .msg-content blockquote {
  border-left: 3px solid var(--border-strong);
  padding-left: 16px;
  margin: 1em 0;
  color: var(--text-secondary);
}
.msg.assistant .msg-content .katex-display {
  overflow-x: auto;
  overflow-y: hidden;
  padding: 6px 0;
}
.msg.assistant .msg-content .math-display {
  max-width: 100%;
}
.stream-code-block {
  margin: 1em 0;
  overflow: hidden;
  border-radius: var(--radius-md);
  background: var(--code-block-bg);
  color: var(--code-block-fg);
  box-shadow: 0 0 0 1px rgba(255,255,255,0.08);
}
.stream-code-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 8px 12px;
  background: rgba(255,255,255,0.08);
  color: rgba(255,255,255,0.72);
  font-size: 11px;
  font-family: ui-monospace, "JetBrains Mono", Consolas, monospace;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}
.stream-code-block pre {
  margin: 0;
  padding: 14px 16px;
  overflow-x: auto;
  font-size: 13px;
  line-height: 1.55;
}
.stream-code-block code {
  background: none;
  padding: 0;
  border-radius: 0;
  color: inherit;
  font-family: ui-monospace, "JetBrains Mono", Consolas, monospace;
}

/* Placeholder (Thinking…) */
.placeholder-text {
  font-style: normal;
  color: var(--muted);
  font-size: 14.5px;
  display: flex;
  align-items: center;
  gap: 10px;
}
.spinner {
  display: inline-block;
  width: 14px; height: 14px;
  border: 2.5px solid var(--border);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}
@keyframes spin {
  from { transform: rotate(0deg); }
  to   { transform: rotate(360deg); }
}

/* Meta chips — small and subtle */
.meta-strip {
  margin-top: 10px;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}
.chip {
  display: inline-flex;
  align-items: center;
  height: 22px;
  padding: 0 9px;
  border-radius: var(--radius-pill);
  font-size: 11px;
  font-family: ui-monospace, "JetBrains Mono", Consolas, monospace;
  background: rgba(45,42,38,0.06);
  color: var(--text-secondary);
  border: 1px solid transparent;
}
.chip.pos { background: rgba(79,138,77,0.10); color: var(--pos); }
.chip.neg { background: rgba(181,65,65,0.10); color: var(--neg); }

/* Feedback row */
.feedback-row {
  display: flex;
  align-items: center;
  gap: 2px;
  margin-top: 16px;
  opacity: 0.6;
  transition: opacity 0.15s;
}
.msg.assistant:hover .feedback-row { opacity: 1; }

.fb-btn {
  width: 32px;
  height: 32px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0;
  border-radius: 8px;
  border: none;
  background: transparent;
  cursor: pointer;
  color: var(--text-secondary);
  transition: background 0.12s, color 0.12s;
}
.fb-btn:hover  { background: rgba(45,42,38,0.06); color: var(--text); }
.fb-btn:active { transform: scale(0.94); }

/* Voted state — the chosen thumb stays highlighted, its pair greys out */
.fb-btn.active {
  background: rgba(45,42,38,0.10);
  color: var(--text);
}
.fb-btn:disabled {
  cursor: default;
  opacity: 0.45;
}
.fb-btn:disabled:hover {
  background: transparent;
  border-color: transparent;
  box-shadow: none;
  color: var(--text-secondary);
}
.fb-btn.active:disabled {
  opacity: 1;
  background: rgba(45,42,38,0.10);
  color: var(--text);
}

/* ============================================================
   COMPOSER — rounded, centered, white shell
   ============================================================ */

.composer-wrap {
  flex-shrink: 0;
  padding: 12px 24px 20px;
  background: linear-gradient(180deg, rgba(250,250,247,0) 0%, var(--bg) 60%);
}
.composer {
  max-width: 760px;
  margin: 0 auto;
  background: var(--composer-bg);
  border: 1px solid var(--border-strong);
  border-radius: 22px;
  padding: 10px 14px 10px 18px;
  display: flex;
  align-items: flex-end;
  gap: 8px;
  box-shadow: var(--shadow-sm);
  transition: border-color 0.12s, box-shadow 0.12s;
}
.composer:focus-within {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--accent-soft);
}
.composer textarea {
  flex: 1;
  border: none;
  outline: none;
  resize: none;
  background: transparent;
  font-family: inherit;
  font-size: 15px;
  color: var(--text);
  line-height: 1.55;
  padding: 8px 0;
  max-height: 220px;
  min-height: 24px;
}
.composer textarea::placeholder { color: var(--muted); }

