/* IP TALK — style.css
   Palette: cool paper base, deep navy ink, amber "signal" accent, teal secondary.
   Type: Fraunces (headline/brand), Inter (UI/body), IBM Plex Mono (room data only).
*/

:root {
  --paper: #EEF1EE;
  --panel: #FFFFFF;
  --ink: #142B3D;
  --ink-soft: #46586B;
  --line: #D7DCD6;
  --amber: #E8933A;
  --amber-deep: #C9761F;
  --teal: #2E8677;
  --green-live: #3FA66B;
  --danger: #C4453C;

  --font-display: 'Fraunces', serif;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'IBM Plex Mono', 'SF Mono', monospace;

  --radius: 10px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  line-height: 1.5;
}

.wrap {
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 24px;
}

a { color: inherit; }

/* ---------- topbar ---------- */
.topbar {
  border-bottom: 1px solid var(--line);
  background: var(--paper);
}
.topbar-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}
.brand {
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 600;
  letter-spacing: 0.01em;
}
.brand-mark {
  background: var(--ink);
  color: var(--amber);
  padding: 3px 8px;
  border-radius: 6px;
  margin-right: 6px;
  font-family: var(--font-mono);
  font-size: 17px;
}
.brand-mark.small { font-size: 14px; padding: 2px 6px; }
.brand-word.small { font-size: 16px; }

.topbar-cta {
  text-decoration: none;
  font-weight: 600;
  font-size: 14px;
  padding: 10px 18px;
  border-radius: 999px;
  background: var(--ink);
  color: var(--paper);
}
.topbar-cta:hover { background: var(--amber-deep); }

/* ---------- hero ---------- */
.hero { padding: 72px 0 56px; }
.hero-grid {
  display: grid;
  grid-template-columns: 1.05fr 1fr;
  gap: 48px;
  align-items: center;
}
.hero-eyebrow {
  color: var(--teal);
  font-weight: 600;
  font-size: 14px;
  margin: 0 0 14px;
}
.hero-copy h1 {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: clamp(34px, 4.4vw, 52px);
  line-height: 1.08;
  margin: 0 0 22px;
  max-width: 15ch;
}
.hero-lede {
  font-size: 17px;
  color: var(--ink-soft);
  max-width: 46ch;
  margin: 0 0 30px;
}
.hero-actions { display: flex; gap: 14px; flex-wrap: wrap; }

.btn {
  display: inline-block;
  text-decoration: none;
  font-weight: 600;
  font-size: 15px;
  padding: 13px 24px;
  border-radius: 8px;
  border: 1px solid transparent;
  cursor: pointer;
  font-family: var(--font-body);
  transition: background 0.15s ease, border-color 0.15s ease, color 0.15s ease;
}
.btn-primary { background: var(--amber); color: var(--ink); }
.btn-primary:hover { background: var(--amber-deep); color: #fff; }
.btn-ghost { background: transparent; color: var(--ink); border-color: var(--ink); }
.btn-ghost:hover { background: var(--ink); color: var(--paper); }
.btn-block { width: 100%; text-align: center; }
.btn-small { padding: 9px 16px; font-size: 14px; }

/* diagram */
.hero-diagram svg { width: 100%; height: auto; }
.net-box { fill: var(--panel); stroke: var(--line); stroke-width: 1.5; }
.net-label { font-family: var(--font-body); font-size: 12px; fill: var(--ink-soft); font-weight: 600; }
.node-dot { fill: var(--teal); }
.node-label { font-family: var(--font-body); font-size: 13px; fill: var(--ink); font-weight: 600; }
.link-line { fill: none; stroke: var(--amber); stroke-width: 2; stroke-dasharray: 5 6; }
.hub-box { fill: var(--ink); }
.hub-label { font-family: var(--font-mono); font-size: 15px; fill: var(--amber); font-weight: 500; }
.hub-sub { font-family: var(--font-mono); font-size: 12px; fill: #C7D2DA; }

/* ---------- how it works ---------- */
.how { padding: 24px 0 64px; }
.how h2 {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 30px;
  margin: 0 0 28px;
}
.how-steps {
  list-style: none;
  margin: 0 0 28px;
  padding: 0;
  display: grid;
  gap: 22px;
}
.how-steps li {
  display: grid;
  grid-template-columns: 40px 1fr;
  gap: 16px;
  padding: 20px 0;
  border-top: 1px solid var(--line);
}
.step-index {
  font-family: var(--font-mono);
  font-size: 15px;
  color: var(--amber-deep);
  padding-top: 2px;
}
.how-steps h3 { margin: 0 0 6px; font-size: 17px; }
.how-steps p { margin: 0; color: var(--ink-soft); max-width: 60ch; }

