/* ── Variables ─────────────────────────────────────────────────────────────── */
:root {
  --bg:          #0d1117;
  --bg2:         #161b22;
  --bg3:         #1c2128;
  --border:      #30363d;
  --text:        #e6edf3;
  --text2:       #8b949e;
  --text3:       #6e7681;
  --accent:      #00e5ff;
  --accent-dim:  #00b3cc;
  --accent-glow: rgba(0, 229, 255, 0.12);
  --green:       #3fb950;
  --red:         #f85149;
  --yellow:      #d29922;
  --blue:        #388bfd;
  --mono:        'JetBrains Mono', 'Cascadia Code', 'Fira Code', monospace;
  --sans:        'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --r:           8px;
  --r-lg:        12px;
  --shadow:      0 4px 24px rgba(0,0,0,0.4);
}

/* ── Reset ─────────────────────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--sans);
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  font-size: 15px;
  line-height: 1.6;
}
a { color: var(--accent); text-decoration: none; }
a:hover { color: var(--accent-dim); }
img { max-width: 100%; }

/* ── Typography ─────────────────────────────────────────────────────────────── */
h1, h2, h3, h4 { font-weight: 600; line-height: 1.3; color: var(--text); }
h1 { font-size: 2.2rem; }
h2 { font-size: 1.6rem; }
h3 { font-size: 1.2rem; }
p  { color: var(--text2); }
code, .mono { font-family: var(--mono); font-size: 0.85em; }

/* ── Navbar ─────────────────────────────────────────────────────────────────── */
.navbar {
  position: sticky; top: 0; z-index: 100;
  background: rgba(13, 17, 23, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}
.nav-container {
  max-width: 1200px; margin: 0 auto;
  padding: 0 1.5rem;
  display: flex; align-items: center; justify-content: space-between;
  height: 56px;
}
.nav-brand {
  display: flex; align-items: center; gap: 0.4rem;
  font-size: 1.15rem; font-weight: 700; color: var(--text);
  letter-spacing: -0.02em;
}
.brand-icon {
  font-family: var(--mono);
  color: var(--accent);
  font-size: 1.2rem;
}
.brand-accent { color: var(--accent); }
.nav-links {
  display: flex; align-items: center; gap: 1.2rem;
}
.nav-link {
  color: var(--text2); font-size: 0.9rem; font-weight: 500;
  transition: color .2s;
}
.nav-link:hover { color: var(--text); }
.nav-user {
  font-size: 0.85rem; color: var(--text3);
  font-family: var(--mono);
  border: 1px solid var(--border);
  padding: 3px 10px; border-radius: 20px;
}

/* ── Buttons ─────────────────────────────────────────────────────────────────── */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 0.4rem;
  border: none; border-radius: var(--r); cursor: pointer;
  font-family: var(--sans); font-weight: 500; transition: all .2s;
  text-decoration: none; white-space: nowrap;
}
.btn:disabled { opacity: 0.45; cursor: not-allowed; }
.btn-primary {
  background: var(--accent); color: #000; padding: 0.55rem 1.2rem; font-size: 0.9rem;
}
.btn-primary:hover:not(:disabled) { background: var(--accent-dim); color: #000; }
.btn-outline {
  background: transparent; border: 1px solid var(--border);
  color: var(--text2); padding: 0.5rem 1.1rem; font-size: 0.9rem;
}
.btn-outline:hover:not(:disabled) { border-color: var(--accent); color: var(--accent); }
.btn-ghost {
  background: transparent; color: var(--text2); padding: 0.5rem 1rem;
}
.btn-ghost:hover { color: var(--text); background: var(--bg3); }
.btn-danger {
  background: var(--red); color: #fff; padding: 0.55rem 1.2rem; font-size: 0.9rem;
}
.btn-sm { padding: 0.35rem 0.85rem !important; font-size: 0.82rem !important; }
.btn-lg { padding: 0.75rem 1.8rem !important; font-size: 1rem !important; }
.btn-full { width: 100%; }
.btn-icon { width: 36px; height: 36px; padding: 0; border-radius: var(--r); font-size: 1rem; }

/* ── Flash messages ──────────────────────────────────────────────────────────── */
.flash-container {
  position: fixed; top: 64px; right: 1rem; z-index: 200;
  display: flex; flex-direction: column; gap: 0.5rem; max-width: 380px;
}
.flash {
  display: flex; align-items: center; justify-content: space-between; gap: 1rem;
  padding: 0.75rem 1rem; border-radius: var(--r);
  font-size: 0.875rem; font-weight: 500; box-shadow: var(--shadow);
  animation: slideIn .25s ease;
}
@keyframes slideIn { from { transform: translateX(120%); opacity: 0; } to { transform: none; opacity: 1; } }
.flash-success { background: #1a2e1f; border: 1px solid var(--green); color: var(--green); }
.flash-error   { background: #2e1a1a; border: 1px solid var(--red);   color: var(--red);   }
.flash-warning { background: #2e261a; border: 1px solid var(--yellow); color: var(--yellow);}
.flash-info    { background: #1a2030; border: 1px solid var(--blue);   color: var(--blue);  }
.flash-close { background: none; border: none; cursor: pointer; color: inherit; font-size: 1.1rem; line-height: 1; }

