/* ============================================================
   SenseMakingLens — Design System
   Premium editorial / intellectual publication
   Palette: warm parchment surfaces, deep ink-navy, oxblood accent
   ============================================================ */

:root,
[data-theme='light'] {
  /* Type scale */
  --text-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.8125rem);
  --text-sm: clamp(0.8125rem, 0.78rem + 0.2vw, 0.9375rem);
  --text-base: clamp(1rem, 0.96rem + 0.2vw, 1.0625rem);
  --text-lg: clamp(1.1875rem, 1.05rem + 0.6vw, 1.4375rem);
  --text-xl: clamp(1.5rem, 1.2rem + 1.25vw, 2.125rem);
  --text-2xl: clamp(2.1rem, 1.4rem + 2.6vw, 3.4rem);
  --text-3xl: clamp(2.6rem, 1.2rem + 4vw, 4.75rem);
  --text-hero: clamp(2.9rem, 1rem + 6.2vw, 6.5rem);

  /* Spacing */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-32: 8rem;

  /* Surfaces — warm parchment / ivory */
  --color-bg: #f4f0e6;
  --color-surface: #f8f5ec;
  --color-surface-2: #fbf9f2;
  --color-surface-offset: #ece6d7;
  --color-surface-dynamic: #e3dccb;
  --color-divider: #d8d0bd;
  --color-border: #cbc2ac;

  /* Text — deep ink */
  --color-text: #1c2433;
  --color-text-muted: #5a5f63;
  --color-text-faint: #908a7a;
  --color-text-inverse: #f6f2e8;

  /* Primary — deep ink navy */
  --color-primary: #1d3354;
  --color-primary-hover: #14253f;
  --color-primary-active: #0d1929;
  --color-primary-highlight: #d3d6dd;

  /* Accent — oxblood */
  --color-accent: #7a2230;
  --color-accent-hover: #5f1925;
  --color-accent-active: #44111a;

  --radius-sm: 0.25rem;
  --radius-md: 0.375rem;
  --radius-lg: 0.625rem;
  --radius-xl: 1rem;
  --radius-full: 9999px;

  --transition-interactive: 220ms cubic-bezier(0.16, 1, 0.3, 1);

  --shadow-sm: 0 1px 2px oklch(0.25 0.03 260 / 0.07);
  --shadow-md: 0 6px 20px oklch(0.25 0.03 260 / 0.09);
  --shadow-lg: 0 18px 48px oklch(0.2 0.04 260 / 0.16);

  --content-narrow: 660px;
  --content-prose: 720px;
  --content-default: 1000px;
  --content-wide: 1240px;

  --font-display: 'Boska', Georgia, 'Times New Roman', serif;
  --font-body: 'Source Serif 4', Georgia, serif;
  --font-ui: 'General Sans', 'Helvetica Neue', system-ui, sans-serif;

  --hero-overlay: linear-gradient(
    90deg,
    oklch(from var(--color-bg) l c h / 0.99) 0%,
    oklch(from var(--color-bg) l c h / 0.96) 30%,
    oklch(from var(--color-bg) l c h / 0.78) 52%,
    oklch(from var(--color-bg) l c h / 0.3) 100%
  );
  --img-tone: none;
}

[data-theme='dark'] {
  --color-bg: #14171e;
  --color-surface: #191d25;
  --color-surface-2: #1e232c;
  --color-surface-offset: #21262f;
  --color-surface-dynamic: #2a303a;
  --color-divider: #2b313b;
  --color-border: #39404c;

  --color-text: #e4ddcb;
  --color-text-muted: #9a958a;
  --color-text-faint: #6b665c;
  --color-text-inverse: #14171e;

  --color-primary: #9db4d4;
  --color-primary-hover: #b9cae3;
  --color-primary-active: #c9d6ea;
  --color-primary-highlight: #2a323f;

  --color-accent: #c87b85;
  --color-accent-hover: #d99aa2;
  --color-accent-active: #e6b3b9;

