:root {
  color-scheme: light;
  --chat-bg: oklch(97.2% 0.008 248);
  --chat-surface: oklch(99.5% 0.003 248);
  --chat-surface-muted: oklch(95.5% 0.014 248);
  --chat-border: oklch(87.8% 0.018 248);
  --chat-ink: oklch(25% 0.045 252);
  --chat-ink-soft: oklch(42% 0.035 252);
  --chat-muted: oklch(49% 0.026 252);
  --chat-navy: oklch(32% 0.105 252);
  --chat-navy-hover: oklch(27% 0.105 252);
  --chat-teal: oklch(50% 0.095 178);
  --chat-teal-soft: oklch(94% 0.035 178);
  --chat-blue-soft: oklch(94.5% 0.033 248);
  --chat-danger: oklch(48% 0.17 25);
  --chat-danger-soft: oklch(96% 0.025 25);
  --chat-warning: oklch(52% 0.12 75);
  --chat-warning-soft: oklch(96% 0.035 75);
  --chat-radius: 14px;
  --chat-control: 10px;
  --chat-ease: 180ms cubic-bezier(.22, 1, .36, 1);
}

html, body { min-width: 320px; height: 100%; background: var(--chat-bg); }
body, body.light-mode { color: var(--chat-ink); background: var(--chat-bg); overflow: hidden; }
.hidden { display: none !important; }
.skip-link { position: fixed; top: 10px; left: 10px; z-index: 300; padding: 9px 12px; border-radius: 8px; color: white; background: var(--chat-navy); transform: translateY(-160%); transition: transform var(--chat-ease); }
.skip-link:focus { transform: translateY(0); }

.shell { height: 100%; min-height: 0; }
.shell-sidebar,
body.light-mode .shell-sidebar {
  color: var(--chat-ink-soft);
  background: var(--chat-surface);
  border-color: var(--chat-border);
  box-shadow: none;
}
body.light-mode .shell-sidebar * { color: inherit; }
.sidebar-brand { min-height: 64px; padding: 12px 18px; border-color: var(--chat-border); }
.sidebar-brand .brand-logo { width: 36px; height: 36px; border-radius: 10px; background: var(--chat-navy); }
.sidebar-brand .brand-logo img { width: 28px; height: 28px; }
.sidebar-brand .brand-name,
body.light-mode .sidebar-brand .brand-name { color: var(--chat-navy); background: none; -webkit-text-fill-color: currentColor; font-size: 16px; letter-spacing: 0; }
.nav-section-title { color: var(--chat-muted); letter-spacing: .04em; text-transform: none; }
.nav-item { color: var(--chat-ink-soft); }
.nav-item:hover { color: var(--chat-navy); background: var(--chat-surface-muted); }
.nav-item.active { color: var(--chat-navy); background: var(--chat-blue-soft); border: 0; box-shadow: none; }
.nav-item.active::before { display: none; }
.sidebar-footer { color: var(--chat-muted); border-color: var(--chat-border); }
.sidebar-footer a { color: var(--chat-muted); }
.sidebar-footer a:hover { color: var(--chat-navy); }

.shell-main { height: 100%; min-height: 0; background: var(--chat-bg); }
.shell-topbar,
body.light-mode .shell-topbar {
  min-height: 58px;
  height: 58px;
  color: var(--chat-ink);
  background: color-mix(in oklch, var(--chat-bg), white 40%);
  border-color: var(--chat-border);
  box-shadow: none;
  backdrop-filter: none;
}
.topbar-left { max-width: none; }
.chat-page-title { display: flex; align-items: center; gap: 10px; min-width: 0; }
.chat-page-title strong { color: var(--chat-navy); font-size: 15px; }
.chat-page-title span { color: var(--chat-muted); font-size: 12px; }
.topbar-right { min-width: 0; }
.topbar-btn { color: var(--chat-muted); background: transparent; }
.topbar-btn:hover { color: var(--chat-navy); background: var(--chat-blue-soft); }
.user-avatar { color: white; background: var(--chat-navy); }
.user-name { color: var(--chat-ink-soft); }
.user-role { color: var(--chat-teal); background: var(--chat-teal-soft); }
.sh-btn-pri { color: white; background: var(--chat-navy); }
.sh-btn-pri:hover { background: var(--chat-navy-hover); }
.mobile-toggle { color: var(--chat-ink-soft); background: transparent; }