/* ── Cards ────────────────────────────────────────────────────────────────────── */
.card {
  background: var(--bg2); border: 1px solid var(--border);
  border-radius: var(--r-lg); padding: 1.5rem;
  transition: border-color .2s, box-shadow .2s;
}
.card:hover { border-color: #444; box-shadow: 0 0 20px rgba(0,229,255,0.06); }
.card-glow { border-color: var(--accent); box-shadow: 0 0 0 1px var(--accent-glow); }

/* ── Badges ────────────────────────────────────────────────────────────────────── */
.badge {
  display: inline-flex; align-items: center; gap: 0.3rem;
  padding: 3px 10px; border-radius: 20px; font-size: 0.75rem; font-weight: 600;
  text-transform: uppercase; letter-spacing: 0.04em;
}
.badge-easy   { background: rgba(63,185,80,0.15);  color: var(--green);  border: 1px solid rgba(63,185,80,0.3); }
.badge-medium { background: rgba(210,153,34,0.15); color: var(--yellow); border: 1px solid rgba(210,153,34,0.3); }
.badge-hard   { background: rgba(248,81,73,0.15);  color: var(--red);    border: 1px solid rgba(248,81,73,0.3); }
.badge-cat    { background: rgba(0,229,255,0.1);   color: var(--accent); border: 1px solid rgba(0,229,255,0.2); }
.badge-points { background: rgba(56,139,253,0.15); color: var(--blue);   border: 1px solid rgba(56,139,253,0.3); }

/* ── Forms ────────────────────────────────────────────────────────────────────── */
.form-group { display: flex; flex-direction: column; gap: 0.4rem; }
.form-label { font-size: 0.85rem; font-weight: 500; color: var(--text2); }
.form-control {
  background: var(--bg3); border: 1px solid var(--border);
  color: var(--text); border-radius: var(--r);
  padding: 0.65rem 0.9rem; font-size: 0.9rem; font-family: var(--sans);
  width: 100%; transition: border-color .2s, box-shadow .2s;
  outline: none;
}
.form-control:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-glow);
}
.form-control::placeholder { color: var(--text3); }
.form-hint { font-size: 0.78rem; color: var(--text3); }

/* ── Layout helpers ────────────────────────────────────────────────────────────── */
.container { max-width: 1200px; margin: 0 auto; padding: 0 1.5rem; }
.container-sm { max-width: 480px; margin: 0 auto; padding: 0 1.5rem; }
main { flex: 1; }
.section { padding: 4rem 0; }
.section-sm { padding: 2rem 0; }
.divider { border: none; border-top: 1px solid var(--border); margin: 1.5rem 0; }
.text-center { text-align: center; }
.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-1 { gap: 0.5rem; }
.gap-2 { gap: 1rem; }
.gap-3 { gap: 1.5rem; }
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mb-2 { margin-bottom: 1rem; }
.w-full { width: 100%; }

/* ── Hero ──────────────────────────────────────────────────────────────────────── */
.hero {
  padding: 6rem 0 5rem;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute; inset: 0;
  background: radial-gradient(ellipse 80% 50% at 50% -10%, rgba(0,229,255,0.08) 0%, transparent 70%);
  pointer-events: none;
}
.hero-label {
  display: inline-block;
  font-family: var(--mono); font-size: 0.78rem;
  color: var(--accent); border: 1px solid rgba(0,229,255,0.3);
  padding: 4px 14px; border-radius: 20px; margin-bottom: 1.5rem;
  letter-spacing: 0.08em;
}
.hero h1 { font-size: clamp(2rem, 5vw, 3.2rem); margin-bottom: 1.2rem; }
.hero h1 span { color: var(--accent); }
.hero p { max-width: 560px; margin: 0 auto 2.5rem; font-size: 1.05rem; color: var(--text2); }
.hero-actions { display: flex; gap: 1rem; justify-content: center; flex-wrap: wrap; }
.hero-stats {
  display: flex; justify-content: center; gap: 3rem;
  margin-top: 4rem; flex-wrap: wrap;
}
.hero-stat { text-align: center; }
.hero-stat .stat-num {
  font-size: 2rem; font-weight: 700; font-family: var(--mono);
  color: var(--accent); display: block;
}
.hero-stat .stat-label { font-size: 0.82rem; color: var(--text3); }

/* ── Features grid ─────────────────────────────────────────────────────────────── */
.features-grid {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem; margin-top: 3rem;
}
.feature-card {
  background: var(--bg2); border: 1px solid var(--border);
  border-radius: var(--r-lg); padding: 1.8rem;
}
.feature-icon {
  width: 44px; height: 44px;
  background: var(--accent-glow); border-radius: var(--r);
  display: flex; align-items: center; justify-content: center;
  font-size: 1.3rem; margin-bottom: 1rem;
  border: 1px solid rgba(0,229,255,0.2);
}
.feature-card h3 { font-size: 1rem; margin-bottom: 0.5rem; }
.feature-card p  { font-size: 0.875rem; }