  --shadow-sm: 0 1px 2px oklch(0 0 0 / 0.3);
  --shadow-md: 0 6px 20px oklch(0 0 0 / 0.4);
  --shadow-lg: 0 18px 48px oklch(0 0 0 / 0.55);

  --hero-overlay: linear-gradient(
    90deg,
    oklch(from var(--color-bg) l c h / 0.99) 0%,
    oklch(from var(--color-bg) l c h / 0.96) 30%,
    oklch(from var(--color-bg) l c h / 0.82) 52%,
    oklch(from var(--color-bg) l c h / 0.45) 100%
  );
  --img-tone: brightness(0.82) contrast(1.05);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme]) {
    --color-bg: #14171e;
    --color-surface: #191d25;
    --color-surface-2: #1e232c;
    --color-surface-offset: #21262f;
    --color-surface-dynamic: #2a303a;
    --color-divider: #2b313b;
    --color-border: #39404c;
    --color-text: #e4ddcb;
    --color-text-muted: #9a958a;
    --color-text-faint: #6b665c;
    --color-text-inverse: #14171e;
    --color-primary: #9db4d4;
    --color-primary-hover: #b9cae3;
    --color-primary-active: #c9d6ea;
    --color-primary-highlight: #2a323f;
    --color-accent: #c87b85;
    --color-accent-hover: #d99aa2;
    --color-accent-active: #e6b3b9;
    --hero-overlay: linear-gradient(
      90deg,
      oklch(from var(--color-bg) l c h / 0.99) 0%,
      oklch(from var(--color-bg) l c h / 0.96) 30%,
      oklch(from var(--color-bg) l c h / 0.82) 52%,
      oklch(from var(--color-bg) l c h / 0.45) 100%
    );
    --img-tone: brightness(0.82) contrast(1.05);
  }
}

/* ============================================================
   Layout primitives
   ============================================================ */
.wrap {
  width: 100%;
  max-width: var(--content-wide);
  margin-inline: auto;
  padding-inline: clamp(var(--space-5), 5vw, var(--space-16));
}
.wrap--default {
  max-width: var(--content-default);
}
.wrap--prose {
  max-width: var(--content-prose);
}
.wrap--narrow {
  max-width: var(--content-narrow);
}

section {
  padding-block: clamp(var(--space-16), 9vw, var(--space-32));
}
section.section--tight {
  padding-block: clamp(var(--space-12), 6vw, var(--space-20));
}

.body-text {
  font-size: var(--text-base);
  line-height: 1.72;
  color: var(--color-text);
}
.body-text p {
  max-width: 66ch;
}
.body-text p + p {
  margin-top: var(--space-5);
}

/* ============================================================
   Typography helpers
   ============================================================ */
.kicker {
  font-family: var(--font-ui);
  font-size: var(--text-xs);
  font-weight: 500;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--color-accent);
}
.kicker--muted {
  color: var(--color-text-faint);
}

.display {
  font-family: var(--font-display);
  font-weight: 500;
  line-height: 1.04;
  letter-spacing: -0.01em;
}
h1,
h2,
h3 {
  font-family: var(--font-display);
  font-weight: 500;
  letter-spacing: -0.01em;
}

.lede {
  font-size: var(--text-lg);
  line-height: 1.5;
  color: var(--color-text-muted);
  max-width: 56ch;
}

.rule {
  width: var(--space-12);
  height: 2px;
  background: var(--color-accent);
  border: 0;
  margin-block: var(--space-6);
}
.rule--center {
  margin-inline: auto;
}

/* ============================================================
   Header / Nav
   ============================================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background: oklch(from var(--color-bg) l c h / 0.82);
  backdrop-filter: blur(14px) saturate(1.2);
  -webkit-backdrop-filter: blur(14px) saturate(1.2);
  border-bottom: 1px solid transparent;
  transition:
    border-color var(--transition-interactive),
    background var(--transition-interactive);
}
.site-header.is-scrolled {
  border-bottom-color: oklch(from var(--color-border) l c h / 0.6);
}
.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-6);
  height: 72px;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
  color: var(--color-text);
}
.brand svg {
  color: var(--color-primary);
  flex-shrink: 0;
}
.brand__name {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 600;
  letter-spacing: -0.015em;
  line-height: 1;
}
.brand__name em {
  font-style: italic;
  font-weight: 400;
  color: var(--color-accent);
}

