:root {
  --bg: #f5f7fb;
  --panel: #ffffff;
  --panel-2: #f0f3f9;
  --text: #111827;
  --muted: #6b7280;
  --line: #e5e7eb;
  --shadow: 0 18px 50px rgba(15, 23, 42, 0.08);
  --blue: #2563eb;
  --blue-2: #1d4ed8;
  --chip: #eef2ff;
  --chip-text: #3730a3;
  --good: #16a34a;
  --warn: #f59e0b;
  --danger: #dc2626;
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Arial, "Apple Color Emoji", "Segoe UI Emoji";
  color: var(--text);
  background: radial-gradient(1200px 600px at 15% 0%, rgba(37,99,235,0.12), transparent 55%),
              radial-gradient(900px 520px at 100% 20%, rgba(245,158,11,0.08), transparent 55%),
              var(--bg);
}

.app {
  height: 100%;
  display: grid;
  grid-template-columns: 280px 1fr 320px;
  gap: 16px;
  padding: 20px;
}

.sidebar, .main, .rightbar {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 18px;
  box-shadow: var(--shadow);
  overflow: hidden;
}

.sidebar { display: flex; flex-direction: column; }
.brand {
  display: flex;
  gap: 12px;
  align-items: center;
  padding: 16px 16px 8px 16px;
}
.logo {
  width: 40px; height: 40px;
  display: grid; place-items: center;
  background: #111827;
  color: #fff;
  border-radius: 12px;
  font-size: 18px;
}
.brand .name { font-weight: 800; }
.brand .sub { color: var(--muted); font-size: 12px; margin-top: 1px; }

.search { padding: 8px 16px 12px 16px; }
.search input {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 10px 12px;
  outline: none;
  background: var(--panel-2);
}

.nav {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 0 10px 10px 10px;
}
.nav-item {
  text-align: left;
  width: 100%;
  border: 1px solid transparent;
  background: transparent;
  padding: 10px 12px;
  border-radius: 12px;
  color: var(--text);
  cursor: pointer;
  font-weight: 600;
}
.nav-item:hover { background: var(--panel-2); }
.nav-item.active {
  background: #eef2ff;
  border-color: #e0e7ff;
  color: #1e3a8a;
}
.nav-item.subtle { color: var(--muted); font-weight: 600; }
.spacer { flex: 1; }

.sidebar-footer {
  padding: 14px 16px 16px 16px;
  border-top: 1px solid var(--line);
  background: linear-gradient(180deg, transparent, rgba(15,23,42,0.02));
}
.toggle { display: flex; gap: 8px; }
.chip {
  border: 1px solid var(--line);
  background: var(--panel-2);
  padding: 7px 10px;
  border-radius: 999px;
  cursor: pointer;
  font-weight: 700;
  font-size: 12px;
  color: var(--muted);
}
.chip.active { background: var(--chip); color: var(--chip-text); border-color: #e0e7ff; }
.user { display: flex; gap: 10px; align-items: center; margin-top: 12px; }
.avatar {
  width: 36px; height: 36px; border-radius: 12px;
  background: #eef2ff; color: #1e3a8a;
  display: grid; place-items: center;
  font-weight: 900;
}
.user-name { font-weight: 800; font-size: 13px; }
.user-sub { color: var(--muted); font-size: 12px; }

.main { display: flex; flex-direction: column; min-width: 0; }
.topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 14px 16px;
  border-bottom: 1px solid var(--line);
}
.topbar .title { font-weight: 900; }
.topbar .actions { display: flex; gap: 8px; }

.content { display: flex; flex-direction: column; height: 100%; min-height: 0; }

.banner {
  margin: 12px 16px 0 16px;
  padding: 10px 12px;
  border-radius: 14px;
  border: 1px solid #fee2e2;
  background: #fff1f2;
  color: #991b1b;
  font-weight: 700;
  font-size: 13px;
}
.banner code { font-weight: 900; }

.welcome {
  padding: 28px 20px 10px 20px;
  text-align: center;
}
.welcome h1 { margin: 0; font-size: 34px; letter-spacing: -0.02em; }
.welcome p { margin: 8px 0 18px 0; color: var(--muted); }
.tiles {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  max-width: 740px;
  margin: 0 auto;
}
.tile {
  text-align: left;
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 16px;
  padding: 14px 14px;
  cursor: pointer;
}
.tile:hover { background: var(--panel-2); }
.tile-title { font-weight: 900; }
.tile-sub { color: var(--muted); font-size: 12px; margin-top: 4px; }