/* ── Dashboard ─────────────────────────────────────────────────────────────────── */
.dashboard-header {
  padding: 2.5rem 0 1rem;
  border-bottom: 1px solid var(--border);
  margin-bottom: 2rem;
}
.stats-row {
  display: flex; gap: 1rem; flex-wrap: wrap; margin-bottom: 2rem;
}
.stat-card {
  background: var(--bg2); border: 1px solid var(--border); border-radius: var(--r);
  padding: 1rem 1.4rem; min-width: 140px;
}
.stat-card .stat-value {
  font-size: 1.8rem; font-weight: 700; font-family: var(--mono);
  color: var(--accent);
}
.stat-card .stat-name { font-size: 0.8rem; color: var(--text3); margin-top: 2px; }
.labs-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
  gap: 1.5rem;
}
.lab-card {
  background: var(--bg2); border: 1px solid var(--border);
  border-radius: var(--r-lg); padding: 1.5rem;
  display: flex; flex-direction: column; gap: 1rem;
  transition: all .2s;
}
.lab-card:hover { border-color: #3d4450; box-shadow: 0 4px 20px rgba(0,0,0,0.3); }
.lab-card.completed { border-color: rgba(63,185,80,0.4); }
.lab-card-header {
  display: flex; align-items: flex-start; justify-content: space-between; gap: 1rem;
}
.lab-card-title { font-size: 1.1rem; font-weight: 600; }
.lab-card-subtitle { font-size: 0.82rem; color: var(--text3); margin-top: 2px; font-family: var(--mono); }
.lab-card-badges { display: flex; flex-wrap: wrap; gap: 0.4rem; }
.lab-card-desc { font-size: 0.875rem; color: var(--text2); display: -webkit-box; -webkit-line-clamp: 3; -webkit-box-orient: vertical; overflow: hidden; }
.lab-card-footer {
  display: flex; align-items: center; justify-content: space-between;
  margin-top: auto; padding-top: 0.5rem; border-top: 1px solid var(--border);
}
.lab-meta { display: flex; align-items: center; gap: 0.8rem; font-size: 0.8rem; color: var(--text3); }
.lab-meta span { display: flex; align-items: center; gap: 0.3rem; }
.completed-badge {
  display: flex; align-items: center; gap: 0.3rem;
  font-size: 0.78rem; color: var(--green); font-weight: 600;
}

/* ── Auth pages ─────────────────────────────────────────────────────────────────── */
.auth-page { min-height: calc(100vh - 56px); display: flex; align-items: center; padding: 2rem 0; }
.auth-card {
  background: var(--bg2); border: 1px solid var(--border); border-radius: var(--r-lg);
  padding: 2.5rem; width: 100%;
}
.auth-logo {
  font-family: var(--mono); font-size: 1.5rem; font-weight: 700; text-align: center;
  margin-bottom: 0.4rem; color: var(--accent);
}
.auth-title { text-align: center; font-size: 1.4rem; margin-bottom: 0.4rem; }
.auth-subtitle { text-align: center; color: var(--text3); font-size: 0.875rem; margin-bottom: 2rem; }
.auth-form { display: flex; flex-direction: column; gap: 1.2rem; }
.auth-footer { text-align: center; margin-top: 1.5rem; font-size: 0.875rem; color: var(--text3); }
.auth-footer a { color: var(--accent); font-weight: 500; }

/* ── Lab page ─────────────────────────────────────────────────────────────────────── */
.lab-page { padding: 2rem 0 4rem; }
.lab-breadcrumb {
  display: flex; align-items: center; gap: 0.5rem;
  font-size: 0.82rem; color: var(--text3); margin-bottom: 1.5rem;
}
.lab-breadcrumb a { color: var(--text3); }
.lab-breadcrumb a:hover { color: var(--accent); }
.lab-breadcrumb-sep { color: var(--border); }
.lab-layout {
  display: grid; grid-template-columns: 360px 1fr; gap: 1.5rem; align-items: start;
}
@media (max-width: 900px) { .lab-layout { grid-template-columns: 1fr; } }

/* Lab sidebar */
.lab-sidebar { display: flex; flex-direction: column; gap: 1rem; position: sticky; top: 72px; }
.lab-info-card { background: var(--bg2); border: 1px solid var(--border); border-radius: var(--r-lg); overflow: hidden; }
.lab-info-header { padding: 1.2rem 1.4rem; border-bottom: 1px solid var(--border); }
.lab-info-body   { padding: 1.4rem; }
.lab-status-bar  { padding: 0.7rem 1.4rem; border-top: 1px solid var(--border); }
.lab-title-sm { font-size: 1.1rem; font-weight: 600; margin-bottom: 0.3rem; }
.lab-badges-row { display: flex; flex-wrap: wrap; gap: 0.4rem; }
.objective-list { list-style: none; display: flex; flex-direction: column; gap: 0.6rem; margin-top: 0.8rem; }
.objective-list li { display: flex; align-items: flex-start; gap: 0.5rem; font-size: 0.85rem; color: var(--text2); }
.objective-list li::before { content: '→'; color: var(--accent); font-family: var(--mono); flex-shrink: 0; }
.lab-desc { font-size: 0.875rem; color: var(--text2); margin-top: 0.5rem; }