.nav__links {
  display: flex;
  align-items: center;
  gap: clamp(var(--space-4), 2vw, var(--space-8));
}
.nav__link {
  font-family: var(--font-ui);
  font-size: var(--text-sm);
  font-weight: 450;
  letter-spacing: 0.01em;
  color: var(--color-text-muted);
  text-decoration: none;
  position: relative;
  padding-block: var(--space-2);
}
.nav__link:hover {
  color: var(--color-text);
}
.nav__link.is-active {
  color: var(--color-text);
}
.nav__link.is-active::after {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  bottom: -2px;
  height: 2px;
  background: var(--color-accent);
}

.nav__actions {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}
.nav__links > .btn--accent {
  display: none;
}

.theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-full);
  color: var(--color-text-muted);
}
.theme-toggle:hover {
  color: var(--color-text);
  background: var(--color-surface-offset);
}

.nav__toggle {
  display: none;
  align-items: center;
  justify-content: center;
  width: 42px;
  height: 42px;
  color: var(--color-text);
  border-radius: var(--radius-md);
}

/* ============================================================
   Buttons
   ============================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  font-family: var(--font-ui);
  font-size: var(--text-sm);
  font-weight: 500;
  letter-spacing: 0.01em;
  padding: 0.7rem 1.4rem;
  border-radius: var(--radius-md);
  text-decoration: none;
  border: 1px solid transparent;
  min-height: 44px;
}
.btn--primary {
  background: var(--color-primary);
  color: var(--color-text-inverse);
}
[data-theme='dark'] .btn--primary {
  color: var(--color-bg);
}
.btn--primary:hover {
  background: var(--color-primary-hover);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}
.btn--accent {
  background: var(--color-accent);
  color: #f6f2e8;
}
.btn--accent:hover {
  background: var(--color-accent-hover);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}
.btn--ghost {
  background: transparent;
  color: var(--color-text);
  border-color: var(--color-border);
}
.btn--ghost:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
}
.btn--lg {
  padding: 0.85rem 1.7rem;
  font-size: var(--text-base);
}

.textlink {
  font-family: var(--font-ui);
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-accent);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 0.4em;
}
.textlink:hover {
  color: var(--color-accent-hover);
}
.textlink .arrow {
  transition: transform var(--transition-interactive);
}
.textlink:hover .arrow {
  transform: translateX(3px);
}

/* ============================================================
   Hero
   ============================================================ */
.hero {
  position: relative;
  overflow: hidden;
  border-bottom: 1px solid var(--color-divider);
}
.hero__bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}
.hero__bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center right;
  filter: var(--img-tone);
}
.hero__bg::after {
  content: '';
  position: absolute;
  inset: 0;
  background: var(--hero-overlay);
}
.hero__inner {
  position: relative;
  z-index: 1;
  padding-block: clamp(var(--space-24), 16vw, calc(var(--space-32) + var(--space-16)));
  max-width: 38rem;
}
.hero__title {
  font-size: var(--text-hero);
  line-height: 1.02;
  margin-top: var(--space-5);
}
.hero__title em {
  font-style: italic;
  color: var(--color-accent);
}
.hero__lede {
  margin-top: var(--space-6);
  font-size: var(--text-lg);
  line-height: 1.55;
  color: var(--color-text-muted);
  max-width: 34rem;
}
.hero__actions {
  margin-top: var(--space-8);
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
}

/* ============================================================
   Cards & grids
   ============================================================ */
.cluster {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
}

.grid {
  display: grid;
  gap: clamp(var(--space-6), 3vw, var(--space-10));
}
.grid--2 {
  grid-template-columns: repeat(2, 1fr);
}
.grid--3 {
  grid-template-columns: repeat(3, 1fr);
}

