/* ── Ambient background ──────────────────────────────────────────── */
.bg-canvas {
  position: fixed; inset: 0; z-index: 0; overflow: hidden; pointer-events: none;
}
.bg-canvas::before {
  content: '';
  position: absolute; inset: 0;
  background:
    radial-gradient(ellipse 80% 60% at 15% -10%, rgba(147,210,255,0.45) 0%, transparent 65%),
    radial-gradient(ellipse 60% 50% at 85% 105%, rgba(45,212,191,0.28) 0%, transparent 60%),
    radial-gradient(ellipse 50% 40% at 55% 50%,  rgba(186,230,255,0.18) 0%, transparent 60%),
    linear-gradient(175deg, #dbeeff 0%, #edf5ff 45%, #e8f8f5 100%);
}
.orb {
  position: absolute; border-radius: 50%;
  filter: blur(55px); pointer-events: none;
}
.orb-1 {
  width: 480px; height: 380px;
  background: radial-gradient(circle, rgba(99,168,255,0.52) 0%, transparent 68%);
  top: -80px; left: -80px;
  animation: orb1Drift 20s ease-in-out infinite;
}
.orb-2 {
  width: 380px; height: 340px;
  background: radial-gradient(circle, rgba(20,217,196,0.40) 0%, transparent 68%);
  bottom: -60px; right: -60px;
  animation: orb2Drift 26s ease-in-out infinite;
  animation-delay: -8s;
}
.orb-3 {
  width: 280px; height: 280px;
  background: radial-gradient(circle, rgba(147,210,255,0.38) 0%, transparent 68%);
  top: 35%; left: 40%;
  animation: orb3Drift 32s ease-in-out infinite;
  animation-delay: -14s;
}
@keyframes orb1Drift {
  0%   { transform: translate(0, 0) scale(1); }
  25%  { transform: translate(80px, -60px) scale(1.08); }
  55%  { transform: translate(40px, 70px) scale(0.93); }
  80%  { transform: translate(-50px, 30px) scale(1.04); }
  100% { transform: translate(0, 0) scale(1); }
}
@keyframes orb2Drift {
  0%   { transform: translate(0, 0) scale(1); }
  30%  { transform: translate(-70px, -50px) scale(1.07); }
  60%  { transform: translate(-30px, 60px) scale(0.91); }
  85%  { transform: translate(55px, -25px) scale(1.05); }
  100% { transform: translate(0, 0) scale(1); }
}
@keyframes orb3Drift {
  0%   { transform: translate(0, 0) scale(1) rotate(0deg); }
  35%  { transform: translate(60px, -80px) scale(1.12) rotate(8deg); }
  70%  { transform: translate(-55px, 50px) scale(0.88) rotate(-5deg); }
  100% { transform: translate(0, 0) scale(1) rotate(0deg); }
}

/* ── App shell ───────────────────────────────────────────────────── */
#app { position: relative; z-index: 1; display: flex; flex-direction: column; min-height: 100vh; }

/* ── Nav bar ─────────────────────────────────────────────────────── */
.app-nav {
  position: sticky; top: 0; z-index: 200;
  background: rgba(237,245,255,0.82);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  max-width: 1240px; margin: 0 auto;
  display: flex; align-items: center; gap: 0.5rem;
  padding: 0 1.75rem; height: 60px;
}
.logo {
  display: flex; align-items: center; gap: 0.55rem;
  text-decoration: none; flex-shrink: 0; margin-right: 0.75rem;
}
.logo-img {
  height: 40px; width: auto; display: block;
}

.nav-links { display: flex; align-items: center; gap: 0.15rem; flex: 1; }
.nav-link {
  display: inline-flex; align-items: center; gap: 0.4rem;
  padding: 0.38rem 0.8rem; border-radius: var(--r-pill);
  font-weight: 600; font-size: 0.875rem;
  color: var(--text-2); cursor: pointer;
  transition: all 0.15s ease; user-select: none; text-decoration: none;
  border: none; background: none; font-family: var(--font);
}
.nav-link:hover { color: var(--text); background: var(--hover); }
.nav-link.active { color: var(--blue); background: var(--blue-dim); }
.nav-link.soon { color: var(--text-3); cursor: default; pointer-events: none; }
.soon-badge {
  font-size: 0.62rem; font-weight: 700; letter-spacing: 0.04em;
  padding: 0.1rem 0.38rem; border-radius: var(--r-pill);
  background: rgba(99,155,230,0.14); color: var(--text-3);
  text-transform: uppercase;
}

.nav-spacer { flex: 1; }
.nav-actions { display: flex; align-items: center; gap: 0.5rem; }

/* Language toggle — shared across landing pages and app */
.lang-toggle {
  display: flex; align-items: center; gap: 0.25rem;
  background: var(--surface); border: 1px solid var(--border);
  border-radius: 8px; padding: 0.2rem;
}
.lang-btn {
  padding: 0.25rem 0.5rem; border: none; border-radius: 6px;
  background: transparent; color: var(--text-3); cursor: pointer;
  font-family: var(--font); font-weight: 600; font-size: 0.78rem;
  transition: all 0.2s;
}
.lang-btn.active { background: var(--grad); color: #fff; }
.nav-signin {
  font-weight: 600; font-size: 0.875rem; color: var(--text-2);
  cursor: default; padding: 0.38rem 0.8rem; opacity: 0.7;
}

