/* Dennis GEO — global styles
   Aesthetic: technical documentation meets research paper.
   Typography: Instrument Serif (display) · Geist (body) · Geist Mono (accents) */

:root {
  --bg: #FFFFFF;
  --bg-soft: #F7F8FB;
  --ink: #0F1629;
  --ink-2: #2C3347;
  --muted: #6B7280;
  --muted-2: #9CA3AF;
  --line: #E5E7EB;
  --line-strong: #0F1629;
  --accent: #1C3D7F;
  --accent-soft: #EEF2FA;
  --serif: "Instrument Serif", Georgia, "Times New Roman", serif;
  --sans: "Geist", -apple-system, BlinkMacSystemFont, "Helvetica Neue", Arial, sans-serif;
  --mono: "Geist Mono", ui-monospace, SFMono-Regular, Menlo, monospace;
  --max: 1200px;
  --pad: clamp(1rem, 3vw, 2rem);
}

* { box-sizing: border-box; }
html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img, svg { max-width: 100%; display: block; }
hr {
  border: 0;
  border-top: 1px solid var(--line);
  margin: 3rem 0;
}

/* — Typography — */
.display {
  font-family: var(--serif);
  font-weight: 400;
  font-size: clamp(2.6rem, 6.5vw, 5rem);
  line-height: 1.02;
  letter-spacing: -0.02em;
  margin: 0 0 1.5rem;
}
.display em { font-style: italic; }
.display .accent { color: var(--accent); font-style: italic; }

h1, h2, h3, h4 {
  font-family: var(--serif);
  font-weight: 400;
  letter-spacing: -0.015em;
  line-height: 1.15;
}

h2 {
  font-size: clamp(1.75rem, 3vw, 2.4rem);
  margin: 0 0 1.25rem;
}
h3 {
  font-size: clamp(1.25rem, 2vw, 1.45rem);
  margin: 0 0 .5rem;
}
h4 {
  font-size: 1.05rem;
  margin: 0 0 .5rem;
}

p {
  margin: 0 0 1rem;
  max-width: 62ch;
}

a {
  color: var(--ink);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
  transition: color .15s ease;
}
a:hover { color: var(--accent); }

.lede {
  font-size: clamp(1.1rem, 1.4vw, 1.25rem);
  color: var(--ink-2);
  max-width: 58ch;
  line-height: 1.55;
}

.muted { color: var(--muted); }
.mono {
  font-family: var(--mono);
  font-size: .85em;
  letter-spacing: 0;
}
.small { font-size: .9rem; }
.tiny { font-size: .78rem; color: var(--muted); }

.kicker {
  display: inline-flex;
  align-items: center;
  gap: .6rem;
  font-family: var(--mono);
  font-size: .78rem;
  letter-spacing: 0.02em;
  color: var(--muted);
  margin: 0 0 1.75rem;
}
.kicker::before {
  content: "";
  display: inline-block;
  width: 20px;
  height: 1px;
  background: var(--accent);
}

.section-num {
  font-family: var(--mono);
  font-size: .72rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 0 0 .75rem;
}

/* — Layout — */
.wrap {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 var(--pad);
}
.wrap-tight {
  max-width: 780px;
  margin: 0 auto;
  padding: 0 var(--pad);
}

.section {
  padding: 5rem 0;
  border-bottom: 1px solid var(--line);
}
.section:last-of-type { border-bottom: 0; }
.section-soft {
  background: var(--bg-soft);
  border-bottom: 1px solid var(--line);
}
.section-soft .plan-single,
.section-soft .feature-grid-light > article {
  background: var(--bg);
}
.section-dark {
  background: var(--ink);
  color: #F5F5F5;
  border-bottom: 0;
}
.section-dark h2,
.section-dark h3,
.section-dark a { color: #FFFFFF; }
.section-dark p { color: #B5B5B5; }
.section-dark .muted { color: #8A8A8A; }
.section-dark .section-num { color: #C7B8FF; }

