:root {
  --bg: #f4f7fb;
  --bg-tint: #eaf2f8;
  --surface: #ffffff;
  --surface-alt: #f8fbfe;
  --text: #173047;
  --text-soft: #607387;
  --line: #d7e2ed;
  --line-strong: #bcd0e2;
  --brand: #0e5ea7;
  --brand-dark: #0a3559;
  --brand-soft: #deecfb;
  --hero-top: #103f6a;
  --hero-bottom: #126592;
  --shadow: 0 12px 28px rgba(16, 39, 63, 0.08);
  --radius: 18px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}
code {
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
  background: #eef4fb;
  color: var(--brand-dark);
  border-radius: 8px;
  padding: 0.1rem 0.38rem;
  white-space: nowrap;
}

.platform-shell {
  width: min(1180px, calc(100% - 40px));
  margin: 0 auto;
}

.platform-topbar {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(18, 40, 60, 0.95);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  backdrop-filter: blur(12px);
}
.platform-topbar-inner {
  min-height: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}
.platform-brand {
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
  color: #fff;
  text-decoration: none;
  font-weight: 800;
}
.platform-logo {
  width: 34px;
  height: 34px;
  object-fit: cover;
  border-radius: 999px;
  border: 1px solid rgba(255, 255, 255, 0.18);
}
.platform-nav {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.9rem 1rem;
}
.platform-nav-group {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
}
.platform-nav-group a {
  text-decoration: none;
  font-size: 0.84rem;
  font-weight: 700;
}
.platform-nav-group-local a {
  color: #91d5ff;
  background: rgba(28, 92, 136, 0.4);
  border: 1px solid rgba(145, 213, 255, 0.22);
  padding: 0.26rem 0.62rem;
  border-radius: 999px;
}
.platform-nav-group-local a:hover,
.platform-nav-group-local a:focus-visible {
  color: #dff3ff;
  background: rgba(39, 112, 162, 0.6);
}
.platform-nav-group-global a {
  color: rgba(255, 255, 255, 0.92);
  padding: 0.22rem 0.1rem;
}
.platform-nav-group-global a:hover,
.platform-nav-group-global a:focus-visible {
  color: #fff;
}

.platform-page { padding-bottom: 56px; }
.platform-hero {
  padding: 56px 0 76px;
  background: linear-gradient(180deg, var(--hero-top) 0%, var(--hero-bottom) 100%);
}
.platform-hero-inner { text-align: center; }
.platform-kicker {
  margin: 0 0 12px;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-size: 0.76rem;
  font-weight: 800;
  color: #8ec9ff;
}
.platform-hero h1 {
  max-width: 760px;
  margin: 0 auto;
  color: #fff;
  font-size: clamp(2.05rem, 3.5vw, 3.05rem);
  line-height: 1.06;
  letter-spacing: -0.04em;
}
.platform-hero-copy {
  max-width: 820px;
  margin: 18px auto 0;
  color: rgba(240, 247, 255, 0.92);
}
.platform-hero-actions {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0.8rem;
  margin-top: 24px;
}
.platform-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 42px;
  padding: 0 16px;
  border-radius: 999px;
  border: 1px solid rgba(255, 255, 255, 0.18);
  background: rgba(255, 255, 255, 0.08);
  color: #fff;
  text-decoration: none;
  font-weight: 700;
  cursor: pointer;
}
.platform-button:hover,
.platform-button:focus-visible { background: rgba(255, 255, 255, 0.14); }
.platform-button-primary {
  background: #25bfdf;
  border-color: transparent;
  color: #062a46;
}
.platform-button-primary:hover,
.platform-button-primary:focus-visible { background: #44cae6; }
.platform-button-small {
  min-height: 34px;
  padding-inline: 12px;
  font-size: 0.88rem;
  border-color: var(--line);
  background: #fff;
  color: var(--brand);
}

.platform-section { padding: 42px 0; }
.platform-section-overlap { margin-top: -30px; }
.platform-section-tinted { background: var(--bg-tint); }
.platform-section-head { margin-bottom: 24px; }
.platform-section-head h2 {
  margin: 0;
  font-size: clamp(1.8rem, 2.5vw, 2.35rem);
  line-height: 1.1;
  letter-spacing: -0.03em;
}
.platform-section-head p:last-child {
  max-width: none;
  margin: 10px 0 0;
  color: var(--text-soft);
}

