/* OSPRE LNG walkthrough demo. Palette and type follow templates/submission/STYLE-GUIDE.md.
   Gold is an accent only (rules, bars, marker rings), never text. */
:root {
  --navy: #0f2742;
  --gold: #b8932f;
  --ink: #1a1a1a;
  --slate: #4a5568;
  --rule: #c5ccd6;
  --tint: #e9eef5;
  --band: #f5f7fa;
  --gold-tint: #f6efdc;
  --white: #ffffff;
  --font: Arial, "Liberation Sans", Helvetica, sans-serif;
  --focus: 0 0 0 2px var(--white), 0 0 0 5px var(--navy);
  --panel-w: 400px;
}

*, *::before, *::after { box-sizing: border-box; }
html { font-size: 100%; }
body {
  margin: 0;
  font-family: var(--font);
  color: var(--ink);
  background: var(--band);
  line-height: 1.45;
}
a { color: var(--navy); }
a:hover { text-decoration-thickness: 2px; }
:focus-visible { outline: none; box-shadow: var(--focus); border-radius: 3px; }

.visually-hidden {
  position: absolute !important; width: 1px; height: 1px; margin: -1px; padding: 0;
  overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}
.skip-link {
  position: absolute; left: 0.5rem; top: -4rem; z-index: 100;
  background: var(--navy); color: var(--white); padding: 0.6rem 1rem; font-weight: 700;
  border-radius: 0 0 4px 4px;
}
.skip-link:focus { top: 0; }

/* ---------- header / notice / footer ---------- */
.site-header {
  display: flex; align-items: center; gap: 1.25rem; flex-wrap: wrap;
  background: var(--white); padding: 0.75rem 1.25rem;
  border-bottom: 3px solid var(--gold);
}
.logo { display: block; height: 48px; width: auto; }
.titles h1 { margin: 0; font-size: 1.35rem; color: var(--navy); line-height: 1.2; }
.subtitle { margin: 0.15rem 0 0; font-size: 0.9rem; color: var(--slate); }
.notice {
  background: var(--gold-tint); border-left: 5px solid var(--gold);
  padding: 0.5rem 1.25rem; font-size: 0.9rem; color: var(--ink);
}
.site-footer {
  border-top: 1px solid var(--rule); background: var(--white);
  padding: 0.75rem 1.25rem; font-size: 0.8rem; color: var(--slate);
}
.site-footer p { margin: 0.2rem 0; }
.site-footer strong { color: var(--navy); }
.noscript { padding: 1rem; background: var(--white); }

main { display: block; }
main:focus { outline: none; }

/* ---------- toolbar ---------- */
.viewer-section { padding: 0.75rem 1.25rem 0.5rem; }
.toolbar {
  display: flex; flex-wrap: wrap; align-items: center; gap: 0.5rem;
  margin-bottom: 0.6rem;
}
.mode-group { display: inline-flex; border: 1px solid var(--navy); border-radius: 4px; overflow: hidden; }
.mode-group .btn { border: 0; border-radius: 0; }
.mode-group .btn + .btn { border-left: 1px solid var(--navy); }
.btn {
  font: inherit; font-size: 0.9rem; font-weight: 700;
  min-height: 2.25rem; padding: 0.35rem 0.8rem;
  color: var(--navy); background: var(--white);
  border: 1px solid var(--navy); border-radius: 4px; cursor: pointer;
}
.btn:hover { background: var(--tint); }
.btn[aria-pressed="true"] { background: var(--navy); color: var(--white); }
.btn-primary { background: var(--navy); color: var(--white); }
.btn-primary:hover { background: #1c3b5f; }
.btn:disabled { color: var(--slate); border-color: var(--rule); background: var(--band); cursor: not-allowed; }
.btn-icon { display: inline-flex; align-items: center; justify-content: center; width: 2.25rem; padding: 0; }
.select-label { font-size: 0.9rem; font-weight: 700; color: var(--navy); margin-left: 0.25rem; }
.select {
  font: inherit; font-size: 0.9rem; min-height: 2.25rem; padding: 0.25rem 0.5rem;
  border: 1px solid var(--navy); border-radius: 4px; background: var(--white); color: var(--ink);
  max-width: 20rem;
}