/* ── Nav key button ──────────────────────────────────────────────── */
.nav-key-btn {
  background:none; border:1px solid var(--border-md); border-radius:var(--r);
  padding:0.35rem 0.5rem; cursor:pointer; color:var(--text-2);
  display:flex; align-items:center;
  transition:color 0.15s, background 0.15s, border-color 0.15s;
}
.nav-key-btn:hover { color:var(--blue); background:var(--blue-dim); border-color:var(--border-hi); }

/* ── Sign out button ─────────────────────────────────────────────── */
.nav-signout-btn {
  display: inline-flex; align-items: center; gap: 0.35rem;
  padding: 0.35rem 0.75rem;
  background: transparent; border: 1px solid var(--border-md);
  border-radius: var(--r); color: var(--text-2);
  font-family: var(--font); font-size: 0.8rem; font-weight: 600;
  cursor: pointer;
  transition: all 0.15s ease;
}
.nav-signout-btn:hover { background: var(--blue-dim); color: var(--blue); border-color: var(--border-hi); }
.nav-signout-btn .signout-icon { display: none; }

/* ── Buttons ─────────────────────────────────────────────────────── */
.btn {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 0.55rem 1.15rem;
  border: none; border-radius: var(--r-sm);
  cursor: pointer; font-family: var(--font);
  font-size: 0.875rem; font-weight: 700;
  transition: all 0.16s ease; white-space: nowrap;
  line-height: 1; text-decoration: none;
}
.btn:focus-visible { outline: 2px solid var(--blue); outline-offset: 2px; }
.btn:disabled { opacity: 0.55; cursor: not-allowed; transform: none !important; box-shadow: none !important; }

.btn-primary {
  background: linear-gradient(135deg, #3b82f6 0%, #14d9c4 100%);
  color: #fff;
  box-shadow: 0 2px 12px rgba(59,130,246,0.30);
}
.btn-primary:hover {
  background: linear-gradient(135deg, #5a95f7 0%, #22e4cf 100%);
  box-shadow: 0 4px 20px rgba(59,130,246,0.38);
  transform: translateY(-1px);
}
.btn-primary:active { transform: translateY(0); box-shadow: 0 2px 8px rgba(59,130,246,0.22); }

.btn-ghost {
  background: var(--surface); color: var(--text-2);
  border: 1px solid var(--border-md);
  box-shadow: var(--sh-xs);
}
.btn-ghost:hover { background: #fff; color: var(--text); border-color: var(--border-hi); box-shadow: var(--sh-sm); }

.btn-deep-research {
  font-size: 0.78rem; font-weight: 700;
  background: transparent; color: var(--text-3);
  border: 1.5px solid var(--border-md); border-radius: var(--r);
  padding: 0.38rem 0.72rem; cursor: pointer; transition: all 0.15s;
  white-space: nowrap; flex-shrink: 0;
}
.btn-deep-research:hover { border-color: var(--accent); color: var(--accent); }
.btn-deep-research.active {
  background: var(--accent); color: #fff; border-color: var(--accent);
}
.btn-multilingual {
  font-size: 0.78rem; font-weight: 700;
  background: transparent; color: var(--text-3);
  border: 1.5px solid var(--border-md); border-radius: var(--r);
  padding: 0.38rem 0.72rem; cursor: pointer; transition: all 0.15s;
  white-space: nowrap; flex-shrink: 0;
}
.btn-multilingual:hover { border-color: #059669; color: #059669; }
.btn-multilingual.active { background: #059669; color: #fff; border-color: #059669; }
.btn-conversation {
  font-size: 0.78rem; font-weight: 700;
  background: transparent; color: var(--text-3);
  border: 1.5px solid var(--border-md); border-radius: var(--r);
  padding: 0.38rem 0.72rem; cursor: pointer; transition: all 0.15s;
  white-space: nowrap; flex-shrink: 0;
}
.btn-conversation:hover { border-color: #7c3aed; color: #7c3aed; }
.btn-conversation.active { background: #7c3aed; color: #fff; border-color: #7c3aed; }
.btn-conversation:disabled { opacity: 0.38; cursor: not-allowed; pointer-events: none; }

/* Chat bottom input bar — question-wrap is moved here in conversation mode */
.chat-input-bar {
  border-top: 1px solid var(--border);
  padding: 0.75rem 1rem 0.6rem;
  background: var(--bg);
  flex-shrink: 0;
}
.chat-input-bar .question-wrap {
  /* Override any top-bar-specific sizing so it fills the bottom bar naturally */
  width: 100%;
}