.platform-card-grid { display: grid; gap: 16px; }
.platform-card-grid-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.platform-card-grid-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.platform-card-grid-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.platform-card-grid-resolution { grid-template-columns: minmax(0, 1.4fr) minmax(280px, 0.8fr); }
.platform-card-grid-1 { grid-template-columns: 1fr; }
.platform-card,
.platform-panel,
.platform-explorer-card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}
.platform-card { padding: 20px; }
.platform-card h3,
.platform-panel h3 { margin: 0 0 8px; font-size: 1.06rem; }
.platform-card p,
.platform-card li,
.platform-panel p,
.platform-panel li { color: var(--text-soft); }
.platform-card-accent { background: var(--surface-alt); }
.platform-step {
  display: inline-flex;
  width: 30px;
  height: 30px;
  align-items: center;
  justify-content: center;
  margin-bottom: 12px;
  border-radius: 999px;
  background: var(--brand-soft);
  color: var(--brand);
  font-size: 0.78rem;
  font-weight: 800;
}

.platform-explorer-card { padding: 20px; }
.platform-explorer-top {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}
.platform-panel { padding: 20px; }
.platform-explorer-top > .platform-panel:first-child {
  padding: 16px;
}
.platform-controls-panel { order: 2; }
.platform-map-panel { margin-top: 16px; }
.platform-panel-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 16px;
}
.platform-panel-head h3,
.platform-panel-head p { margin: 0; }
.platform-panel-head-stack { justify-content: flex-start; }
.platform-subnote,
.platform-note {
  font-size: 0.93rem;
  color: var(--text-soft);
}
.platform-note {
  margin: 16px 0 0;
  padding: 12px 14px;
  border-radius: 14px;
  background: var(--surface-alt);
  border: 1px solid var(--line);
}
.platform-control-grid {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 12px;
}
.platform-field span:first-child,
.platform-range-head span:first-child {
  display: block;
  margin-bottom: 6px;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--text);
}
.platform-select {
  width: 100%;
  min-height: 42px;
  padding: 0 12px;
  border-radius: 12px;
  border: 1px solid var(--line);
  background: #fff;
  color: var(--text);
  font: inherit;
}
.platform-range-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
  margin-top: 16px;
}
.platform-range-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
}
.platform-range-value {
  color: var(--brand);
  font-size: 0.84rem;
  font-weight: 700;
}
.platform-range { width: 100%; margin-top: 8px; }
.platform-stat-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 8px;
}
.platform-stat {
  padding: 9px 10px;
  border-radius: 12px;
  background: var(--surface-alt);
  border: 1px solid var(--line);
}
.platform-stat-k {
  display: block;
  font-size: 0.68rem;
  font-weight: 800;
  letter-spacing: 0.03em;
  text-transform: uppercase;
  color: var(--text-soft);
}
.platform-stat-v {
  display: block;
  margin-top: 3px;
  font-size: 0.94rem;
  font-weight: 800;
  color: var(--text);
}
.platform-panel-head-map { align-items: flex-start; }
.platform-panel-head-map > div:first-child {
  flex: 1;
  min-width: 0;
}
.platform-legend {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 10px 14px;
}
.legend-item {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--text-soft);
  font-size: 0.85rem;
}
.legend-swatch {
  width: 14px;
  height: 14px;
  border-radius: 999px;
  display: inline-block;
}
.legend-land { background: #d7cfb8; border: 1px solid #b4aa8b; }
.legend-speed { background: linear-gradient(135deg, #102f4c, #11bfe4 60%, #ffe289); }
.legend-current { background: #ebf7ff; border: 1px solid rgba(176, 206, 232, 0.9); }
.legend-bathy { background: linear-gradient(135deg, #1a3e5d, #5b88aa, #c3dcef); }
.platform-map-shell {
  margin-top: 14px;
  overflow: hidden;
  border-radius: 18px;
  border: 1px solid var(--line-strong);
  background: linear-gradient(180deg, #b9d5e6 0%, #436b8e 40%, #112e49 100%);
}
.platform-map-shell-large {
  height: min(68vh, 760px);
  min-height: 500px;
}
#flowFieldMap {
  display: block;
  width: 100%;
  height: 100%;
  border-radius: 10px;
}
#flowFieldMap .leaflet-control-zoom {
  border: 1px solid rgba(20, 62, 96, 0.35);
}
#flowFieldMap .leaflet-control-zoom a {
  color: #244a69;
}
.platform-meta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 14px;
}
.platform-meta-pill {
  display: inline-flex;
  align-items: center;
  padding: 8px 12px;
  border-radius: 999px;
  background: #edf5ff;
  color: var(--brand);
  font-size: 0.84rem;
  font-weight: 700;
}
.platform-table-wrap {
  overflow-x: auto;
  border: 1px solid var(--line);
  border-radius: 14px;
}
.platform-table {
  width: 100%;
  min-width: 620px;
  border-collapse: collapse;
}
.platform-table thead { background: var(--brand-dark); }
.platform-table th,
.platform-table td {
  padding: 12px 10px;
  border-bottom: 1px solid #e6edf5;
  text-align: left;
  font-size: 0.9rem;
}
.platform-table th { color: #fff; font-weight: 800; }
.platform-table td { color: var(--text-soft); }
.platform-list { margin: 0; padding-left: 18px; }
.platform-list li + li { margin-top: 10px; }
.platform-list-tight li + li { margin-top: 6px; }
.platform-code {
  margin: 12px 0;
  padding: 14px;
  overflow-x: auto;
  border-radius: 14px;
  background: #0c1f31;
  color: #e7f2ff;
  font-size: 0.87rem;
  line-height: 1.55;
}
.platform-code code {
  background: transparent;
  color: inherit;
  padding: 0;
  white-space: pre;
}
.platform-code-wrap {
  position: relative;
}
.platform-copy-btn {
  position: absolute;
  top: 18px;
  right: 12px;
  z-index: 2;
  min-height: 28px;
  border: 1px solid rgba(210, 210, 210, 0.5);
  border-radius: 8px;
  background: rgba(220, 220, 220, 0.5);
  color: #243447;
  font-size: 0.78rem;
  font-weight: 700;
  padding: 0 9px;
  cursor: pointer;
}
.platform-copy-btn:hover,
.platform-copy-btn:focus-visible {
  background: rgba(210, 210, 210, 0.65);
}
.platform-banner {
  margin-top: 16px;
  padding: 14px 16px;
  border-radius: 16px;
  background: var(--surface);
  border: 1px solid var(--line);
  color: var(--text-soft);
}
.platform-detail-grid { margin-top: 16px; }
.platform-precision-grid {
  display: grid;
  gap: 12px;
  grid-template-columns: repeat(4, minmax(0, 1fr));
}
.platform-precision-item {
  border: 1px solid var(--line);
  background: var(--surface-alt);
  border-radius: 12px;
  padding: 12px;
}
.platform-precision-k {
  display: block;
  font-size: 0.75rem;
  font-weight: 800;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--text-soft);
}
.platform-precision-v {
  display: block;
  margin-top: 6px;
  font-size: 1rem;
  font-weight: 800;
  color: var(--text);
}
.platform-source-grid {
  display: grid;
  grid-template-columns: minmax(180px, 0.9fr) minmax(260px, 1.15fr) minmax(320px, 1.25fr);
  border: 1px solid var(--line);
  border-radius: 14px;
  overflow: hidden;
}
.platform-source-cell {
  padding: 11px 13px;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  font-size: 0.9rem;
  color: var(--text);
}
.platform-source-grid .platform-source-cell:nth-child(3n) { border-right: none; }
.platform-source-grid .platform-source-cell:nth-last-child(-n + 3) { border-bottom: none; }
.platform-source-head {
  background: #eef3f8;
  font-weight: 700;
  color: #173a5c;
}
.platform-source-note { margin-top: 12px; }