.composer-send {
  width: 34px;
  height: 34px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: 50%;
  cursor: pointer;
  transition: background 0.12s, transform 0.05s;
  flex-shrink: 0;
}
.composer-send:hover  { background: var(--primary-hover); }
.composer-send:active { transform: scale(0.95); }
.composer-send:disabled {
  background: var(--border-strong);
  color: #fff;
  cursor: not-allowed;
}
.composer-send svg { width: 18px; height: 18px; }

.composer-footer {
  max-width: 760px;
  margin: 6px auto 0;
  font-size: 11px;
  color: var(--muted);
  text-align: center;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

/* ============================================================
   Visual polish pass - product UI refresh
   ============================================================ */

.app {
  grid-template-columns: 300px minmax(0, 1fr);
  background:
    linear-gradient(135deg, rgba(200, 122, 76, 0.07), transparent 36%),
    linear-gradient(315deg, rgba(208, 138, 40, 0.07), transparent 32%),
    var(--bg);
}

.sidebar {
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.78), rgba(238, 243, 246, 0.96)),
    var(--sidebar-bg);
  border-right-color: rgba(217, 213, 204, 0.82);
}

.sidebar-header {
  padding: 22px 18px 16px;
  background:
    linear-gradient(180deg, rgba(255,255,255,0.78), rgba(255,255,255,0.2)),
    transparent;
}

.brand-text h1 {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 42px;
  height: 42px;
  border-radius: 10px;
  background: linear-gradient(145deg, var(--primary), #e0975f);
  color: #fff;
  font-size: 17px;
  letter-spacing: 0.02em;
  box-shadow: 0 14px 32px rgba(200, 122, 76, 0.22);
}

.brand-text .brand-sub {
  margin-top: 8px;
  color: var(--sidebar-mut);
  font-size: 12px;
}

.btn-new-chat {
  min-height: 42px;
  border: 1px solid rgba(200, 122, 76, 0.22);
  background: var(--surface);
  color: var(--primary);
  box-shadow: var(--shadow-sm);
}
.btn-new-chat:hover {
  background: var(--primary);
  border-color: var(--primary);
  color: var(--primary-fg);
  box-shadow: var(--shadow-md);
}

.session-empty {
  margin: 8px 8px 14px;
  padding: 14px 12px;
  border: 1px dashed var(--border-strong);
  border-radius: var(--radius-lg);
  color: var(--muted);
  font-size: 12.5px;
  line-height: 1.5;
  background: rgba(255, 255, 255, 0.5);
}

.session-group-title {
  color: var(--sidebar-mut);
  letter-spacing: 0.08em;
}

.session-row {
  border-radius: var(--radius-lg);
}
.session-row:hover {
  background: rgba(255, 255, 255, 0.72);
}
.session-row.active {
  background: var(--surface);
  box-shadow: inset 3px 0 0 var(--primary), 0 1px 2px rgba(45, 42, 38, 0.04);
}
.session-row.active .session-link {
  color: var(--primary);
}

.identity-row {
  background: var(--surface);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
}
.identity-avatar {
  background: linear-gradient(145deg, var(--primary), #e0975f);
  box-shadow: 0 8px 18px rgba(200, 122, 76, 0.18);
}
.sidebar-actions a,
.sidebar-actions button {
  border-radius: var(--radius-md);
}

.chat {
  background:
    linear-gradient(180deg, rgba(255,255,255,0.45), rgba(245,247,251,0) 32%),
    transparent;
}

.chat-header {
  min-height: 70px;
  padding: 14px 34px;
  background: rgba(255, 255, 255, 0.74);
  border-bottom-color: rgba(217, 213, 204, 0.7);
  backdrop-filter: blur(12px);
}
.chat-header h2 {
  font-size: 15px;
  font-weight: 650;
  max-width: 760px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.chat-header-meta {
  display: flex;
  gap: 6px;
  margin-top: 6px;
  flex-wrap: wrap;
}
.chat-header-meta span {
  display: inline-flex;
  align-items: center;
  min-height: 22px;
  padding: 2px 9px;
  border-radius: var(--radius-pill);
  background: var(--secondary);
  color: var(--text-secondary);
  font-size: 11px;
  font-weight: 600;
}

