/* ==========================================================================
   FORMULARY NOTES — Developer-Tool Edition
   Deep navy + warm cream + clinical teal · Monospace identity
   ========================================================================== */

:root {
  /* Type scale */
  --text-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.875rem);
  --text-sm: clamp(0.875rem, 0.8rem + 0.35vw, 1rem);
  --text-base: clamp(1rem, 0.95rem + 0.25vw, 1.125rem);
  --text-lg: clamp(1.125rem, 1rem + 0.75vw, 1.5rem);
  --text-xl: clamp(1.5rem, 1.2rem + 1.25vw, 2.25rem);
  --text-2xl: clamp(2rem, 1.2rem + 2.5vw, 3.5rem);
  --text-3xl: clamp(2.5rem, 1rem + 4vw, 5rem);
  --text-hero: clamp(2.75rem, 1rem + 6vw, 6rem);

  /* 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;

  /* Fonts — Developer tool aesthetic */
  --font-display: 'Source Serif 4', Georgia, serif;
  --font-body: 'Inter', system-ui, -apple-system, sans-serif;
  --font-mono: 'JetBrains Mono', 'SF Mono', 'Menlo', monospace;

  /* Radius — slightly tighter for tech feel */
  --radius-sm: 0.25rem;
  --radius-md: 0.375rem;
  --radius-lg: 0.5rem;
  --radius-xl: 0.75rem;
  --radius-full: 9999px;

  --transition-interactive: 180ms cubic-bezier(0.16, 1, 0.3, 1);

  --content-narrow: 640px;
  --content-default: 960px;
  --content-wide: 1280px;
  --content-full: 100%;
}

/* ==========================================================================
   DARK MODE FIRST — developer-tool aesthetic
   ========================================================================== */

/* Default = dark (matches the bracket logo background) */
:root,
[data-theme='dark'] {
  --color-bg: #0e1520;
  --color-surface: #131c2a;
  --color-surface-2: #182336;
  --color-surface-offset: #1d2940;
  --color-surface-offset-2: #233048;
  --color-surface-dynamic: #2c3a55;
  --color-divider: #243149;
  --color-border: #2d3a52;

  --color-text: #e8e1cf;
  --color-text-muted: #8b95a8;
  --color-text-faint: #5a6478;
  --color-text-inverse: #0e1520;

  --color-primary: #4dbab6;
  --color-primary-hover: #6fcec9;
  --color-primary-active: #88dfdb;
  --color-primary-highlight: #1d3a3a;

  --color-accent: #e89260;
  --color-accent-2: #c976a4;

  --color-success: #6daa45;
  --color-warning: #bb653b;
  --color-error: #d163a7;

  --shadow-sm: 0 1px 2px oklch(0 0 0 / 0.3);
  --shadow-md: 0 4px 16px oklch(0 0 0 / 0.4);
  --shadow-lg: 0 16px 40px oklch(0 0 0 / 0.55);

  --grid-color: rgba(232, 225, 207, 0.04);
}

[data-theme='light'] {
  --color-bg: #f5f1e8;
  --color-surface: #faf6ed;
  --color-surface-2: #fdf9f0;
  --color-surface-offset: #ede7d6;
  --color-surface-offset-2: #e5dec9;
  --color-surface-dynamic: #d9d1ba;
  --color-divider: #d6cdb5;
  --color-border: #c7bda1;

  --color-text: #0e1520;
  --color-text-muted: #5a6478;
  --color-text-faint: #9aa1ad;
  --color-text-inverse: #f5f1e8;

  --color-primary: #0d6b6b;
  --color-primary-hover: #094f4f;
  --color-primary-active: #073838;
  --color-primary-highlight: #cfdfdf;

  --color-accent: #c45a1f;
  --color-accent-2: #8e3d6a;

  --color-success: #437a22;
  --color-warning: #964219;
  --color-error: #a12c7b;

  --shadow-sm: 0 1px 2px oklch(0.2 0.02 240 / 0.08);
  --shadow-md: 0 4px 16px oklch(0.2 0.02 240 / 0.10);
  --shadow-lg: 0 16px 40px oklch(0.2 0.02 240 / 0.18);

  --grid-color: rgba(14, 21, 32, 0.05);
}

/* Subtle grid pattern over body — defines the dev-tool aesthetic */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  pointer-events: none;
  background-image:
    radial-gradient(var(--grid-color) 1px, transparent 1px);
  background-size: 28px 28px;
  z-index: 0;
  opacity: 0.7;
}

main, .header, .footer {
  position: relative;
  z-index: 1;
}

/* ==========================================================================
   LAYOUT
   ========================================================================== */