/* Tutorial mode tip cards */
.mode-tips {
  display: flex; gap: 0.75rem; padding: 1rem 1.6rem 0.5rem;
  transition: opacity 0.3s, max-height 0.3s;
  max-height: 200px; overflow: hidden;
}
.mode-tips.hidden { opacity: 0; max-height: 0; pointer-events: none; padding: 0; }
.mode-tip-card {
  flex: 1; display: flex; gap: 0.6rem; align-items: flex-start;
  background: var(--hover); border: 1px solid var(--border);
  border-radius: var(--r); padding: 0.65rem 0.75rem;
}
.mode-tip-icon {
  color: var(--text-3); flex-shrink: 0; margin-top: 1px;
}
.mode-tip-title {
  font-size: 0.78rem; font-weight: 700; color: var(--text); margin-bottom: 0.2rem;
}
.mode-tip-desc {
  font-size: 0.73rem; color: var(--text-2); line-height: 1.4;
}
.mode-tip-cost {
  font-size: 0.68rem; color: var(--text-3); margin-top: 0.25rem;
}

/* Chat panel */
#chat-panel { display: flex; flex-direction: column; flex: 1; overflow: hidden; }
.chat-thread {
  flex: 1; overflow-y: auto; padding: 1rem 1.6rem;
  display: flex; flex-direction: column; gap: 1.5rem;
}
.chat-thread::-webkit-scrollbar { width: 3px; }
.chat-thread::-webkit-scrollbar-thumb { background: var(--border-md); border-radius: 2px; }
.chat-empty {
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  gap: 0.4rem; color: var(--text-3); text-align: center;
  padding: 3rem 1rem; font-size: 0.88rem;
}
.chat-turn { display: flex; flex-direction: column; gap: 0.5rem; }
.chat-turn-question {
  font-size: 0.78rem; font-weight: 600; color: var(--text-2);
  padding: 0.2rem 0.5rem 0.2rem 0;
  border-left: 2px solid var(--accent); padding-left: 0.5rem;
}
.chat-turn-answer {
  font-size: 0.9rem; line-height: 1.65; color: var(--text);
}
.chat-turn-answer.streaming::after {
  content: '▋'; animation: blink 0.7s step-end infinite;
}
.chat-turn-sources { margin-top: 0.5rem; }

/* Conversation turn sources — same source-group structure as RAG panel, under a toggle */
.conv-sources-toggle { margin-top: 0.4rem; }
.conv-sources-header {
  display: flex; align-items: center; gap: 0.4rem;
  font-size: 0.73rem; color: var(--text-3); background: none; border: none;
  cursor: pointer; padding: 0.2rem 0; width: 100%; text-align: left;
  transition: color 0.15s;
}
.conv-sources-header:hover { color: var(--text-2); }
.conv-sources-header .source-group-chevron { margin-left: auto; }
.conv-sources-body { margin-top: 0.35rem; }
.chat-divider {
  border: none; border-top: 1px solid var(--border); margin: 0;
}
.chat-paused-label {
  text-align: center; font-size: 0.72rem; color: var(--text-3);
  padding: 0.3rem 0; font-style: italic;
}
.chat-footer {
  display: flex; align-items: center; justify-content: space-between;
  padding: 0.5rem 1.6rem; border-top: 1px solid var(--border); min-height: 2.2rem;
}
.conv-credits { font-size: 0.72rem; color: var(--text-3); }
.clear-chat-btn {
  font-size: 0.72rem; color: var(--text-3); background: none; border: none;
  cursor: pointer; padding: 0; text-decoration: underline;
  text-underline-offset: 2px;
}
.clear-chat-btn:hover { color: var(--text-2); }

.deep-research-progress {
  padding: 0.6rem 0.9rem; border-radius: var(--r);
  background: var(--hover); border: 1px solid var(--border);
  margin-bottom: 0.75rem; display: none;
}
.deep-research-progress.visible { display: block; }
.deep-sub-item {
  display: flex; align-items: flex-start; gap: 0.5rem;
  font-size: 0.8rem; color: var(--text-2); padding: 0.18rem 0;
}
.deep-sub-spinner {
  flex-shrink: 0; width: 14px; text-align: center;
  animation: pulse 1s ease-in-out infinite; color: var(--accent);
}
.deep-sub-spinner.done { animation: none; color: #22c55e; }

.btn-danger {
  background: var(--red-dim); color: var(--red);
  border: 1px solid rgba(239,68,68,0.18);
}
.btn-danger:hover { background: rgba(239,68,68,0.15); }

.btn-icon {
  padding: 0.3rem 0.4rem; background: transparent; color: var(--text-3);
  border-radius: var(--r-sm); line-height: 1; border: none;
}
.btn-icon:hover { background: var(--hover); color: var(--text-2); }

.btn-sm { padding: 0.35rem 0.72rem; font-size: 0.8rem; }

/* ── Views ───────────────────────────────────────────────────────── */
.view { display: none; }
.view.active { display: block; animation: viewIn 0.22s ease both; }
#detail.active { display: flex; flex-direction: column; }
@keyframes viewIn {
  from { opacity: 0; transform: translateY(10px); }
  to   { opacity: 1; transform: translateY(0); }
}