.card {
  background: var(--color-surface);
  border: 1px solid oklch(from var(--color-border) l c h / 0.7);
  border-radius: var(--radius-lg);
  padding: clamp(var(--space-6), 3vw, var(--space-8));
  transition:
    border-color var(--transition-interactive),
    box-shadow var(--transition-interactive),
    transform var(--transition-interactive);
}
.card--link {
  text-decoration: none;
  color: inherit;
  display: block;
}
.card--link:hover {
  border-color: oklch(from var(--color-primary) l c h / 0.5);
  box-shadow: var(--shadow-md);
  transform: translateY(-3px);
}
.card__index {
  font-family: var(--font-ui);
  font-size: var(--text-xs);
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--color-text-faint);
}
.card__title {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 500;
  margin-top: var(--space-3);
  line-height: 1.18;
  color: var(--color-text);
}
.card__desc {
  margin-top: var(--space-3);
  font-size: var(--text-base);
  line-height: 1.6;
  color: var(--color-text-muted);
}

/* ============================================================
   Method / numbered principles
   ============================================================ */
.principle {
  display: grid;
  grid-template-columns: 5.5rem 1fr;
  gap: clamp(var(--space-5), 3vw, var(--space-10));
  padding-block: clamp(var(--space-8), 4vw, var(--space-12));
  border-top: 1px solid var(--color-divider);
  align-items: start;
}
.principle__num {
  font-family: var(--font-display);
  font-size: var(--text-2xl);
  font-weight: 400;
  font-style: italic;
  color: var(--color-accent);
  line-height: 1;
}
.principle__title {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 500;
  line-height: 1.15;
  color: var(--color-text);
}
.principle__body {
  margin-top: var(--space-4);
  font-size: var(--text-base);
  line-height: 1.7;
  color: var(--color-text-muted);
}
.principle__body p + p {
  margin-top: var(--space-4);
}

/* ============================================================
   Essay list
   ============================================================ */
.essay {
  display: grid;
  grid-template-columns: 4.5rem 1fr auto;
  gap: clamp(var(--space-4), 3vw, var(--space-8));
  align-items: baseline;
  padding-block: clamp(var(--space-6), 3vw, var(--space-8));
  border-top: 1px solid var(--color-divider);
  text-decoration: none;
  color: inherit;
}
.essay:hover .essay__title {
  color: var(--color-accent);
}
.essay:hover .essay__cta .arrow {
  transform: translateX(3px);
}
.essay__num {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-style: italic;
  color: var(--color-text-faint);
  line-height: 1;
}
.essay__meta {
  font-family: var(--font-ui);
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-text-faint);
}
.essay__title {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 500;
  line-height: 1.22;
  margin-top: var(--space-2);
  color: var(--color-text);
  transition: color var(--transition-interactive);
}
.essay__desc {
  margin-top: var(--space-3);
  font-size: var(--text-base);
  line-height: 1.6;
  color: var(--color-text-muted);
  max-width: 60ch;
}
.essay__cta {
  font-family: var(--font-ui);
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-accent);
  white-space: nowrap;
  display: inline-flex;
  align-items: center;
  gap: 0.4em;
  align-self: center;
}
.essay__cta .arrow {
  transition: transform var(--transition-interactive);
}

/* ============================================================
   Series banner / feature block
   ============================================================ */
.feature {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  align-items: stretch;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  overflow: hidden;
  background: var(--color-surface);
}
.feature__body {
  padding: clamp(var(--space-8), 5vw, var(--space-16));
  display: flex;
  flex-direction: column;
  justify-content: center;
}
.feature__media {
  position: relative;
  min-height: 320px;
  background: var(--color-primary);
}
.feature__media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center 30%;
  filter: var(--img-tone);
}

/* ============================================================
   Themes grid
   ============================================================ */
.theme-card {
  padding: clamp(var(--space-6), 3vw, var(--space-8));
  border-radius: var(--radius-lg);
  background: var(--color-surface);
  border: 1px solid oklch(from var(--color-border) l c h / 0.7);
  height: 100%;
}
.theme-card__icon {
  color: var(--color-accent);
  margin-bottom: var(--space-4);
}
.theme-card h3 {
  font-size: var(--text-lg);
  font-weight: 500;
}
.theme-card p {
  margin-top: var(--space-3);
  font-size: var(--text-base);
  line-height: 1.6;
  color: var(--color-text-muted);
}