.container {
  width: 100%;
  max-width: var(--content-wide);
  margin-inline: auto;
  padding-inline: clamp(var(--space-4), 4vw, var(--space-10));
}

.container--narrow { max-width: var(--content-default); }
.container--prose { max-width: 68ch; }

section {
  padding-block: clamp(var(--space-12), 8vw, var(--space-24));
}

/* ==========================================================================
   HEADER
   ========================================================================== */

.header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: color-mix(in oklab, var(--color-bg) 90%, transparent);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--color-border);
}

.header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-6);
  padding-block: var(--space-4);
}

.brand {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
  color: var(--color-text);
}

.brand__mark {
  width: 40px;
  height: 40px;
  color: var(--color-text);
}

.brand__mark .brand__slash {
  color: var(--color-primary);
}

.brand__name {
  font-family: var(--font-mono);
  font-size: var(--text-base);
  font-weight: 500;
  letter-spacing: -0.01em;
  line-height: 1;
}

.brand__sub {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 400;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-text-muted);
  margin-top: 4px;
}

.nav {
  display: flex;
  gap: var(--space-6);
  align-items: center;
}

.nav__link {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text-muted);
  text-decoration: none;
  letter-spacing: 0;
}

.nav__link:hover { color: var(--color-text); }
.nav__link.is-active { color: var(--color-primary); }

.theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  color: var(--color-text-muted);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  background: var(--color-surface);
}

.theme-toggle:hover {
  color: var(--color-text);
  background: var(--color-surface-offset);
}

@media (max-width: 720px) {
  .nav { gap: var(--space-4); }
  .nav__link--hide-mobile { display: none; }
  .brand__sub { display: none; }
}

/* ==========================================================================
   HERO
   ========================================================================== */

.hero {
  padding-block: clamp(var(--space-16), 10vw, var(--space-32));
  position: relative;
  overflow: hidden;
}

.hero__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(var(--space-8), 6vw, var(--space-16));
  align-items: center;
}

@media (min-width: 880px) {
  .hero__grid {
    grid-template-columns: 1.4fr 1fr;
  }
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 500;
  letter-spacing: 0.04em;
  color: var(--color-primary);
  margin-bottom: var(--space-5);
}

.eyebrow::before {
  content: '//';
  color: var(--color-primary);
  font-weight: 600;
}

.hero__title {
  font-family: var(--font-display);
  font-size: var(--text-2xl);
  font-weight: 500;
  line-height: 1.05;
  letter-spacing: -0.025em;
  color: var(--color-text);
  margin-bottom: var(--space-6);
}

@media (min-width: 880px) {
  .hero__title { font-size: var(--text-3xl); }
}

.hero__title em {
  font-style: italic;
  color: var(--color-primary);
}

.hero__lede {
  font-size: var(--text-lg);
  line-height: 1.5;
  color: var(--color-text-muted);
  max-width: 52ch;
  margin-bottom: var(--space-8);
}

.hero__cta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
}

.hero__visual {
  position: relative;
  aspect-ratio: 4 / 5;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-lg);
}

.hero__visual img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

/* ==========================================================================
   BUTTONS
   ========================================================================== */

.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-5);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-weight: 500;
  letter-spacing: -0.005em;
  border-radius: var(--radius-md);
  text-decoration: none;
  border: 1px solid transparent;
  white-space: nowrap;
}

.btn--primary {
  background: var(--color-primary);
  color: var(--color-text-inverse);
}
.btn--primary:hover { background: var(--color-primary-hover); }

.btn--ghost {
  background: transparent;
  color: var(--color-text);
  border-color: var(--color-border);
}
.btn--ghost:hover {
  background: var(--color-surface-offset);
  border-color: var(--color-text-muted);
}

.btn--lg { padding: var(--space-4) var(--space-6); font-size: var(--text-base); }

/* ==========================================================================
   PILLARS — terminal-card style
   ========================================================================== */

.pillars {
  background: var(--color-surface);
  border-block: 1px solid var(--color-border);
}

.pillars__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: var(--color-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

@media (min-width: 720px) {
  .pillars__grid { grid-template-columns: repeat(3, 1fr); }
}

.pillar {
  background: var(--color-surface-2);
  padding: var(--space-8);
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  text-decoration: none;
  color: var(--color-text);
  transition: background var(--transition-interactive);
}

.pillar:hover { background: var(--color-surface-offset); }

.pillar__num {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-primary);
  letter-spacing: 0;
}