/* ---------- stage: viewer + panel ---------- */
.stage {
  display: flex; gap: 0; min-height: 420px; height: min(68vh, 760px);
  border: 1px solid var(--rule); background: var(--white);
}
.viewer-wrap { position: relative; flex: 1 1 auto; min-width: 0; overflow: hidden; background: #dfe6ee; }
.viewer { position: absolute; inset: 0; touch-action: none; }
.viewer:focus-visible { box-shadow: inset 0 0 0 3px var(--navy), inset 0 0 0 6px var(--white); border-radius: 0; }
.viewer canvas { display: block; width: 100%; height: 100%; }
.viewer.walk { cursor: crosshair; }

.hotspot-layer { position: absolute; inset: 0; pointer-events: none; }
.hotspot {
  position: absolute; left: 0; top: 0; pointer-events: auto;
  transform: translate(-50%, -100%);
  display: inline-flex; align-items: center; gap: 0.35rem;
  font: inherit; font-size: 0.8rem; font-weight: 700; line-height: 1;
  padding: 0.3rem 0.55rem 0.3rem 0.3rem; min-height: 1.9rem;
  color: var(--white); background: var(--navy);
  border: 2px solid var(--white); border-radius: 999px;
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.45);
  cursor: pointer; white-space: nowrap;
}
.hotspot::after { /* pointer stem down to the anchor */
  content: ""; position: absolute; left: 50%; bottom: -8px; width: 2px; height: 7px;
  background: var(--white); transform: translateX(-50%);
}
.hotspot .dot {
  width: 1.1rem; height: 1.1rem; border-radius: 50%;
  background: var(--navy); border: 3px solid var(--gold); flex: none;
}
.hotspot:hover { background: #1c3b5f; }
.hotspot:focus-visible { box-shadow: 0 0 0 3px var(--navy), 0 0 0 6px var(--white); border-radius: 999px; }
.hotspot.active { background: var(--white); color: var(--navy); border-color: var(--navy); }
.hotspot.active .dot { background: var(--gold); border-color: var(--navy); }
.hotspot.compact:not(:hover):not(:focus-visible):not(.active) { padding: 0.3rem; gap: 0; }
.hotspot.compact:not(:hover):not(:focus-visible):not(.active) .label { display: none; }
.hotspot[hidden] { display: none; }
.hotspot:not(.compact) { z-index: 1; }
.hotspot.group .count {
  min-width: 1.15rem; padding: 0.1rem 0.25rem; border-radius: 999px; text-align: center;
  font-size: 0.7rem; background: var(--white); color: var(--navy);
}
.hotspot.group.compact:not(:hover):not(:focus-visible):not(.active) .count { display: none; }
.hotspot:hover, .hotspot:focus-visible, .hotspot.active { z-index: 2; }

.mode-badge {
  position: absolute; left: 0.75rem; bottom: 0.75rem;
  background: rgba(15, 39, 66, 0.92); color: var(--white);
  font-size: 0.8rem; font-weight: 700; padding: 0.3rem 0.6rem; border-radius: 4px;
  pointer-events: none;
}
.crosshair { position: absolute; left: 50%; top: 50%; width: 14px; height: 14px; margin: -7px 0 0 -7px; pointer-events: none; }
.crosshair::before, .crosshair::after { content: ""; position: absolute; background: var(--white); box-shadow: 0 0 0 1px var(--navy); }
.crosshair::before { left: 6px; top: 0; width: 2px; height: 14px; }
.crosshair::after { top: 6px; left: 0; height: 2px; width: 14px; }