/* Hints */
.hints-card { background: var(--bg2); border: 1px solid var(--border); border-radius: var(--r-lg); overflow: hidden; }
.hints-toggle {
  width: 100%; display: flex; align-items: center; justify-content: space-between;
  padding: 1rem 1.4rem; background: none; border: none; color: var(--text);
  cursor: pointer; font-family: var(--sans); font-size: 0.9rem; font-weight: 500;
}
.hints-toggle:hover { background: var(--bg3); }
.hints-toggle .arrow { font-size: 0.75rem; color: var(--text3); transition: transform .2s; }
.hints-toggle.open .arrow { transform: rotate(180deg); }
.hints-body { display: none; padding: 0 1.4rem 1.2rem; }
.hints-body.open { display: block; }
.hint-item {
  display: flex; gap: 0.8rem; padding: 0.75rem 0;
  border-top: 1px solid var(--border); font-size: 0.85rem;
  opacity: 0; pointer-events: none; filter: blur(4px);
  transition: all .3s;
}
.hint-item.revealed { opacity: 1; pointer-events: auto; filter: none; }
.hint-num {
  width: 22px; height: 22px; border-radius: 50%; flex-shrink: 0;
  background: var(--accent-glow); border: 1px solid rgba(0,229,255,0.3);
  font-family: var(--mono); font-size: 0.7rem; color: var(--accent);
  display: flex; align-items: center; justify-content: center; margin-top: 1px;
}
.hint-content { display: flex; flex-direction: column; gap: 0.2rem; flex: 1; min-width: 0; }
.hint-text { color: var(--text2); line-height: 1.55; }
.hint-tier {
  font-size: 0.65rem; font-family: var(--mono); font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.1em;
  color: var(--text3);
}
.hint-tier-direction { color: var(--blue); }
.hint-tier-mechanism  { color: var(--yellow); }
.hint-tier-technique  { color: var(--accent); }
.reveal-btn {
  margin-top: 0.8rem; width: 100%;
}

/* Attacker context */
.attacker-context {
  margin-top: 1rem;
  padding: 0.65rem 0.85rem;
  background: rgba(56,139,253,0.06);
  border: 1px solid rgba(56,139,253,0.2);
  border-radius: var(--r);
  font-size: 0.8rem; color: var(--text2); line-height: 1.5;
}
.attacker-context-label {
  font-size: 0.65rem; font-family: var(--mono); font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.08em;
  color: var(--blue); margin-bottom: 0.3rem;
}

/* Post-lab debrief */
.debrief-section {
  margin-top: 1.5rem;
  background: var(--bg2);
  border: 1px solid rgba(63,185,80,0.25);
  border-radius: var(--r-lg);
  padding: 1.4rem 1.6rem;
}
.debrief-header {
  display: flex; align-items: center; gap: 0.9rem;
  margin-bottom: 1.1rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--border);
}
.debrief-icon { font-size: 1.4rem; flex-shrink: 0; }
.debrief-body { display: flex; flex-direction: column; gap: 1rem; }
.debrief-block { display: flex; flex-direction: column; gap: 0.25rem; }
.debrief-label {
  font-size: 0.65rem; font-family: var(--mono); font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.1em; color: var(--green);
}
.debrief-block p { font-size: 0.875rem; color: var(--text2); line-height: 1.6; margin: 0; }

/* Flag submit */
.flag-card { background: var(--bg2); border: 1px solid var(--border); border-radius: var(--r-lg); padding: 1.2rem 1.4rem; }
.flag-card h4 { font-size: 0.9rem; margin-bottom: 0.8rem; display: flex; align-items: center; gap: 0.4rem; }
.flag-input-row { display: flex; gap: 0.5rem; }
.flag-input {
  flex: 1; background: var(--bg3); border: 1px solid var(--border);
  color: var(--text); border-radius: var(--r); padding: 0.5rem 0.75rem;
  font-family: var(--mono); font-size: 0.85rem; outline: none;
  transition: border-color .2s;
}
.flag-input:focus { border-color: var(--accent); }
.flag-feedback { font-size: 0.82rem; margin-top: 0.5rem; min-height: 18px; }
.flag-feedback.ok  { color: var(--green); }
.flag-feedback.err { color: var(--red); }

/* Completed banner */
.completed-banner {
  background: rgba(63,185,80,0.1); border: 1px solid rgba(63,185,80,0.4);
  border-radius: var(--r-lg); padding: 1rem 1.4rem;
  display: flex; align-items: center; gap: 0.75rem;
}
.completed-banner .check { font-size: 1.4rem; }
.completed-banner h4 { font-size: 0.95rem; color: var(--green); }
.completed-banner p  { font-size: 0.82rem; color: var(--text3); }

/* ── Chat interface ──────────────────────────────────────────────────────────────── */
.chat-panel {
  background: var(--bg2); border: 1px solid var(--border); border-radius: var(--r-lg);
  display: flex; flex-direction: column; height: 620px;
}
.chat-header {
  padding: 0.9rem 1.2rem; border-bottom: 1px solid var(--border);
  display: flex; align-items: center; gap: 0.75rem;
}
.chat-avatar {
  width: 36px; height: 36px; border-radius: var(--r);
  background: var(--accent-glow); border: 1px solid rgba(0,229,255,0.3);
  display: flex; align-items: center; justify-content: center; font-size: 1.1rem;
}
.chat-header-info { flex: 1; }
.chat-header-name  { font-weight: 600; font-size: 0.9rem; }
.chat-header-status {
  font-size: 0.75rem; color: var(--text3);
  display: flex; align-items: center; gap: 0.3rem;
}
.status-dot {
  width: 6px; height: 6px; border-radius: 50%; background: var(--green);
  box-shadow: 0 0 6px var(--green);
}
.chat-target { font-family: var(--mono); font-size: 0.75rem; color: var(--text3); }

.chat-messages {
  flex: 1; overflow-y: auto; padding: 1rem;
  display: flex; flex-direction: column; gap: 0.75rem;
  scrollbar-width: thin; scrollbar-color: var(--border) transparent;
}
.chat-messages::-webkit-scrollbar { width: 4px; }
.chat-messages::-webkit-scrollbar-track { background: transparent; }
.chat-messages::-webkit-scrollbar-thumb { background: var(--border); border-radius: 2px; }

