:root {
  --bg: #f5f7fa;
  --surface: #ffffff;
  --surface-2: #eef3f6;
  --ink: #17212b;
  --muted: #5a6877;
  --line: #d7dee6;
  --line-strong: #a8b5c1;
  --blue: #195a8f;
  --green: #24745a;
  --amber: #8a5b12;
  --red: #9d3f32;
  --shadow: 0 18px 45px rgba(23, 33, 43, 0.08);
  --radius: 8px;
  --space-1: 0.35rem;
  --space-2: 0.7rem;
  --space-3: 1rem;
  --space-4: 1.5rem;
  --space-5: 2.25rem;
  --space-6: 3.5rem;
  --font: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #10161d;
    --surface: #161f28;
    --surface-2: #1d2a35;
    --ink: #edf3f8;
    --muted: #aab7c3;
    --line: #2e3d4b;
    --line-strong: #526373;
    --blue: #78b7e6;
    --green: #80c7ad;
    --amber: #d9a64a;
    --red: #e08b7c;
    --shadow: 0 18px 45px rgba(0, 0, 0, 0.28);
  }
}

* {
  box-sizing: border-box;
}

html {
  background: var(--bg);
  color: var(--ink);
  scroll-behavior: smooth;
}

body {
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.55 var(--font);
  margin: 0;
  min-width: 320px;
  overflow-x: hidden;
  text-rendering: optimizeLegibility;
}

body::before {
  background:
    linear-gradient(90deg, rgba(25, 90, 143, 0.07) 1px, transparent 1px),
    linear-gradient(180deg, rgba(36, 116, 90, 0.06) 1px, transparent 1px);
  background-size: 72px 72px;
  content: "";
  inset: 0;
  opacity: 0.55;
  pointer-events: none;
  position: fixed;
  z-index: -1;
}

a {
  color: var(--blue);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

p {
  margin: 0 0 var(--space-3);
}

h1,
h2,
h3 {
  color: var(--ink);
  letter-spacing: 0;
  line-height: 1.05;
  margin: 0;
}

h1 {
  font-size: clamp(2.45rem, 6.2vw, 4.8rem);
  max-width: 13.5ch;
}

h2 {
  font-size: clamp(1.7rem, 4vw, 2.8rem);
}

h3 {
  font-size: 1.05rem;
}

ul {
  margin: 0;
  padding-left: 1.2rem;
}

.site-shell {
  margin: 0 auto;
  max-width: 1240px;
  padding: var(--space-4);
}

.site-header {
  align-items: center;
  display: grid;
  gap: var(--space-4);
  grid-template-columns: minmax(220px, 1fr) auto;
  padding: var(--space-3) 0 var(--space-5);
}

.site-brand {
  max-width: 760px;
  min-width: 0;
}

.site-title {
  color: var(--ink);
  display: inline-flex;
  font-size: 0.95rem;
  font-weight: 800;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.site-title:hover {
  text-decoration: none;
}

.site-brand p {
  color: var(--muted);
  font-size: 0.92rem;
  margin: var(--space-1) 0 0;
  max-width: 78ch;
  overflow-wrap: break-word;
}

.main-nav ul,
.site-footer nav,
.command-actions,
.signal-row,
.system-card__stack,
.system-card__links,
.project-filters {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  list-style: none;
  margin: 0;
  padding: 0;
}

.main-nav {
  min-width: 0;
}

.main-nav a,
.site-footer a,
.filter-btn,
.signal-row span,
.system-card__stack span,
.system-card__category,
.system-card__status,
.system-lane__category {
  align-items: center;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--muted);
  display: inline-flex;
  font-size: 0.82rem;
  line-height: 1;
  min-height: 34px;
  padding: 0.52rem 0.75rem;
}

.main-nav a:hover,
.site-footer a:hover,
.filter-btn:hover,
.filter-btn.active {
  border-color: var(--line-strong);
  color: var(--ink);
  text-decoration: none;
}

.site-main {
  min-height: 65vh;
}

.command-hero,
.command-header {
  border-top: 4px solid var(--ink);
  display: grid;
  gap: var(--space-4);
  grid-template-columns: minmax(0, 1fr);
  margin-bottom: var(--space-6);
  max-width: 1040px;
  min-width: 0;
  padding-top: var(--space-5);
}

.command-header {
  max-width: 900px;
}

.command-hero .command-lede,
.command-header .command-lede {
  align-self: start;
}

.command-eyebrow,
.section-kicker {
  color: var(--green);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  margin-bottom: var(--space-2);
  text-transform: uppercase;
}

.command-lede {
  color: var(--muted);
  font-size: clamp(1.05rem, 2vw, 1.28rem);
  max-width: 70ch;
  overflow-wrap: break-word;
}

.command-actions {
  margin-top: var(--space-4);
}

.btn {
  border: 1px solid var(--line-strong);
  border-radius: var(--radius);
  display: inline-flex;
  font-weight: 800;
  justify-content: center;
  line-height: 1;
  min-height: 44px;
  padding: 0.85rem 1rem;
  text-decoration: none;
}

.btn-primary,
.btn:not(.btn-outline) {
  background: var(--ink);
  border-color: var(--ink);
  color: var(--surface);
}

.btn-outline {
  background: transparent;
  color: var(--ink);
}

.btn:hover {
  box-shadow: var(--shadow);
  text-decoration: none;
}

.signal-row {
  margin-top: var(--space-4);
}

.signal-row span {
  max-width: 100%;
}

.signal-row span:nth-child(3n + 1),
.system-card__category,
.system-lane__category {
  color: var(--blue);
}

.signal-row span:nth-child(3n + 2),
.system-card__status {
  color: var(--green);
}