.loading, .viewer-status {
  position: absolute; left: 50%; top: 50%; transform: translate(-50%, -50%);
  background: var(--white); color: var(--ink); border: 1px solid var(--rule); border-left: 5px solid var(--navy);
  padding: 0.9rem 1.1rem; border-radius: 4px; max-width: min(34rem, 90%);
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.15); font-size: 0.95rem;
}
.loading { display: flex; align-items: center; gap: 0.6rem; }
.loading[hidden], .viewer-status[hidden] { display: none; }
.viewer-status h3 { margin: 0 0 0.4rem; color: var(--navy); font-size: 1.05rem; }
.viewer-status p { margin: 0.3rem 0; }
.spinner {
  width: 1.2rem; height: 1.2rem; border-radius: 50%;
  border: 3px solid var(--tint); border-top-color: var(--navy);
  animation: spin 0.9s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }
.poster { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; }

/* ---------- details panel ---------- */
.panel {
  flex: 0 0 var(--panel-w); width: var(--panel-w); max-width: 100%;
  display: flex; flex-direction: column; min-height: 0;
  border-left: 1px solid var(--rule); background: var(--white);
}
.panel[hidden] { display: none; }
.panel-head {
  display: grid; grid-template-columns: 1fr auto; column-gap: 0.5rem; align-items: start;
  padding: 0.8rem 1rem 0.6rem; border-bottom: 1px solid var(--gold);
}
.panel-kicker { grid-column: 1; margin: 0; font-size: 0.8rem; font-weight: 700; color: var(--slate); text-transform: uppercase; letter-spacing: 0.04em; }
.panel-title { grid-column: 1; margin: 0.1rem 0 0; font-size: 1.2rem; color: var(--navy); line-height: 1.25; }
.panel-title:focus { outline: none; }
.panel-title:focus-visible { box-shadow: var(--focus); }
#panel-close { grid-column: 2; grid-row: 1 / span 2; }
.panel-body { flex: 1 1 auto; overflow-y: auto; padding: 0.8rem 1rem 1rem; font-size: 0.95rem; }
.panel-body h3 { font-size: 1rem; color: var(--navy); margin: 1rem 0 0.35rem; }
.panel-body h3:first-child { margin-top: 0; }
.panel-body ul { margin: 0.2rem 0 0.4rem; padding-left: 1.2rem; }
.panel-body li { margin-bottom: 0.35rem; }
.meta {
  display: grid; grid-template-columns: auto 1fr; gap: 0.15rem 0.6rem; margin: 0 0 0.6rem;
  font-size: 0.85rem; background: var(--tint); padding: 0.5rem 0.6rem; border-radius: 3px;
}
.meta dt { font-weight: 700; color: var(--navy); }
.meta dd { margin: 0; }
.cites { list-style: none; padding-left: 0 !important; }
.cites li { border-left: 4px solid var(--gold); padding: 0.1rem 0 0.1rem 0.55rem; }
.cite-sub { display: block; font-size: 0.8rem; color: var(--slate); }
.cite-note { display: block; font-size: 0.85rem; color: var(--ink); }
.illustrative { font-size: 0.8rem; color: var(--slate); border-top: 1px solid var(--rule); padding-top: 0.5rem; margin-top: 1rem; }
.stop-intro { background: var(--band); border-left: 4px solid var(--navy); padding: 0.5rem 0.65rem; margin: 0 0 0.75rem; }
.panel-body .stop-entries { display: flex; flex-wrap: wrap; gap: 0.35rem; margin: 0 0 0.75rem; padding: 0; list-style: none; }
.stop-entries .btn { font-size: 0.8rem; min-height: 2rem; padding: 0.25rem 0.55rem; }

.tour-progress { padding: 0.55rem 1rem 0.25rem; background: var(--band); border-bottom: 1px solid var(--rule); }
.tour-count { margin: 0 0 0.35rem; font-weight: 700; color: var(--navy); font-size: 0.9rem; }
.progress-track { height: 6px; background: var(--tint); border-radius: 3px; overflow: hidden; border: 1px solid var(--rule); }
.progress-bar { height: 100%; width: 0; background: var(--navy); transition: width 0.3s ease; }
.tour-nav { display: flex; gap: 0.4rem; flex-wrap: wrap; padding: 0.6rem 1rem; border-top: 1px solid var(--rule); background: var(--band); }
.tour-nav[hidden], .tour-progress[hidden] { display: none; }