.pillar__title {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 600;
  letter-spacing: -0.01em;
}

.pillar__desc {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  line-height: 1.55;
}

.pillar__arrow {
  margin-top: var(--space-4);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  color: var(--color-primary);
  font-weight: 500;
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
}

/* ==========================================================================
   FEATURE / ARTICLE GRID
   ========================================================================== */

.section-header {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: var(--space-6);
  margin-bottom: var(--space-10);
  border-bottom: 1px solid var(--color-border);
  padding-bottom: var(--space-5);
}

.section-header__title {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 500;
  letter-spacing: -0.015em;
}

.section-header__link {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  color: var(--color-primary);
  text-decoration: none;
  font-weight: 500;
}
.section-header__link:hover { color: var(--color-primary-hover); }

.feature-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-10);
}

@media (min-width: 880px) {
  .feature-grid {
    grid-template-columns: 1.5fr 1fr;
    gap: var(--space-12);
  }
}

.feature-card {
  display: flex;
  flex-direction: column;
  text-decoration: none;
  color: inherit;
  gap: var(--space-5);
}

.feature-card__media {
  aspect-ratio: 16 / 10;
  border-radius: var(--radius-md);
  overflow: hidden;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
}

.feature-card__media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 600ms cubic-bezier(0.16, 1, 0.3, 1);
}

.feature-card:hover .feature-card__media img { transform: scale(1.03); }

.feature-card__meta {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  letter-spacing: 0;
  font-weight: 500;
}

.feature-card__category {
  color: var(--color-primary);
}
.feature-card__category--rust { color: var(--color-accent); }
.feature-card__category--mulberry { color: var(--color-accent-2); }

.feature-card__title {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 500;
  line-height: 1.15;
  letter-spacing: -0.015em;
}

.feature-card__title--lg { font-size: var(--text-2xl); }

.feature-card__excerpt {
  font-size: var(--text-base);
  color: var(--color-text-muted);
  line-height: 1.55;
}

.side-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-6);
}

.side-card {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  text-decoration: none;
  color: inherit;
  padding-bottom: var(--space-6);
  border-bottom: 1px solid var(--color-divider);
}

.side-card:last-child { border-bottom: none; padding-bottom: 0; }

.side-card__title {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 500;
  line-height: 1.2;
  letter-spacing: -0.01em;
}

.side-card:hover .side-card__title { color: var(--color-primary); }

/* ==========================================================================
   ARTICLE INDEX GRID
   ========================================================================== */

.index-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-10);
}

@media (min-width: 640px) { .index-grid { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 960px) { .index-grid { grid-template-columns: repeat(3, 1fr); } }

/* ==========================================================================
   NEWSLETTER
   ========================================================================== */

.newsletter {
  background: var(--color-surface);
  color: var(--color-text);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: clamp(var(--space-8), 5vw, var(--space-16));
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-8);
  align-items: center;
}

@media (min-width: 880px) {
  .newsletter { grid-template-columns: 1fr 1fr; }
}

.newsletter__title {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 500;
  letter-spacing: -0.015em;
  color: var(--color-text);
  margin-bottom: var(--space-3);
}

.newsletter__desc {
  font-size: var(--text-base);
  color: var(--color-text-muted);
  line-height: 1.5;
  max-width: 42ch;
}

.newsletter__form {
  display: flex;
  gap: var(--space-2);
  flex-wrap: wrap;
}

.newsletter__input {
  flex: 1;
  min-width: 220px;
  padding: var(--space-4) var(--space-5);
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  color: var(--color-text);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
}

.newsletter__input::placeholder { color: var(--color-text-faint); }

.newsletter__input:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px color-mix(in oklab, var(--color-primary) 25%, transparent);
}

.newsletter__btn {
  background: var(--color-primary);
  color: var(--color-text-inverse);
  padding: var(--space-4) var(--space-6);
  border-radius: var(--radius-md);
  font-family: var(--font-mono);
  font-weight: 500;
  font-size: var(--text-sm);
  border: none;
}

.newsletter__btn:hover { background: var(--color-primary-hover); }

/* ==========================================================================
   PRIORAUTHRX PROMO
   ========================================================================== */

.tool-promo {
  background: var(--color-surface-offset);
  border-radius: var(--radius-lg);
  padding: clamp(var(--space-6), 4vw, var(--space-10));
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-6);
  align-items: center;
  border: 1px solid var(--color-border);
}

@media (min-width: 720px) {
  .tool-promo { grid-template-columns: auto 1fr auto; }
}