.signal-row span:nth-child(3n) {
  color: var(--amber);
}

.command-section {
  border-top: 1px solid var(--line);
  margin-bottom: var(--space-6);
  padding-top: var(--space-5);
}

.command-section > h2,
.command-section > .section-kicker + h2 {
  margin-bottom: var(--space-4);
  max-width: 900px;
}

.systems-grid,
.lane-summary-grid,
.proof-grid,
.audience-grid,
.system-lane__grid {
  display: grid;
  gap: var(--space-3);
}

.systems-grid {
  grid-template-columns: repeat(auto-fit, minmax(290px, 1fr));
}

.systems-grid--featured {
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

.lane-summary-grid,
.proof-grid,
.audience-grid,
.system-lane__grid {
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
}

.system-card,
.lane-summary,
.proof-grid > div,
.audience-grid > div,
.notes-panel {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.system-card {
  display: flex;
  flex-direction: column;
  min-height: 100%;
  padding: var(--space-4);
}

.system-card__meta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  margin-bottom: var(--space-3);
}

.system-card__title {
  margin-bottom: var(--space-2);
}

.system-card__summary,
.lane-summary small,
.proof-grid span,
.audience-grid span,
.system-card__proof dd,
.system-lane p {
  color: var(--muted);
}

.system-card__proof {
  border-top: 1px solid var(--line);
  margin: var(--space-3) 0;
  padding-top: var(--space-3);
}

.system-card__proof dt {
  color: var(--ink);
  font-weight: 800;
}

.system-card__proof dd {
  margin: 0 0 var(--space-2);
}

.system-card__links {
  margin-top: auto;
  padding-top: var(--space-3);
}

.system-card__evidence {
  border-top: 1px solid var(--line);
  margin-bottom: var(--space-3);
  padding-top: var(--space-3);
}

.system-card__evidence strong {
  display: block;
  font-size: 0.82rem;
  letter-spacing: 0.06em;
  margin-bottom: var(--space-2);
  text-transform: uppercase;
}

.system-card__evidence ul {
  display: grid;
  gap: var(--space-2);
  padding-left: 1rem;
}

.system-card__evidence li,
.evidence-strip span {
  color: var(--muted);
  font-size: 0.92rem;
}

.system-card__links a {
  color: var(--blue);
  font-weight: 800;
}

.lane-summary {
  color: var(--ink);
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  padding: var(--space-4);
}

.lane-summary:hover {
  border-color: var(--line-strong);
  text-decoration: none;
}

.lane-summary span {
  color: var(--blue);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.system-lane {
  border-top: 1px solid var(--line);
  margin-top: var(--space-5);
  padding-top: var(--space-4);
}

.system-lane:first-of-type {
  margin-top: 0;
}

.system-lane__header {
  margin-bottom: var(--space-3);
}

.system-lane__header h2 {
  margin-top: var(--space-2);
}

.system-lane__grid > div,
.principles-panel {
  background: var(--surface-2);
  border-left: 4px solid var(--line-strong);
  border-radius: var(--radius);
  padding: var(--space-4);
}

.system-lane__grid h3 {
  color: var(--ink);
  margin-bottom: var(--space-2);
}

.evidence-strip {
  display: grid;
  gap: var(--space-2);
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  margin-top: var(--space-3);
}

.evidence-strip span {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: var(--space-3);
}

.proof-grid > div,
.audience-grid > div,
.notes-panel,
.principles-panel {
  padding: var(--space-4);
}

.intake-form {
  display: grid;
  gap: var(--space-3);
  grid-template-columns: repeat(2, minmax(0, 1fr));
  max-width: 920px;
}

.intake-form label {
  color: var(--ink);
  display: block;
  font-size: 0.82rem;
  font-weight: 800;
  margin-bottom: var(--space-1);
}

.intake-form input,
.intake-form select,
.intake-form textarea {
  background: var(--surface);
  border: 1px solid var(--line-strong);
  border-radius: var(--radius);
  color: var(--ink);
  font: inherit;
  min-height: 44px;
  padding: 0.75rem;
  width: 100%;
}

.intake-form textarea {
  min-height: 120px;
  resize: vertical;
}

.intake-form__wide {
  grid-column: 1 / -1;
}

.proof-grid strong,
.audience-grid strong {
  display: block;
  margin-bottom: var(--space-1);
}

.project-filters {
  margin-bottom: var(--space-4);
}

.filter-btn {
  background: var(--surface);
  cursor: pointer;
  font: inherit;
}

.notes-panel + .notes-panel {
  margin-top: var(--space-3);
}

.principles-panel {
  box-shadow: none;
}

.site-footer {
  align-items: center;
  border-top: 1px solid var(--line);
  color: var(--muted);
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
  justify-content: space-between;
  margin-top: var(--space-6);
  padding: var(--space-4) 0 var(--space-3);
}

.site-footer div {
  display: grid;
  gap: var(--space-1);
}

.site-footer strong {
  color: var(--ink);
}

@media (max-width: 860px) {
  .site-header,
  .command-hero {
    grid-template-columns: 1fr;
  }

  .site-header {
    align-items: start;
  }
}

@media (max-width: 560px) {
  .site-shell {
    padding: var(--space-3);
  }

  h1 {
    font-size: clamp(2.25rem, 13vw, 3.1rem);
    max-width: 10.8ch;
  }

  .command-hero,
  .command-header,
  .command-section {
    margin-bottom: var(--space-5);
  }

  .command-actions .btn,
  .main-nav a {
    width: 100%;
  }

  .main-nav li {
    flex: 1 1 46%;
  }

  .systems-grid,
  .lane-summary-grid,
  .proof-grid,
  .audience-grid,
  .system-lane__grid,
  .intake-form {
    grid-template-columns: 1fr;
  }
}