/* — Header / Nav — */
.site-header {
  position: sticky;
  top: 0;
  background: rgba(255,255,255,0.92);
  backdrop-filter: saturate(180%) blur(10px);
  -webkit-backdrop-filter: saturate(180%) blur(10px);
  border-bottom: 1px solid var(--line);
  z-index: 50;
}
.site-header-inner {
  position: relative;
  max-width: var(--max);
  margin: 0 auto;
  padding: 1.25rem var(--pad);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: .75rem;
  text-decoration: none;
  color: var(--ink);
  font-family: var(--serif);
  font-size: 1.25rem;
  letter-spacing: -0.01em;
}
.brand-text {
  display: inline-flex;
  flex-direction: column;
  line-height: 1.05;
}
.brand-tagline {
  font-family: var(--sans);
  font-size: .7rem;
  font-weight: 400;
  color: var(--muted);
  letter-spacing: 0.02em;
  margin-top: 2px;
}
.brand img {
  width: 45px;
  height: 45px;
}
.site-footer .brand {
  font-size: 1.75rem;
  gap: 1rem;
  align-items: center;
}
.site-footer .brand img {
  width: 80px;
  height: 80px;
}
.site-footer .brand-tagline {
  display: inline;
  font-size: .85rem;
  margin-top: 4px;
}
.brand .name-geo {
  font-style: italic;
  color: var(--accent);
  margin-left: .15rem;
}
.site-nav {
  display: flex;
  gap: 1.5rem;
  align-items: center;
}
.site-nav a {
  font-size: .92rem;
  text-decoration: none;
  color: var(--ink-2);
  font-weight: 500;
}
.site-nav a.is-cta {
  color: #fff;
  background: var(--accent);
  padding: .5rem .9rem;
  border-radius: 2px;
}
.site-nav a.is-cta:hover { background: #16316B; color: #fff; }

.nav-toggle {
  display: none;
  background: transparent;
  border: 0;
  padding: 8px;
  cursor: pointer;
  color: var(--ink);
}
.nav-toggle svg { width: 24px; height: 24px; display: block; }
.nav-toggle .icon-close { display: none; }
.nav-toggle[aria-expanded="true"] .icon-open { display: none; }
.nav-toggle[aria-expanded="true"] .icon-close { display: block; }

@media (max-width: 760px) {
  .site-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--bg);
    border-bottom: 1px solid var(--line);
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: .5rem 0;
    display: none;
  }
  .site-nav.is-open { display: flex; }
  .site-nav a {
    padding: .85rem var(--pad);
    border-top: 1px solid var(--line);
    font-size: 1rem;
  }
  .site-nav a:first-child { border-top: 0; }
  .site-nav a.is-cta {
    margin: .5rem var(--pad) .25rem;
    padding: .75rem 1rem;
    text-align: center;
    border-top: 0;
    border-radius: 2px;
  }
  .nav-toggle { display: inline-flex; }
}

/* — Hero — */
.hero {
  padding: clamp(4rem, 8vw, 7rem) 0 clamp(3rem, 5vw, 5rem);
  border-bottom: 1px solid var(--line);
}
.hero .kicker { margin-bottom: 2.5rem; }
.hero .display { max-width: 18ch; }
.hero .lede { margin: 1.5rem 0 2rem; }

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: .75rem;
  margin-top: 2rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: .5rem;
  padding: .85rem 1.4rem;
  font-family: var(--sans);
  font-weight: 500;
  font-size: .95rem;
  text-decoration: none;
  border-radius: 2px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: background .15s ease, color .15s ease, border-color .15s ease, transform .15s ease;
}
.btn-primary {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}
.btn-primary:hover { background: #16316B; border-color: #16316B; color: #fff; }
.btn-ghost {
  background: transparent;
  color: var(--ink);
  border-color: var(--line-strong);
}
.btn-ghost:hover { background: var(--ink); color: var(--bg); }
.btn-block { width: 100%; }

/* — Stat bar — */
.stat-bar {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  background: var(--line);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.stat-bar > div {
  background: var(--bg);
  padding: 1.75rem 1.5rem;
}
.stat-bar .n {
  font-family: var(--serif);
  font-size: clamp(1.75rem, 3vw, 2.5rem);
  line-height: 1;
  letter-spacing: -0.02em;
  display: block;
  margin-bottom: .5rem;
}
.stat-bar .l {
  font-family: var(--mono);
  font-size: .75rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--muted);
}
@media (max-width: 720px) {
  .stat-bar { grid-template-columns: 1fr 1fr; }
}