.shell-content { flex: 1; min-height: 0; padding: 0 !important; margin: 0 !important; max-width: none !important; }
.chat-panel { height: 100%; min-height: 0; display: flex; flex-direction: column; }
.chat-toolbar { min-height: 52px; flex: 0 0 auto; display: flex; align-items: center; justify-content: space-between; gap: 16px; padding: 0 24px; border-bottom: 1px solid var(--chat-border); background: var(--chat-bg); }
.model-status { display: inline-flex; align-items: center; gap: 8px; color: var(--chat-ink-soft); font-size: 12px; font-weight: 700; }
.model-status::before { content: ""; width: 7px; height: 7px; border-radius: 50%; background: var(--chat-teal); }
.toolbar-actions { display: flex; gap: 6px; }
.tool-button { min-height: 34px; display: inline-flex; align-items: center; justify-content: center; gap: 6px; padding: 0 10px; border: 1px solid var(--chat-border); border-radius: 8px; color: var(--chat-ink-soft); background: var(--chat-surface); cursor: pointer; font-size: 12px; font-weight: 700; transition: color var(--chat-ease), border-color var(--chat-ease), background var(--chat-ease); }
.tool-button:hover { color: var(--chat-navy); border-color: var(--chat-navy); background: var(--chat-blue-soft); }

.chat-scroll { flex: 1; min-height: 0; overflow-y: auto; scroll-behavior: smooth; }
.chat-inner { width: min(860px, calc(100% - 40px)); min-height: 100%; margin: 0 auto; padding: 28px 0 34px; display: flex; flex-direction: column; gap: 18px; }
.welcome-state { flex: 1; display: flex; flex-direction: column; justify-content: center; padding: 22px 0 46px; }
.welcome-state h1 { max-width: 18ch; margin: 0; color: var(--chat-navy); font-size: 32px; line-height: 1.22; letter-spacing: -.025em; text-wrap: balance; }
.welcome-state > p { max-width: 62ch; margin: 12px 0 0; color: var(--chat-ink-soft); font-size: 14px; line-height: 1.7; text-wrap: pretty; }
.suggestion-list { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; margin-top: 26px; }
.suggestion { min-height: 74px; padding: 14px; border: 1px solid var(--chat-border); border-radius: 12px; color: var(--chat-ink); background: var(--chat-surface); cursor: pointer; text-align: left; transition: color var(--chat-ease), border-color var(--chat-ease), background var(--chat-ease); }
.suggestion:hover { color: var(--chat-navy); border-color: color-mix(in oklch, var(--chat-navy), white 48%); background: var(--chat-blue-soft); }
.suggestion strong { display: block; font-size: 13px; }
.suggestion span { display: block; margin-top: 4px; color: var(--chat-muted); font-size: 12px; line-height: 1.5; }

.message { max-width: min(88%, 720px); display: flex; align-items: start; gap: 10px; }
.message.user { align-self: flex-end; flex-direction: row-reverse; }
.message.ai { align-self: flex-start; }
.message-avatar { width: 34px; height: 34px; flex: 0 0 auto; display: grid; place-items: center; border-radius: 10px; color: white; background: var(--chat-teal); font-size: 11px; font-weight: 800; }
.message.user .message-avatar { background: var(--chat-navy); }
.message-body { min-width: 0; display: flex; flex-direction: column; gap: 5px; }
.message.user .message-body { align-items: flex-end; }
.message-bubble { padding: 12px 14px; border-radius: 12px; color: var(--chat-ink-soft); background: var(--chat-surface); font-size: 14px; line-height: 1.72; white-space: pre-wrap; overflow-wrap: anywhere; }
.message.user .message-bubble { color: var(--chat-navy); background: var(--chat-blue-soft); }
.message-actions { min-height: 28px; opacity: 0; transition: opacity var(--chat-ease); }
.message:hover .message-actions, .message:focus-within .message-actions { opacity: 1; }
.copy-message { min-height: 28px; padding: 0 8px; border: 0; border-radius: 6px; color: var(--chat-muted); background: transparent; cursor: pointer; font-size: 11px; }
.copy-message:hover { color: var(--chat-navy); background: var(--chat-surface-muted); }

.typing { min-width: 44px; min-height: 22px; display: flex; align-items: center; gap: 5px; }
.typing span { width: 6px; height: 6px; border-radius: 50%; background: var(--chat-teal); animation: chat-typing 1.2s ease-in-out infinite; }
.typing span:nth-child(2) { animation-delay: 120ms; }
.typing span:nth-child(3) { animation-delay: 240ms; }
@keyframes chat-typing { 50% { opacity: .35; transform: translateY(-2px); } }