.messages {
  padding: 42px 0 28px;
}
.messages-inner {
  max-width: 840px;
}

.empty-chat {
  margin: 86px auto 0;
  max-width: 780px;
  padding: 0 24px;
  color: var(--text-secondary);
}
.empty-chat-mark {
  width: 56px;
  height: 56px;
  margin: 0 auto 20px;
  display: grid;
  place-items: center;
  border-radius: 14px;
  background: linear-gradient(145deg, var(--primary), #e0975f);
  color: #fff;
  font-size: 24px;
  font-weight: 750;
  box-shadow: 0 18px 44px rgba(200, 122, 76, 0.22);
}
.empty-chat-title {
  font-size: 32px;
  letter-spacing: -0.03em;
  line-height: 1.1;
  margin-bottom: 10px;
}
.empty-chat-sub {
  font-size: 15px;
  margin-bottom: 26px;
}
.prompt-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin-top: 4px;
}
.prompt-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  min-height: 74px;
  padding: 16px 16px 16px 18px;
  border: 1px solid rgba(217, 213, 204, 0.82);
  border-radius: var(--radius-lg);
  background: rgba(255, 255, 255, 0.82);
  color: var(--text);
  text-align: left;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: transform 0.16s ease, border-color 0.16s ease, box-shadow 0.16s ease, background 0.16s ease;
}
.prompt-card:hover {
  transform: translateY(-2px);
  border-color: rgba(200, 122, 76, 0.34);
  box-shadow: var(--shadow-md);
  background: var(--surface);
}
.prompt-card svg {
  width: 20px;
  height: 20px;
  color: var(--primary);
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
  flex: 0 0 auto;
}

.msg {
  margin-bottom: 30px;
}
.msg.user .msg-content {
  background: linear-gradient(180deg, var(--user-bubble), #d8ebe8);
  border: 1px solid rgba(200, 122, 76, 0.12);
  border-radius: 18px 18px 6px 18px;
  box-shadow: 0 8px 18px rgba(200, 122, 76, 0.08);
}
.msg.assistant {
  position: relative;
}
.msg.assistant .msg-content {
  background: rgba(255, 255, 255, 0.64);
  border: 1px solid rgba(223, 231, 238, 0.88);
  border-left: 3px solid rgba(200, 122, 76, 0.34);
  border-radius: var(--radius-lg);
  padding: 18px 20px;
  box-shadow: var(--shadow-sm);
}
.msg.assistant .msg-content .md-table-scroll {
  overflow-x: auto;
  overflow-y: hidden;
  border-radius: var(--radius-md);
  box-shadow: 0 0 0 1px var(--border);
}
.msg.assistant .msg-content th,
.msg.assistant .msg-content td {
  border-color: var(--border);
}
.msg.assistant .msg-content th {
  background: var(--surface-soft);
}
.msg.assistant .msg-content blockquote {
  background: var(--surface-soft);
  border-left-color: var(--primary);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  padding: 12px 16px;
}

.meta-strip {
  margin-top: 12px;
}
.chip {
  background: rgba(255, 255, 255, 0.82);
  border-color: var(--border);
}
.feedback-row {
  margin-top: 12px;
  padding-left: 4px;
}
.fb-btn {
  border: 1px solid transparent;
}
.fb-btn:hover {
  background: var(--surface);
  border-color: var(--border);
  color: var(--primary);
  box-shadow: var(--shadow-sm);
}

.composer-wrap {
  padding: 16px 24px 24px;
  background: linear-gradient(180deg, rgba(245,247,251,0), rgba(245,247,251,0.96) 46%);
}
.composer {
  max-width: 840px;
  border-color: rgba(217, 213, 204, 0.88);
  border-radius: 18px;
  padding: 10px 12px 10px 18px;
  box-shadow: 0 18px 48px rgba(45, 42, 38, 0.1);
}
.composer:focus-within {
  border-color: rgba(200, 122, 76, 0.64);
  box-shadow: 0 0 0 4px rgba(200, 122, 76, 0.1), 0 20px 52px rgba(45, 42, 38, 0.12);
}
.composer-send {
  border-radius: 10px;
  background: linear-gradient(145deg, var(--primary), #e0975f);
  box-shadow: 0 10px 22px rgba(200, 122, 76, 0.22);
}
.composer-send:hover {
  background: linear-gradient(145deg, var(--primary-hover), var(--primary));
}

@media (max-width: 860px) {
  .app {
    grid-template-columns: 1fr;
  }
  .sidebar {
    display: none;
  }
  .chat-header {
    padding: 12px 18px;
  }
  .messages {
    padding-top: 28px;
  }
  .prompt-grid {
    grid-template-columns: 1fr;
  }
  .empty-chat {
    margin-top: 52px;
  }
  .empty-chat-title {
    font-size: 26px;
  }
  .msg.user .msg-content {
    max-width: 88%;
  }
}

/* Streaming: the trailing, not-yet-complete markdown block.
   Kept as plain text so a half-built table/bold never renders then snaps. */
.stream-tail {
  white-space: pre-wrap;
  word-break: break-word;
}