/* ============================================================
   Pull quote
   ============================================================ */
.pullquote {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 400;
  font-style: italic;
  line-height: 1.32;
  color: var(--color-text);
  max-width: 30ch;
  border-left: 0;
  padding-left: 0;
}
.pullquote cite {
  display: block;
  margin-top: var(--space-4);
  font-family: var(--font-ui);
  font-style: normal;
  font-size: var(--text-sm);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-text-faint);
}

/* ============================================================
   Subscribe band
   ============================================================ */
.subscribe-band {
  background: var(--color-primary);
  color: var(--color-text-inverse);
}
[data-theme='dark'] .subscribe-band {
  background: var(--color-surface-2);
  border-block: 1px solid var(--color-border);
}
.subscribe-band .kicker {
  color: oklch(from var(--color-accent) l c h / 1);
}
[data-theme='light'] .subscribe-band .kicker {
  color: #d9a0a8;
}
.subscribe-band h2 {
  color: var(--color-text-inverse);
  font-size: var(--text-2xl);
  max-width: 18ch;
}
[data-theme='dark'] .subscribe-band h2 {
  color: var(--color-text);
}
.subscribe-band p {
  color: oklch(from var(--color-text-inverse) l c h / 0.78);
  font-size: var(--text-lg);
  line-height: 1.5;
  max-width: 46ch;
  margin-top: var(--space-4);
}
[data-theme='dark'] .subscribe-band p {
  color: var(--color-text-muted);
}

/* ============================================================
   Steps (Start Here)
   ============================================================ */
.step {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: var(--space-5);
  align-items: start;
  padding-block: var(--space-6);
}
.step__num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.6rem;
  height: 2.6rem;
  border-radius: var(--radius-full);
  border: 1.5px solid var(--color-accent);
  color: var(--color-accent);
  font-family: var(--font-ui);
  font-weight: 600;
  font-size: var(--text-base);
  flex-shrink: 0;
}
.step h3 {
  font-size: var(--text-lg);
  font-weight: 500;
}
.step p {
  margin-top: var(--space-2);
  color: var(--color-text-muted);
  line-height: 1.65;
}

/* ============================================================
   About — author block
   ============================================================ */
.author {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: clamp(var(--space-5), 3vw, var(--space-8));
  align-items: center;
  padding: clamp(var(--space-6), 3vw, var(--space-8));
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
}
.author__mark {
  width: 92px;
  height: 92px;
  border-radius: var(--radius-full);
  background: var(--color-primary);
  color: var(--color-text-inverse);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-display);
  font-size: 2rem;
  font-weight: 500;
  flex-shrink: 0;
}
.author__name {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 500;
}
.author__role {
  font-family: var(--font-ui);
  font-size: var(--text-sm);
  letter-spacing: 0.04em;
  color: var(--color-text-muted);
  margin-top: var(--space-1);
}
.author__tag {
  margin-top: var(--space-3);
  font-style: italic;
  color: var(--color-text-faint);
}

.influences {
  list-style: none;
  display: grid;
  gap: var(--space-5);
}
.influences li {
  padding-left: var(--space-5);
  border-left: 2px solid var(--color-divider);
  max-width: 64ch;
}
.influences strong {
  font-family: var(--font-display);
  font-weight: 500;
  color: var(--color-text);
}
.influences span {
  color: var(--color-text-muted);
}