@media (max-width: 1120px) {
  .platform-card-grid-4,
  .platform-card-grid-resolution,
  .platform-precision-grid,
  .platform-control-grid,
  .platform-range-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .platform-source-grid { grid-template-columns: 1fr; }
  .platform-source-grid .platform-source-cell {
    border-right: none;
    border-bottom: 1px solid var(--line);
  }
  .platform-source-grid .platform-source-cell:last-child { border-bottom: none; }
  .platform-explorer-top { grid-template-columns: 1fr; }
}
@media (max-width: 860px) {
  .platform-shell { width: min(100% - 24px, 1180px); }
  .platform-topbar-inner,
  .platform-panel-head,
  .platform-panel-head-map { flex-direction: column; align-items: flex-start; }
  .platform-nav { align-items: flex-start; }
  .platform-card-grid-2,
  .platform-card-grid-3,
  .platform-card-grid-4,
  .platform-card-grid-resolution,
  .platform-precision-grid,
  .platform-control-grid,
  .platform-range-grid { grid-template-columns: 1fr; }
  .platform-stat-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .platform-legend { justify-content: flex-start; }
  .platform-hero { padding-top: 40px; }
  .platform-hero-inner,
  .platform-hero h1,
  .platform-hero-copy { text-align: left; }
  .platform-hero-actions { justify-content: flex-start; }
  .platform-section-overlap { margin-top: -18px; }
  .platform-map-shell-large { min-height: 360px; }
}