.chat {
  flex: 1;
  padding: 10px 16px 0 16px;
  overflow: auto;
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.msg {
  max-width: 92%;
  border-radius: 16px;
  padding: 12px 12px;
  border: 1px solid var(--line);
  background: #fff;
  white-space: pre-wrap;
  line-height: 1.35;
  font-size: 14px;
}
.msg.user { margin-left: auto; background: #eef2ff; border-color: #e0e7ff; }
.msg.assistant { margin-right: auto; }
.msg .meta { font-size: 11px; color: var(--muted); margin-bottom: 6px; }
.msg .badge {
  display: inline-flex;
  gap: 6px;
  align-items: center;
  padding: 2px 8px;
  border-radius: 999px;
  font-weight: 800;
  font-size: 11px;
  border: 1px solid var(--line);
  background: #fff;
}
.badge.good { color: var(--good); }
.badge.warn { color: var(--warn); }

.composer {
  padding: 12px 16px 16px 16px;
  border-top: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(15,23,42,0.02), transparent);
}
.composer-inner {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 10px;
  align-items: end;
}
textarea {
  width: 100%;
  resize: none;
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 12px 12px;
  outline: none;
  background: #fff;
  min-height: 48px;
  max-height: 160px;
  font-family: inherit;
  font-size: 14px;
}
.btn {
  border: 1px solid var(--line);
  background: #fff;
  color: var(--text);
  padding: 10px 12px;
  border-radius: 14px;
  cursor: pointer;
  font-weight: 800;
}
.btn.small { padding: 8px 10px; border-radius: 12px; font-size: 12px; }
.btn.primary {
  background: var(--blue);
  border-color: var(--blue);
  color: #fff;
}
.btn.primary:hover { background: var(--blue-2); border-color: var(--blue-2); }
.btn.ghost { background: transparent; }
.btn.ghost:hover { background: var(--panel-2); }

.composer-hint {
  margin-top: 8px;
  font-size: 12px;
  color: var(--muted);
}
.composer-hint code { color: #111827; }

.rightbar {
  display: flex;
  flex-direction: column;
}
.right-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 14px 16px;
  border-bottom: 1px solid var(--line);
}
.right-title { font-weight: 900; }
.right-list {
  padding: 10px 10px 16px 10px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.project {
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 12px 12px;
  cursor: pointer;
  background: #fff;
}
.project:hover { background: var(--panel-2); }
.project.active { background: #f8fafc; border-color: #dbeafe; }
.project-title { font-weight: 900; }
.project-sub { color: var(--muted); font-size: 12px; margin-top: 4px; }

.modal {
  position: fixed;
  inset: 0;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 20px;
  z-index: 50;
}
.modal.open { display: flex; }
.modal-overlay {
  position: absolute;
  inset: 0;
  background: rgba(15, 23, 42, 0.45);
}
.modal-card {
  position: relative;
  width: min(560px, 92vw);
  border-radius: 18px;
  background: var(--panel);
  border: 1px solid var(--line);
  box-shadow: 0 30px 90px rgba(0,0,0,0.30);
  padding: 14px;
}
.modal-head {
  display: flex;
  align-items: start;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 10px;
}
.modal-title { font-weight: 950; font-size: 16px; }
.modal-sub { color: var(--muted); font-size: 12px; margin-top: 2px; }
.modal-label { display: block; font-weight: 800; font-size: 12px; margin-top: 10px; }
.modal-input {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 10px 12px;
  margin-top: 6px;
  outline: none;
  background: var(--panel-2);
}
.modal-help { color: var(--muted); font-size: 12px; margin-top: 8px; line-height: 1.35; }
.modal-help code { color: var(--text); font-weight: 900; }
.modal-actions {
  display: flex;
  justify-content: flex-end;
  gap: 10px;
  margin-top: 14px;
}

@media (max-width: 1100px) {
  .app { grid-template-columns: 260px 1fr; }
  .rightbar { display: none; }
}
@media (max-width: 820px) {
  .app { grid-template-columns: 1fr; }
  .sidebar { display: none; }
  .tiles { grid-template-columns: 1fr; }
}

body[data-theme="dark"] {
  --bg: #0b1220;
  --panel: #0f172a;
  --panel-2: #111c33;
  --text: #e5e7eb;
  --muted: #94a3b8;
  --line: rgba(148, 163, 184, 0.22);
  --shadow: 0 18px 50px rgba(0, 0, 0, 0.35);
  --chip: rgba(37, 99, 235, 0.15);
  --chip-text: #c7d2fe;
}
body[data-theme="dark"] .logo { background: #111827; }
body[data-theme="dark"] .msg.assistant { background: rgba(255,255,255,0.03); }
body[data-theme="dark"] .tile { background: rgba(255,255,255,0.03); }
body[data-theme="dark"] textarea { background: rgba(255,255,255,0.02); }
body[data-theme="dark"] .banner { background: rgba(220, 38, 38, 0.12); border-color: rgba(220, 38, 38, 0.35); color: #fecaca; }