.chat-notice { display: none; align-items: start; gap: 10px; margin-bottom: 8px; padding: 12px 13px; border-radius: var(--chat-control); color: var(--chat-ink-soft); background: var(--chat-surface-muted); }
.chat-notice.visible { display: flex; }
.chat-notice.error { color: var(--chat-danger); background: var(--chat-danger-soft); }
.chat-notice.warning { color: var(--chat-warning); background: var(--chat-warning-soft); }
.notice-icon { width: 20px; height: 20px; flex: 0 0 auto; display: grid; place-items: center; border-radius: 50%; color: white; background: currentColor; font-size: 11px; font-weight: 800; }
.notice-copy { flex: 1; min-width: 0; }
.notice-copy strong { display: block; color: currentColor; font-size: 12px; }
.notice-copy p { margin: 3px 0 0; color: var(--chat-ink-soft); font-size: 12px; line-height: 1.5; }
.notice-actions { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 8px; }
.notice-action { min-height: 32px; display: inline-flex; align-items: center; padding: 0 10px; border: 1px solid var(--chat-border); border-radius: 8px; color: var(--chat-navy); background: white; cursor: pointer; font-size: 12px; font-weight: 700; text-decoration: none; }

.composer-area { flex: 0 0 auto; padding: 10px 24px 14px; background: linear-gradient(to bottom, transparent, var(--chat-bg) 18%); }
.composer-wrap { width: min(860px, 100%); margin: 0 auto; }
.composer { display: flex; align-items: end; gap: 8px; padding: 7px; border: 1px solid var(--chat-border); border-radius: 12px; background: var(--chat-surface); transition: border-color var(--chat-ease), box-shadow var(--chat-ease); }
.composer:focus-within { border-color: var(--chat-navy); box-shadow: 0 0 0 3px color-mix(in oklch, var(--chat-navy), transparent 82%); }
.composer textarea { flex: 1; min-height: 42px; max-height: 132px; padding: 10px 8px; border: 0; outline: none; resize: none; color: var(--chat-ink); background: transparent; font-size: 14px; line-height: 1.55; }
.composer textarea::placeholder { color: oklch(48% 0.026 252); opacity: 1; }
.send-button { min-width: 68px; min-height: 42px; flex: 0 0 auto; border: 1px solid var(--chat-navy); border-radius: 9px; color: white; background: var(--chat-navy); cursor: pointer; font-size: 13px; font-weight: 750; transition: background var(--chat-ease); }
.send-button:hover { background: var(--chat-navy-hover); }
.send-button:disabled { border-color: var(--chat-border); color: var(--chat-muted); background: var(--chat-surface-muted); cursor: wait; }
.composer-meta { display: flex; justify-content: space-between; gap: 12px; margin-top: 6px; padding: 0 3px; color: var(--chat-muted); font-size: 11px; }

.confirm-dialog { width: min(390px, calc(100% - 32px)); padding: 24px; border: 0; border-radius: 14px; color: var(--chat-ink); background: var(--chat-surface); }
.confirm-dialog::backdrop { background: color-mix(in oklch, var(--chat-navy), transparent 66%); }
.confirm-dialog h2 { margin: 0; color: var(--chat-navy); font-size: 18px; }
.confirm-dialog p { margin: 8px 0 20px; color: var(--chat-ink-soft); font-size: 13px; line-height: 1.6; }
.dialog-actions { display: flex; justify-content: flex-end; gap: 8px; }
.dialog-button { min-height: 38px; padding: 0 14px; border-radius: 9px; cursor: pointer; font-size: 13px; font-weight: 700; }
.dialog-cancel { border: 1px solid var(--chat-border); color: var(--chat-ink-soft); background: white; }
.dialog-confirm { border: 1px solid var(--chat-danger); color: white; background: var(--chat-danger); }

.shell-footer { display: none; }
:focus-visible { outline: 3px solid color-mix(in oklch, var(--chat-teal), transparent 52%); outline-offset: 2px; }

@media (max-width: 768px) {
  .shell-sidebar.open { box-shadow: 12px 0 28px color-mix(in oklch, var(--chat-navy), transparent 76%); }
  .shell-topbar { padding: 0 12px; }
  .chat-page-title span, .user-name, .user-role { display: none; }
  .chat-toolbar { padding: 0 14px; }
  .tool-button span { display: none; }
  .chat-inner { width: calc(100% - 28px); padding: 20px 0 26px; }
  .welcome-state { justify-content: start; padding-top: 22px; }
  .welcome-state h1 { font-size: 27px; }
  .suggestion-list { grid-template-columns: 1fr; }
  .message { max-width: 94%; }
  .composer-area { padding: 8px 14px max(12px, env(safe-area-inset-bottom)); }
  .composer-meta span:first-child { display: none; }
}

@media (max-width: 420px) {
  .chat-toolbar { min-height: 48px; }
  .model-status { font-size: 11px; }
  .send-button { min-width: 60px; padding: 0 10px; }
  .message-avatar { width: 30px; height: 30px; border-radius: 8px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
}