/* ============================================================
   Footer
   ============================================================ */
.site-footer {
  background: var(--color-surface-2);
  border-top: 1px solid var(--color-divider);
  padding-block: clamp(var(--space-12), 6vw, var(--space-20)) var(--space-10);
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: clamp(var(--space-8), 5vw, var(--space-16));
}
.footer__about {
  max-width: 36ch;
  color: var(--color-text-muted);
  margin-top: var(--space-4);
  font-size: var(--text-sm);
  line-height: 1.6;
}
.footer__col h4 {
  font-family: var(--font-ui);
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--color-text-faint);
  margin-bottom: var(--space-4);
}
.footer__col ul {
  list-style: none;
  display: grid;
  gap: var(--space-3);
}
.footer__col a {
  font-family: var(--font-ui);
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  text-decoration: none;
}
.footer__col a:hover {
  color: var(--color-text);
}
.footer__bottom {
  margin-top: clamp(var(--space-10), 5vw, var(--space-16));
  padding-top: var(--space-6);
  border-top: 1px solid var(--color-divider);
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
  justify-content: space-between;
  align-items: center;
  font-family: var(--font-ui);
  font-size: var(--text-xs);
  color: var(--color-text-faint);
}

/* ============================================================
   Page header (interior)
   ============================================================ */
.page-head {
  border-bottom: 1px solid var(--color-divider);
  padding-block: clamp(var(--space-16), 9vw, var(--space-24)) clamp(var(--space-10), 5vw, var(--space-16));
}
.page-head h1 {
  font-size: var(--text-2xl);
  margin-top: var(--space-4);
  max-width: 18ch;
}
.page-head .lede {
  margin-top: var(--space-5);
}

/* ============================================================
   Reveal animation
   ============================================================ */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition:
    opacity 0.7s cubic-bezier(0.16, 1, 0.3, 1),
    transform 0.7s cubic-bezier(0.16, 1, 0.3, 1);
}
.reveal.is-visible {
  opacity: 1;
  transform: none;
}
@media (prefers-reduced-motion: reduce) {
  .reveal {
    opacity: 1;
    transform: none;
  }
}

/* ============================================================
   Contact
   ============================================================ */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(var(--space-8), 5vw, var(--space-16));
  align-items: start;
}
.contact-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: clamp(var(--space-6), 3vw, var(--space-8));
}
.contact-card h3 {
  font-size: var(--text-lg);
  font-weight: 500;
}
.contact-card p {
  margin-top: var(--space-3);
  color: var(--color-text-muted);
  line-height: 1.65;
}

/* ============================================================
   Responsive
   ============================================================ */
@media (max-width: 900px) {
  .feature {
    grid-template-columns: 1fr;
  }
  .feature__media {
    min-height: 240px;
    order: -1;
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
  .footer__about {
    grid-column: 1 / -1;
  }
  .contact-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 760px) {
  .nav__actions .btn--accent {
    display: none;
  }
  .nav__links {
    position: fixed;
    inset: 72px 0 auto 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    padding: var(--space-4) clamp(var(--space-5), 5vw, var(--space-16));
    box-shadow: var(--shadow-lg);
    transform: translateY(-12px);
    opacity: 0;
    pointer-events: none;
    transition:
      opacity var(--transition-interactive),
      transform var(--transition-interactive);
  }
  .nav__links.is-open {
    transform: none;
    opacity: 1;
    pointer-events: auto;
  }
  .nav__link {
    padding-block: var(--space-4);
    border-bottom: 1px solid var(--color-divider);
    font-size: var(--text-base);
  }
  .nav__link.is-active::after {
    display: none;
  }
  .nav__toggle {
    display: inline-flex;
  }
  .nav__links > .btn--accent {
    display: inline-flex;
    margin-top: var(--space-4);
    justify-content: center;
  }
  .grid--2,
  .grid--3 {
    grid-template-columns: 1fr;
  }
  .principle {
    grid-template-columns: 1fr;
    gap: var(--space-3);
  }
  .principle__num {
    font-size: var(--text-xl);
  }
  .essay {
    grid-template-columns: 1fr;
    gap: var(--space-2);
  }
  .essay__num {
    font-size: var(--text-lg);
  }
  .essay__cta {
    align-self: start;
    margin-top: var(--space-2);
  }
  .author {
    grid-template-columns: 1fr;
    text-align: left;
  }
  .footer-grid {
    grid-template-columns: 1fr;
  }
}