:root {
  --paper: #FAF9F6;
  --ink: #16181B;
  --ink-soft: #52565C;
  --rule: #D8D6D0;
  --up: #1E6B45;
  --down: #A3312A;
  --live: #C7511F;
  --display: 'Source Serif 4', Georgia, serif;
  --mono: 'IBM Plex Mono', 'Courier New', monospace;
  --body: 'Inter', -apple-system, sans-serif;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--body);
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}

.wrap {
  max-width: 760px;
  margin: 0 auto;
  padding: 0 24px;
}

a { color: inherit; }

/* ---------- Masthead ---------- */
.masthead {
  border-bottom: 1px solid var(--rule);
  position: sticky;
  top: 0;
  background: var(--paper);
  z-index: 10;
}
.masthead-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 64px;
}
.wordmark {
  font-family: var(--display);
  font-size: 1.15rem;
  font-weight: 600;
  letter-spacing: 0.01em;
}
.masthead-nav {
  display: flex;
  gap: 28px;
  align-items: center;
  font-size: 0.9rem;
}
.masthead-nav a {
  text-decoration: none;
  color: var(--ink-soft);
}
.masthead-nav a:hover { color: var(--ink); }
.nav-cta {
  border: 1px solid var(--ink);
  padding: 7px 16px;
  border-radius: 2px;
  color: var(--ink) !important;
}

/* ---------- Hero ---------- */
.hero {
  padding: 84px 0 64px;
  border-bottom: 1px solid var(--rule);
}
.eyebrow {
  font-family: var(--mono);
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--live);
  margin: 0 0 20px;
}
.hero h1 {
  font-family: var(--display);
  font-size: 2.4rem;
  font-weight: 600;
  line-height: 1.18;
  letter-spacing: -0.01em;
  margin: 0 0 28px;
}
.hero-sub {
  font-size: 1.05rem;
  color: var(--ink-soft);
  max-width: 58ch;
  margin: 0 0 32px;
}
.hero-link {
  font-family: var(--mono);
  font-size: 0.9rem;
  text-decoration: none;
  border-bottom: 1px solid var(--ink);
  padding-bottom: 2px;
}

/* ---------- Reader ---------- */
.reader {
  scroll-margin-top: 72px;
  padding: 56px 0;
  border-bottom: 1px solid var(--rule);
}
.reader-head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 8px;
}
.reader h2 {
  font-family: var(--display);
  font-size: 1.5rem;
  font-weight: 600;
  margin: 0;
}
.status {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--mono);
  font-size: 0.8rem;
  color: var(--ink-soft);
}
.status-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--ink-soft);
  display: inline-block;
}
.status-dot.live {
  background: var(--live);
  animation: pulse 1.6s ease-in-out infinite;
}
.status-dot.connected {
  background: var(--up);
}
@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.35; }
}

.reader-note {
  font-size: 0.92rem;
  color: var(--ink-soft);
  max-width: 62ch;
  margin: 0 0 32px;
}

.ticker-board {
  border-top: 1px solid var(--ink);
  border-bottom: 1px solid var(--ink);
}
.ticker-row {
  display: grid;
  grid-template-columns: 1fr auto auto;
  align-items: center;
  gap: 20px;
  padding: 22px 4px;
  border-bottom: 1px solid var(--rule);
}
.ticker-row:last-child { border-bottom: none; }

.ticker-name {
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.ticker-label {
  font-family: var(--mono);
  font-size: 0.85rem;
  font-weight: 500;
  letter-spacing: 0.03em;
}
.ticker-sub {
  font-size: 0.78rem;
  color: var(--ink-soft);
}
.ticker-sub.cas-active {
  color: var(--live);
  font-weight: 500;
}

.ticker-value {
  font-family: var(--mono);
  font-size: 1.6rem;
  font-weight: 500;
  font-variant-numeric: tabular-nums;
  text-align: right;
  min-width: 9ch;
}

.ticker-change {
  font-family: var(--mono);
  font-size: 0.9rem;
  font-variant-numeric: tabular-nums;
  text-align: right;
  min-width: 7ch;
  color: var(--ink-soft);
}
.ticker-change.up { color: var(--up); }
.ticker-change.down { color: var(--down); }

.reader-updated {
  font-family: var(--mono);
  font-size: 0.75rem;
  color: var(--ink-soft);
  margin: 16px 0 0;
}

/* ---------- Course ---------- */
.social-icons {
  display: flex;
  align-items: center;
  gap: 14px;
}
.social-icons a {
  display: flex;
  color: var(--ink-soft);
  transition: color 0.15s ease;
}
.social-icons a:hover {
  color: var(--live);
}