.chat-message { display: flex; flex-direction: column; max-width: 85%; }
.chat-user    { align-self: flex-end; align-items: flex-end; }
.chat-assistant { align-self: flex-start; align-items: flex-start; }
.chat-system  { align-self: center; align-items: center; width: 100%; max-width: none; }
.message-bubble {
  padding: 0.7rem 1rem; border-radius: var(--r); font-size: 0.875rem; line-height: 1.55;
  word-break: break-word; white-space: pre-wrap;
}
.chat-user .message-bubble {
  background: var(--accent); color: #000; border-bottom-right-radius: 2px;
}
.chat-assistant .message-bubble {
  background: var(--bg3); border: 1px solid var(--border); border-bottom-left-radius: 2px;
}
.chat-system .message-bubble {
  background: transparent; color: var(--text3); font-size: 0.78rem;
  font-family: var(--mono); text-align: center;
}
.message-time { font-size: 0.68rem; color: var(--text3); margin-top: 3px; }

/* Typing indicator */
.typing-indicator {
  display: none; align-self: flex-start; align-items: center;
  background: var(--bg3); border: 1px solid var(--border);
  border-radius: var(--r); padding: 0.7rem 1rem;
}
.typing-indicator.show { display: flex; }
.typing-dot {
  width: 6px; height: 6px; border-radius: 50%; background: var(--text3);
  margin: 0 2px; animation: bounce 1.2s infinite;
}
.typing-dot:nth-child(2) { animation-delay: 0.2s; }
.typing-dot:nth-child(3) { animation-delay: 0.4s; }
@keyframes bounce { 0%, 60%, 100% { transform: none; } 30% { transform: translateY(-5px); } }

/* Flag detected toast */
.flag-toast {
  display: none; align-items: center; gap: 0.6rem;
  background: rgba(63,185,80,0.15); border: 1px solid rgba(63,185,80,0.4);
  color: var(--green); padding: 0.6rem 1rem; border-radius: var(--r);
  font-size: 0.82rem; font-weight: 500; margin: 0 1rem;
  animation: pulse 2s ease infinite;
}
.flag-toast.show { display: flex; }
@keyframes pulse { 0%,100% { box-shadow: none; } 50% { box-shadow: 0 0 12px rgba(63,185,80,0.3); } }

/* Chat input */
.chat-input-area {
  padding: 0.75rem 1rem; border-top: 1px solid var(--border);
  display: flex; gap: 0.5rem; align-items: flex-end;
}
.chat-input {
  flex: 1; background: var(--bg3); border: 1px solid var(--border);
  color: var(--text); border-radius: var(--r); padding: 0.6rem 0.9rem;
  font-size: 0.875rem; font-family: var(--sans); outline: none; resize: none;
  max-height: 120px; line-height: 1.5; transition: border-color .2s;
}
.chat-input:focus { border-color: var(--accent); }
.chat-input::placeholder { color: var(--text3); }

/* ── Footer ─────────────────────────────────────────────────────────────────────── */
.footer {
  border-top: 1px solid var(--border); padding: 1.2rem 0;
  text-align: center; margin-top: auto;
}
.footer-text { font-size: 0.8rem; color: var(--text3); }

/* ── Utility ─────────────────────────────────────────────────────────────────────── */
.tag {
  display: inline-block; font-family: var(--mono); font-size: 0.73rem;
  color: var(--text3); background: var(--bg3); border: 1px solid var(--border);
  padding: 2px 8px; border-radius: 4px;
}
.section-label {
  font-size: 0.78rem; font-weight: 600; text-transform: uppercase;
  letter-spacing: 0.1em; color: var(--text3); margin-bottom: 0.5rem;
}
.lock-icon { font-size: 1rem; }

/* ── Catalog panel (Lab 2) ──────────────────────────────────────────────────── */
.catalog-panel {
  background: var(--bg2); border: 1px solid var(--border);
  border-radius: var(--r-lg); margin-bottom: 1rem; overflow: hidden;
}
.catalog-panel-header {
  display: flex; align-items: center; justify-content: space-between;
  padding: 0.6rem 1rem; background: var(--bg3);
  border-bottom: 1px solid var(--border); font-size: 0.82rem; font-weight: 600;
}
.catalog-body { overflow: auto; max-height: 195px; }
.catalog-table { width: 100%; border-collapse: collapse; font-size: 0.77rem; }
.catalog-table thead th {
  padding: 0.38rem 0.7rem; text-align: left;
  color: var(--text3); font-size: 0.69rem; font-weight: 600;
  text-transform: uppercase; letter-spacing: 0.05em;
  position: sticky; top: 0; background: var(--bg2);
  border-bottom: 1px solid var(--border);
}
.catalog-table tbody td {
  padding: 0.38rem 0.7rem;
  border-bottom: 1px solid rgba(255,255,255,0.04); color: var(--text2);
}
.catalog-table tbody tr:last-child td { border-bottom: none; }
.catalog-table tbody tr:hover td { background: rgba(255,255,255,0.025); }
.price-cell { font-family: var(--mono); color: var(--accent); font-weight: 500; }
@keyframes priceFlash {
  0%   { background: rgba(63,185,80,0.4); color: var(--green); }
  100% { background: transparent; }
}
.price-changed { animation: priceFlash 3s ease-out forwards; }