.tool-promo__icon {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-md);
  background: var(--color-primary);
  color: var(--color-text-inverse);
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.tool-promo__label {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0;
  color: var(--color-text-muted);
  margin-bottom: var(--space-1);
}

.tool-promo__title {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 500;
  letter-spacing: -0.01em;
  margin-bottom: var(--space-1);
}

.tool-promo__desc {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  line-height: 1.5;
}

/* ==========================================================================
   ARTICLE
   ========================================================================== */

.article {
  padding-block: clamp(var(--space-10), 6vw, var(--space-20));
}

.article__header {
  max-width: 68ch;
  margin: 0 auto var(--space-12);
}

.article__meta {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  letter-spacing: 0;
  font-weight: 500;
  margin-bottom: var(--space-5);
}

.article__title {
  font-family: var(--font-display);
  font-size: var(--text-2xl);
  font-weight: 500;
  letter-spacing: -0.025em;
  line-height: 1.1;
  margin-bottom: var(--space-5);
}

.article__lede {
  font-size: var(--text-lg);
  color: var(--color-text-muted);
  line-height: 1.5;
}

.article__hero {
  max-width: var(--content-wide);
  margin: 0 auto var(--space-12);
  border-radius: var(--radius-lg);
  overflow: hidden;
  aspect-ratio: 21 / 9;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
}

.article__hero img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.prose {
  max-width: 68ch;
  margin: 0 auto;
  font-size: var(--text-base);
  line-height: 1.7;
  color: var(--color-text);
}

.prose > * + * { margin-top: var(--space-5); }

.prose h2 {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 500;
  letter-spacing: -0.015em;
  margin-top: var(--space-12);
  margin-bottom: var(--space-4);
}

.prose h3 {
  font-family: var(--font-body);
  font-size: var(--text-lg);
  font-weight: 600;
  margin-top: var(--space-8);
  margin-bottom: var(--space-3);
}

.prose p { color: var(--color-text); }
.prose strong { color: var(--color-text); font-weight: 600; }

.prose a {
  color: var(--color-primary);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

.prose a:hover { color: var(--color-primary-hover); }

.prose ul, .prose ol {
  padding-left: var(--space-6);
}

.prose li { margin-top: var(--space-2); }
.prose li::marker { color: var(--color-primary); }

.prose code {
  font-family: var(--font-mono);
  font-size: 0.92em;
  background: var(--color-surface-offset);
  padding: 0.125em 0.375em;
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-border);
}

.prose blockquote {
  border-left: 3px solid var(--color-primary);
  padding-left: var(--space-5);
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-style: italic;
  color: var(--color-text);
  margin-block: var(--space-8);
}

.prose hr {
  border: none;
  border-top: 1px solid var(--color-border);
  margin-block: var(--space-10);
}

.callout {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-left: 3px solid var(--color-primary);
  border-radius: var(--radius-md);
  padding: var(--space-5) var(--space-6);
  margin-block: var(--space-8);
}

.callout__label {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-primary);
  margin-bottom: var(--space-2);
  font-weight: 600;
}

/* ==========================================================================
   FOOTER
   ========================================================================== */

.footer {
  background: var(--color-surface);
  border-top: 1px solid var(--color-border);
  padding-block: var(--space-12);
  margin-top: var(--space-20);
}

.footer__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-10);
  margin-bottom: var(--space-10);
}

@media (min-width: 720px) {
  .footer__grid { grid-template-columns: 2fr 1fr 1fr; }
}

.footer__brand-desc {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  max-width: 40ch;
  margin-top: var(--space-3);
  line-height: 1.5;
}

.footer__heading {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0;
  color: var(--color-text-muted);
  margin-bottom: var(--space-4);
  font-weight: 500;
}

.footer__list {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.footer__link {
  font-size: var(--text-sm);
  color: var(--color-text);
  text-decoration: none;
}
.footer__link:hover { color: var(--color-primary); }

.footer__legal {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: var(--space-4);
  padding-top: var(--space-6);
  border-top: 1px solid var(--color-border);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-text-muted);
}

.footer__disclaimer {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  max-width: 70ch;
  margin-top: var(--space-4);
  line-height: 1.5;
}

/* ==========================================================================
   UTILITY
   ========================================================================== */

.divider {
  height: 1px;
  background: var(--color-border);
  border: none;
  margin: 0;
}

.reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 700ms cubic-bezier(0.16, 1, 0.3, 1), transform 700ms cubic-bezier(0.16, 1, 0.3, 1);
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}