.community {
  scroll-margin-top: 72px;
  padding: 56px 0;
  border-bottom: 1px solid var(--rule);
}
.community-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
}
.community-item {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}
.community-label {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--live);
  margin-bottom: 10px;
}
.community-item h3 {
  font-family: var(--display);
  font-size: 1.2rem;
  font-weight: 600;
  margin: 0 0 10px;
  line-height: 1.3;
}
.community-item p {
  font-size: 0.92rem;
  color: var(--ink-soft);
  margin: 0 0 16px;
}
.community-link {
  font-family: var(--mono);
  font-size: 0.85rem;
  text-decoration: none;
  border-bottom: 1px solid var(--ink);
  padding-bottom: 2px;
}

.course {
  scroll-margin-top: 72px;
  padding: 64px 0;
  border-bottom: 1px solid var(--rule);
}
.course-grid {
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  gap: 56px;
}
.course-copy h2 {
  font-family: var(--display);
  font-size: 1.6rem;
  font-weight: 600;
  line-height: 1.25;
  margin: 0 0 20px;
}
.course-copy p {
  color: var(--ink-soft);
  font-size: 0.97rem;
  margin: 0 0 16px;
}
.course-list {
  display: flex;
  flex-direction: column;
}
.course-item {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 16px 0;
  border-bottom: 1px solid var(--rule);
}
.course-item:first-child { padding-top: 0; }
.course-item-label {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--ink-soft);
}
.course-item-name {
  font-size: 0.98rem;
}

/* ---------- Enroll ---------- */
.enroll {
  scroll-margin-top: 72px;
  padding: 72px 0;
  text-align: center;
}
.enroll h2 {
  font-family: var(--display);
  font-size: 1.7rem;
  font-weight: 600;
  margin: 0 0 12px;
}
.enroll p {
  color: var(--ink-soft);
  margin: 0 0 28px;
}
.enroll-cta {
  display: inline-block;
  font-family: var(--mono);
  font-size: 0.9rem;
  text-decoration: none;
  background: var(--ink);
  color: var(--paper);
  padding: 13px 28px;
  border: none;
  border-radius: 2px;
  cursor: pointer;
}
.enroll-cta:disabled {
  opacity: 0.6;
  cursor: default;
}

.enroll-form {
  max-width: 420px;
  margin: 0 auto;
  text-align: left;
}
.form-row {
  margin-bottom: 16px;
}
.form-row label {
  display: block;
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--ink-soft);
  margin-bottom: 6px;
}
.form-row .optional {
  font-style: italic;
  color: var(--ink-soft);
}
.form-row input,
.form-row textarea {
  width: 100%;
  font-family: var(--body);
  font-size: 0.95rem;
  padding: 10px 12px;
  border: 1px solid var(--rule);
  border-radius: 2px;
  background: var(--paper);
  color: var(--ink);
}
.form-row input:focus,
.form-row textarea:focus {
  outline: none;
  border-color: var(--ink);
}
.form-row textarea {
  resize: vertical;
}

.form-status {
  font-size: 0.9rem;
  margin: 14px 0 0;
  min-height: 1.2em;
  padding: 0;
  border-radius: 3px;
  transition: padding 0.15s ease;
}
.form-status:not(:empty) {
  padding: 12px 14px;
}
.form-status-ok {
  color: var(--up);
  background: #E8F3ED;
  border: 1px solid var(--up);
}
.form-status-error {
  color: var(--down);
  background: #F7EAE9;
  border: 1px solid var(--down);
}

/* ---------- Footer ---------- */
.site-footer {
  border-top: 1px solid var(--rule);
  padding: 28px 0 40px;
}
.footer-row {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 8px;
  font-size: 0.8rem;
  color: var(--ink-soft);
}
.footer-note { max-width: 46ch; text-align: right; }

/* ---------- Responsive ---------- */
@media (max-width: 680px) {
  .reader, .community, .course, .enroll { scroll-margin-top: 120px; }
  .hero { padding: 56px 0 40px; }
  .hero h1 { font-size: 1.8rem; }
  .course-grid { grid-template-columns: 1fr; gap: 36px; }
  .ticker-row { grid-template-columns: 1fr; gap: 6px; text-align: left; }
  .ticker-value, .ticker-change { text-align: left; }
  .footer-row { flex-direction: column; }
  .footer-note { text-align: left; }

  .masthead-row { flex-wrap: wrap; height: auto; padding: 14px 0; gap: 10px; }
  .wordmark { font-size: 1.05rem; }
  .masthead-nav { flex-wrap: wrap; gap: 12px; width: 100%; justify-content: flex-start; align-items: center; }
  .masthead-nav > a:not(.nav-cta) { font-size: 0.82rem; }
  .social-icons { gap: 12px; margin-left: auto; }
  .nav-cta { padding: 6px 14px; font-size: 0.82rem; }

  .community-grid { grid-template-columns: 1fr; gap: 0; }
  .community-item {
    padding: 24px 0;
    border-bottom: 1px solid var(--rule);
  }
  .community-item:last-child { border-bottom: none; padding-bottom: 0; }
  .community-item:first-child { padding-top: 0; }
}

/* ---------- Reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  .status-dot.live { animation: none; }
}