/* ── Tool call bubbles (Lab 2) ──────────────────────────────────────────────── */
.chat-tool { align-self: stretch !important; max-width: 100% !important; }
.tool-bubble {
  background: rgba(18,30,18,0.95) !important;
  border: 1px solid rgba(63,185,80,0.22) !important;
  font-family: var(--mono) !important;
  font-size: 0.72rem !important;
  padding: 0.55rem 0.9rem !important;
  width: 100%;
}
.tool-header { display: flex; align-items: center; gap: 0.4rem; margin-bottom: 0.25rem; }
.tool-name { color: var(--green); font-weight: 600; font-size: 0.77rem; }
.tool-args { color: var(--text3); margin-bottom: 0.25rem; }
.tool-result {
  color: var(--text2); white-space: pre-wrap; word-break: break-all;
  max-height: 110px; overflow-y: auto;
  border-top: 1px solid rgba(255,255,255,0.06);
  padding-top: 0.25rem; margin-top: 0.22rem;
}
.tool-result.tool-flag { color: var(--green); font-weight: 600; }

/* ── Learn ─────────────────────────────────────────────────────────────────── */
.learn-modal-overlay {
  display: none;
  position: fixed; inset: 0; z-index: 1000;
  background: rgba(0,0,0,0.72);
  backdrop-filter: blur(4px);
  align-items: center; justify-content: center;
  padding: 1.5rem;
}
.learn-modal {
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  width: 100%; max-width: 860px;
  max-height: 90vh;
  display: flex; flex-direction: column;
  overflow: hidden;
}
.learn-modal-bar {
  display: flex; justify-content: flex-end;
  padding: 0.75rem 1rem 0;
  flex-shrink: 0;
}
.learn-modal-scroll {
  overflow-y: auto;
  padding: 0.5rem 1.75rem 1.75rem;
  flex: 1;
}
.learn-modal-close {
  background: var(--bg3);
  border: 1px solid var(--border);
  border-radius: 6px;
  color: var(--text2);
  font-size: 0.9rem;
  width: 30px; height: 30px;
  display: flex; align-items: center; justify-content: center;
  cursor: pointer;
}
.learn-modal-close:hover { border-color: var(--accent); color: var(--accent); }
.learn-modal-head {
  display: flex; align-items: flex-start;
  justify-content: space-between; gap: 1rem;
}
.learn-topic-card { cursor: pointer; }
.learn-hero {
  padding: 4.5rem 0 1.5rem;
  position: relative;
  overflow: hidden;
}
.learn-hero::before {
  content: '';
  position: absolute; inset: 0;
  background:
    radial-gradient(circle at 18% 22%, rgba(56,139,253,0.14), transparent 28%),
    radial-gradient(circle at 80% 14%, rgba(0,229,255,0.12), transparent 26%);
  pointer-events: none;
}
.learn-hero-copy {
  max-width: 720px;
  position: relative;
  z-index: 1;
}
.learn-hero h1 {
  max-width: 760px;
  margin-bottom: 0.9rem;
}
.learn-hero p {
  max-width: 620px;
  font-size: 1rem;
}
.learn-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(270px, 1fr));
  gap: 1.1rem;
}
.learn-card {
  display: flex;
  flex-direction: column;
  gap: 0.9rem;
  padding: 1.15rem;
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  background:
    linear-gradient(180deg, rgba(255,255,255,0.02), rgba(255,255,255,0)),
    var(--bg2);
  color: var(--text);
  transition: transform .18s ease, border-color .18s ease, box-shadow .18s ease;
}
.learn-card:hover {
  transform: translateY(-2px);
  border-color: rgba(0,229,255,0.28);
  box-shadow: 0 14px 40px rgba(0,0,0,0.28);
  color: var(--text);
}
.learn-card-top,
.learn-card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.8rem;
}
.learn-chip,
.learn-time,
.learn-lab-pill {
  display: inline-flex;
  align-items: center;
  border-radius: 999px;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.03em;
}
.learn-chip {
  padding: 4px 10px;
  color: var(--accent);
  background: rgba(0,229,255,0.08);
  border: 1px solid rgba(0,229,255,0.18);
}
.learn-time {
  padding: 4px 10px;
  color: var(--text3);
  background: var(--bg3);
  border: 1px solid var(--border);
}
.learn-card h3 {
  font-size: 1.05rem;
}
.learn-card p {
  font-size: 0.86rem;
}
.learn-flow-preview {
  display: grid;
  gap: 0.45rem;
}
.learn-flow-mini {
  position: relative;
  padding: 0.65rem 0.75rem 0.65rem 1rem;
  background: rgba(255,255,255,0.025);
  border: 1px solid rgba(255,255,255,0.06);
  border-radius: var(--r);
  color: var(--text2);
  font-size: 0.8rem;
}
.learn-flow-mini::before {
  content: '';
  position: absolute;
  left: 0.4rem;
  top: 0.72rem;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 10px rgba(0,229,255,0.55);
}
.learn-lab-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}
.learn-lab-pill {
  padding: 4px 9px;
  color: var(--blue);
  background: rgba(56,139,253,0.1);
  border: 1px solid rgba(56,139,253,0.2);
}
.learn-open {
  color: var(--accent);
  font-size: 0.82rem;
  font-weight: 600;
}
.learn-topic-page {
  padding-bottom: 4rem;
}
.learn-topic-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1.2rem;
  margin-bottom: 1.5rem;
}
.learn-topic-summary {
  max-width: 720px;
  margin-top: 0.5rem;
  font-size: 0.98rem;
}
.learn-topic-meta {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  flex-wrap: wrap;
}
.learn-topic-grid {
  display: grid;
  grid-template-columns: 1.3fr 0.9fr;
  gap: 1rem;
}
.learn-panel {
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  padding: 1rem;
}
.learn-panel-wide {
  grid-column: 1 / -1;
}
.learn-flowchart {
  display: grid;
  gap: 0.55rem;
}
.learn-flow-step {
  display: grid;
  grid-template-columns: 38px 1fr;
  gap: 0.75rem;
  align-items: start;
  padding: 0.85rem 0.95rem;
  background:
    linear-gradient(90deg, rgba(0,229,255,0.04), transparent 70%),
    var(--bg3);
  border: 1px solid rgba(0,229,255,0.1);
  border-radius: var(--r);
}
.learn-flow-num {
  width: 38px;
  height: 38px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 10px;
  background: rgba(0,229,255,0.1);
  border: 1px solid rgba(0,229,255,0.22);
  color: var(--accent);
  font-family: var(--mono);
  font-size: 0.8rem;
  font-weight: 600;
}
.learn-flow-arrow {
  text-align: center;
  color: var(--text3);
  font-size: 1rem;
  line-height: 1;
}
.learn-code-list {
  display: grid;
  gap: 0.45rem;
}
.learn-code-line {
  padding: 0.72rem 0.8rem;
  background: #0b1320;
  border: 1px solid rgba(56,139,253,0.16);
  border-radius: var(--r);
  color: #b8d6ff;
  font-family: var(--mono);
  font-size: 0.78rem;
  line-height: 1.5;
}
.learn-tip-list {
  display: grid;
  gap: 0.55rem;
}
.learn-tip {
  padding: 0.8rem 0.85rem;
  border-radius: var(--r);
  background: rgba(210,153,34,0.08);
  border: 1px solid rgba(210,153,34,0.16);
  color: #e7c879;
  font-size: 0.84rem;
}
.learn-lab-links {
  display: grid;
  gap: 0.65rem;
}
.learn-lab-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.9rem;
  border-radius: var(--r);
  border: 1px solid rgba(255,255,255,0.06);
  background: var(--bg3);
  color: var(--text);
}
.learn-lab-card:hover {
  border-color: rgba(0,229,255,0.24);
  color: var(--text);
}
.learn-lab-kicker {
  font-family: var(--mono);
  color: var(--text3);
  font-size: 0.72rem;
  margin-bottom: 0.2rem;
}
.learn-lab-title {
  font-size: 0.92rem;
  font-weight: 600;
}