.how-note {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px 20px;
  color: var(--ink-soft);
  font-size: 14.5px;
  max-width: 74ch;
}

/* ---------- join section ---------- */
.join-section { padding: 8px 0 72px; }
.join-wrap {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 40px;
  background: var(--ink);
  color: var(--paper);
  border-radius: 16px;
  padding: 44px;
}
.join-intro h2 {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 28px;
  margin: 0 0 12px;
}
.join-intro p { color: #C7D2DA; max-width: 34ch; }

.join-panel {
  background: var(--panel);
  color: var(--ink);
  border-radius: 12px;
  padding: 28px;
  display: grid;
  gap: 16px;
  align-content: start;
}
.field { display: grid; gap: 6px; }
.field label { font-size: 13px; font-weight: 600; color: var(--ink-soft); }
.field input {
  font-family: var(--font-mono);
  font-size: 15px;
  padding: 12px 14px;
  border-radius: 7px;
  border: 1.5px solid var(--line);
  background: var(--paper);
  color: var(--ink);
}
.field input:focus {
  outline: none;
  border-color: var(--amber-deep);
  background: #fff;
}
#username { font-family: var(--font-body); }
.form-error {
  margin: 0;
  color: var(--danger);
  font-size: 13.5px;
  min-height: 18px;
}

/* ---------- footer ---------- */
.site-footer { border-top: 1px solid var(--line); padding: 22px 0 40px; }
.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: var(--ink-soft);
  font-size: 13.5px;
}
.footer-status::before {
  content: '●';
  color: var(--danger);
  margin-right: 6px;
}
.footer-status.live::before { color: var(--green-live); }

/* ---------- chat room view ---------- */
.room-view {
  height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--paper);
}
.room-header {
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 20px;
  border-bottom: 1px solid var(--line);
  background: var(--panel);
}
.room-header-left { display: flex; align-items: center; gap: 12px; }
.room-tag {
  font-family: var(--font-mono);
  font-size: 12.5px;
  color: var(--ink-soft);
  background: var(--paper);
  border: 1px solid var(--line);
  padding: 4px 10px;
  border-radius: 999px;
}

.room-body {
  flex: 1;
  display: grid;
  grid-template-columns: 220px 1fr;
  min-height: 0;
}
.room-sidebar {
  border-right: 1px solid var(--line);
  padding: 20px;
  background: var(--panel);
  overflow-y: auto;
}
.room-sidebar h3 {
  font-size: 12px;
  text-transform: none;
  letter-spacing: 0;
  color: var(--ink-soft);
  margin: 0 0 12px;
  font-weight: 700;
}
.user-list { list-style: none; margin: 0; padding: 0; display: grid; gap: 8px; }
.user-list li {
  font-size: 14px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.user-list li::before {
  content: '';
  width: 7px; height: 7px;
  border-radius: 50%;
  background: var(--green-live);
  flex-shrink: 0;
}

.room-main { display: flex; flex-direction: column; min-height: 0; }
.message-list {
  flex: 1;
  overflow-y: auto;
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.msg {
  max-width: 62ch;
  padding: 10px 14px;
  border-radius: 10px;
  background: var(--panel);
  border: 1px solid var(--line);
  font-size: 14.5px;
}
.msg .msg-meta {
  font-size: 12px;
  color: var(--ink-soft);
  margin-bottom: 3px;
  display: flex;
  gap: 8px;
}
.msg .msg-username { font-weight: 700; color: var(--teal); }
.msg.self { border-color: var(--amber); background: #FFF6EA; align-self: flex-end; }
.msg.system {
  align-self: center;
  background: transparent;
  border: none;
  color: var(--ink-soft);
  font-size: 13px;
  font-style: italic;
}

.message-form {
  display: flex;
  gap: 10px;
  padding: 16px 24px;
  border-top: 1px solid var(--line);
  background: var(--panel);
}
.message-form input {
  flex: 1;
  padding: 12px 14px;
  border-radius: 8px;
  border: 1.5px solid var(--line);
  font-family: var(--font-body);
  font-size: 14.5px;
}
.message-form input:focus { outline: none; border-color: var(--amber-deep); }

/* ---------- responsive ---------- */
@media (max-width: 860px) {
  .hero-grid { grid-template-columns: 1fr; }
  .hero-diagram { order: -1; }
  .join-wrap { grid-template-columns: 1fr; padding: 28px; }
  .room-body { grid-template-columns: 1fr; }
  .room-sidebar { display: none; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .btn { transition: none; }
}