/* ---------- on-screen pad ---------- */
.nav-pad { margin-top: 0.5rem; }
.pad { display: flex; flex-wrap: wrap; gap: 0.35rem; }
.pad[hidden] { display: none; }
.btn-pad { font-size: 0.8rem; min-height: 2rem; padding: 0.25rem 0.6rem; }
.instructions { font-size: 0.85rem; color: var(--slate); margin: 0.5rem 0 0; max-width: 70rem; }
.instructions [hidden] { display: none; }

/* ---------- text alternative ---------- */
.text-alt { padding: 1rem 1.25rem 1.5rem; max-width: 72rem; }
.text-alt:focus { outline: none; }
.text-alt > h2 { color: var(--navy); font-size: 1.3rem; margin: 0.5rem 0 0.4rem; padding-bottom: 0.3rem; border-bottom: 1px solid var(--gold); }
.text-alt h3 { color: var(--navy); font-size: 1.1rem; margin: 1.25rem 0 0.4rem; }
.text-alt h4 { color: var(--navy); font-size: 1rem; margin: 0.8rem 0 0.3rem; }
.ta-stop { background: var(--white); border: 1px solid var(--rule); border-radius: 4px; padding: 0.25rem 1rem 0.75rem; margin: 0.75rem 0; }
.ta-entry { border-top: 1px solid var(--rule); padding-top: 0.25rem; margin-top: 0.75rem; }
.ta-entry:first-of-type { border-top: 0; }
.ta-entry ul { padding-left: 1.2rem; }
.ta-entry li { margin-bottom: 0.3rem; }
.ta-actions { margin: 0.35rem 0; }

/* ---------- help dialog ---------- */
.help-dialog {
  border: 1px solid var(--rule); border-top: 4px solid var(--navy); border-radius: 4px;
  padding: 1rem 1.25rem; max-width: 36rem; width: calc(100% - 2rem); color: var(--ink);
}
.help-dialog::backdrop { background: rgba(15, 39, 66, 0.45); }
.help-dialog h2 { margin: 0 0 0.4rem; color: var(--navy); font-size: 1.2rem; }
.help-dialog table { border-collapse: collapse; width: 100%; font-size: 0.9rem; margin: 0.5rem 0 0.9rem; }
.help-dialog caption { text-align: left; font-weight: 700; color: var(--navy); font-size: 0.85rem; padding-bottom: 0.3rem; }
.help-dialog th { background: var(--navy); color: var(--white); text-align: left; padding: 0.3rem 0.5rem; }
.help-dialog td { border: 1px solid var(--rule); padding: 0.3rem 0.5rem; vertical-align: top; }
.help-dialog tbody tr:nth-child(even) td { background: var(--band); }
kbd {
  font-family: var(--font); font-size: 0.85em; font-weight: 700;
  background: var(--tint); border: 1px solid var(--rule); border-radius: 3px; padding: 0 0.3rem;
}

/* ---------- responsive ---------- */
@media (max-width: 900px) {
  .stage { flex-direction: column; height: auto; }
  .viewer-wrap { height: 60vh; min-height: 320px; flex: none; }
  .panel { flex: none; width: 100%; border-left: 0; border-top: 1px solid var(--rule); max-height: none; }
}

@media (prefers-reduced-motion: reduce) {
  .spinner { animation-duration: 3s; }
  .progress-bar { transition: none; }
}

@media (forced-colors: active) {
  .hotspot, .btn { border: 2px solid ButtonText; }
  .hotspot .dot { forced-color-adjust: none; }
}

/* ---------- concept prototype banner (persistent) ---------- */
.proto-banner {
  position: sticky; top: 0; z-index: 50;
  padding: 0.3rem 1rem; text-align: center;
  font-size: 0.85rem; font-weight: 700; letter-spacing: 0.02em;
  color: var(--white); background: var(--navy); border-bottom: 2px solid var(--gold);
}