/* ── Learn: LLM studio ─────────────────────────────────────────────────────── */
.learn-exercise-page {
  padding-top: 2.5rem;
  padding-bottom: 4rem;
}
.learn-studio-hero {
  margin-bottom: 1.75rem;
  padding: 1.5rem;
  border: 1px solid rgba(56,139,253,0.14);
  border-radius: var(--r-lg);
  background:
    radial-gradient(circle at top left, rgba(56,139,253,0.14), transparent 28%),
    radial-gradient(circle at right center, rgba(0,229,255,0.08), transparent 26%),
    linear-gradient(180deg, rgba(255,255,255,0.02), rgba(255,255,255,0)),
    var(--bg2);
}
.learn-studio-hero h1 {
  margin-top: 0.35rem;
  font-size: 2rem;
}
.learn-studio-hero p {
  max-width: 720px;
  margin-top: 0.55rem;
  color: var(--text2);
}
.learn-studio-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 1rem;
}
.llm-overview-card {
  background:
    linear-gradient(135deg, rgba(56,139,253,0.08), transparent 55%),
    var(--bg2);
}
.llm-overview-points {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0.8rem;
}
.llm-overview-point {
  display: grid;
  gap: 0.35rem;
  padding: 0.95rem;
  border-radius: var(--r);
  background: rgba(255,255,255,0.03);
  border: 1px solid rgba(255,255,255,0.06);
}
.llm-overview-point strong {
  color: var(--text);
  font-size: 0.88rem;
}
.llm-overview-point span {
  color: var(--text2);
  font-size: 0.83rem;
  line-height: 1.55;
}
.llm-panel-inputs {
  display: grid;
  gap: 0.75rem;
}
.llm-label {
  display: block;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--text3);
  text-transform: uppercase;
}
.llm-select,
.llm-textarea {
  width: 100%;
  border: 1px solid var(--border);
  border-radius: var(--r);
  background: var(--bg3);
  color: var(--text);
  font-family: var(--sans);
  font-size: 0.9rem;
}
.llm-select {
  padding: 0.75rem 0.85rem;
}
.llm-textarea {
  padding: 0.85rem;
  resize: vertical;
  min-height: 132px;
}
.llm-toggle-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.llm-checkbox {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  color: var(--text2);
  font-size: 0.86rem;
}
.llm-context-box {
  padding: 0.95rem;
  border-radius: var(--r);
  background: rgba(0,229,255,0.06);
  border: 1px solid rgba(0,229,255,0.15);
  transition: opacity .18s ease, filter .18s ease;
}
.llm-context-box.disabled {
  opacity: 0.48;
  filter: saturate(0.6);
}
.llm-context-kicker {
  margin-bottom: 0.35rem;
  color: var(--accent);
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}
.llm-context-box p {
  margin: 0;
  color: var(--text2);
  font-size: 0.84rem;
  line-height: 1.6;
}
.llm-run-btn {
  width: 100%;
  justify-content: center;
}
.llm-prompt-stack,
.llm-note-list,
.llm-token-list {
  display: grid;
  gap: 0.65rem;
}
.llm-prompt-block {
  padding: 0.85rem 0.95rem;
  border-radius: var(--r);
  background: var(--bg3);
  border: 1px solid var(--border);
  color: var(--text2);
  font-size: 0.84rem;
  line-height: 1.6;
  white-space: pre-wrap;
}
.llm-prompt-block.muted,
.llm-token-empty {
  color: var(--text3);
}
.llm-prompt-context {
  border-color: rgba(0,229,255,0.18);
  background: linear-gradient(90deg, rgba(0,229,255,0.06), transparent 70%), var(--bg3);
}
.llm-role {
  display: block;
  margin-bottom: 0.45rem;
  color: var(--accent);
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
}
.llm-helper {
  margin-top: 0.25rem;
  margin-bottom: 0.8rem;
  color: var(--text3);
  font-size: 0.83rem;
  line-height: 1.55;
}
.llm-token {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.75rem 0.85rem;
  border-radius: var(--r);
  background: var(--bg3);
  border: 1px solid var(--border);
  color: var(--text2);
  font-family: var(--mono);
  font-size: 0.8rem;
}
.llm-token.selected {
  border-color: rgba(63,185,80,0.32);
  background: linear-gradient(90deg, rgba(63,185,80,0.08), transparent 80%), var(--bg3);
  color: var(--text);
}
.llm-token-word {
  font-weight: 600;
}
.llm-token-prob {
  color: var(--text3);
}
.llm-answer-box {
  min-height: 136px;
  padding: 1rem;
  border-radius: var(--r);
  background: #0b1320;
  border: 1px solid rgba(56,139,253,0.18);
  color: #d7e7ff;
  font-size: 0.9rem;
  line-height: 1.7;
}
.llm-note {
  padding: 0.82rem 0.9rem;
  border-radius: var(--r);
  background: rgba(210,153,34,0.08);
  border: 1px solid rgba(210,153,34,0.16);
  color: #e7c879;
  font-size: 0.84rem;
  line-height: 1.55;
}

/* ── Learn: quiz ─────────────────────────────────────────────────────────────────── */
.quiz-section { display: flex; flex-direction: column; gap: 1.1rem; }
.quiz-question.answered .quiz-option { cursor: default; }
.quiz-q { font-size: 0.88rem; color: var(--text); font-weight: 500; margin-bottom: 0.5rem; }
.quiz-options { display: flex; flex-direction: column; gap: 0.3rem; }
.quiz-option {
  padding: 0.5rem 0.8rem;
  background: var(--bg3); border: 1px solid var(--border);
  border-radius: var(--r); font-size: 0.82rem; color: var(--text2);
  cursor: pointer; transition: all .15s; text-align: left; width: 100%;
  font-family: var(--sans);
}
.quiz-option:hover:not(:disabled) { border-color: var(--accent); color: var(--text); }
.quiz-option.correct { border-color: var(--green); color: var(--green); background: rgba(63,185,80,0.07); }
.quiz-option.wrong   { border-color: var(--red);   color: var(--red);   background: rgba(248,81,73,0.07); }

/* ── Learn: annotated transcript ──────────────────────────────────────────────────── */
.transcript-section { display: flex; flex-direction: column; gap: 0.75rem; }
.transcript-entry { display: flex; flex-direction: column; gap: 0.25rem; }
.transcript-role {
  font-size: 0.63rem; font-family: var(--mono); font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.1em; color: var(--text3);
}
.role-system          { color: var(--yellow); }
.role-user            { color: var(--blue); }
.role-assistant       { color: var(--accent); }
.role-tool_result     { color: var(--red); }
.role-email_content   { color: var(--yellow); }
.role-rag_retrieval   { color: var(--blue); }
.role-tool_description{ color: var(--red); }
.transcript-content {
  font-family: var(--mono); font-size: 0.76rem; color: var(--text2);
  background: var(--bg3); border: 1px solid var(--border);
  border-radius: var(--r); padding: 0.5rem 0.75rem;
  white-space: pre-wrap; word-break: break-word;
}
.transcript-note { font-size: 0.74rem; color: var(--text3); font-style: italic; padding-left: 0.25rem; }

/* ── Responsive ─────────────────────────────────────────────────────────────────── */
@media (max-width: 640px) {
  .hero { padding: 3.5rem 0 3rem; }
  .hero-stats { gap: 1.5rem; }
  .labs-grid { grid-template-columns: 1fr; }
  .nav-link { display: none; }
  .auth-card { padding: 1.5rem; }
  .chat-panel { height: 500px; }
  .learn-topic-head { flex-direction: column; }
  .learn-topic-grid { grid-template-columns: 1fr; }
  .learn-studio-grid { grid-template-columns: 1fr; }
  .llm-overview-points { grid-template-columns: 1fr; }
  .learn-studio-hero { padding: 1.15rem; }
  .learn-studio-hero h1 { font-size: 1.55rem; }
}