/* — Feature grid (light, homepage) — */
.feature-grid-light {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
  margin-top: 2.5rem;
}
.feature-grid-light > article {
  background: var(--bg);
  padding: 1.75rem;
  border: 1px solid var(--line);
  border-radius: 4px;
  transition: border-color .15s ease, transform .15s ease;
}
.feature-grid-light > article:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
}
.feature-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border-radius: 8px;
  background: var(--accent-soft);
  color: var(--accent);
  margin-bottom: 1.1rem;
}
.feature-icon svg { width: 22px; height: 22px; }
.feature-grid-light h3 {
  font-size: 1.2rem;
  margin-bottom: .6rem;
  color: var(--ink);
}
.feature-grid-light p {
  margin: 0;
  color: var(--ink-2);
  font-size: .96rem;
  line-height: 1.55;
}
@media (max-width: 900px) { .feature-grid-light { grid-template-columns: 1fr 1fr; } }
@media (max-width: 600px) { .feature-grid-light { grid-template-columns: 1fr; } }

/* — Feature grid (dense, dark — used on /features) — */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background: var(--line);
  margin-top: 3rem;
  border: 1px solid var(--line);
}
.feature-grid > article {
  background: var(--bg);
  padding: 2rem 1.75rem;
}
.feature-grid h3 {
  font-size: 1.15rem;
}
.feature-grid p {
  margin: 0;
  color: var(--muted);
  font-size: .95rem;
}
.feature-grid .feature-num {
  font-family: var(--mono);
  font-size: .72rem;
  color: var(--muted-2);
  letter-spacing: 0.1em;
  margin-bottom: 1rem;
  display: block;
}
@media (max-width: 900px) { .feature-grid { grid-template-columns: 1fr 1fr; } }
@media (max-width: 600px) { .feature-grid { grid-template-columns: 1fr; } }

/* — Step list (numbered) — */
.steps {
  list-style: none;
  padding: 0;
  margin: 3rem 0 0;
  counter-reset: step;
}
.steps > li {
  display: grid;
  grid-template-columns: 4rem 1fr;
  gap: 2rem;
  padding: 2rem 0;
  border-top: 1px solid var(--line);
}
.steps > li:last-child { border-bottom: 1px solid var(--line); }
.steps > li::before {
  counter-increment: step;
  content: "0" counter(step);
  font-family: var(--mono);
  font-size: .85rem;
  color: var(--accent);
  letter-spacing: 0.05em;
  padding-top: .3rem;
}
.steps h3 { font-size: 1.35rem; margin-bottom: .5rem; }
.steps p { margin: 0; color: var(--ink-2); }
@media (max-width: 600px) {
  .steps > li { grid-template-columns: 1fr; gap: .5rem; }
}

/* — Pricing — single plan presentation — */
.plan-single {
  max-width: 520px;
  margin: 0 auto;
  padding: 3rem 2.5rem;
  border: 1px solid var(--line);
  border-radius: 4px;
  text-align: center;
  background: var(--bg);
}
.plan-single .plan-label {
  font-family: var(--mono);
  font-size: .78rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 0 0 1rem;
}
.plan-single .plan-title {
  font-family: var(--serif);
  font-size: 2rem;
  line-height: 1.1;
  letter-spacing: -0.015em;
  color: var(--ink);
  margin: 0 0 2rem;
}
.plan-single .plan-price {
  font-family: var(--serif);
  font-size: 4rem;
  font-weight: 400;
  line-height: 1;
  letter-spacing: -0.02em;
  margin: 0 0 2rem;
  color: var(--accent);
}
.plan-single .plan-price .suffix {
  font-family: var(--sans);
  font-size: 1rem;
  color: var(--muted);
  margin-left: .5rem;
  letter-spacing: 0;
}
.plan-single .plan-list {
  list-style: none;
  padding: 0;
  margin: 0 0 2.5rem;
  text-align: left;
}
.plan-single .plan-list li {
  padding: .65rem 0;
  border-top: 1px solid var(--line);
  font-size: .96rem;
  color: var(--ink-2);
}
.plan-single .plan-list li:first-child { border-top: 0; }
.plan-single-cta {
  display: flex;
  flex-direction: column;
  gap: .6rem;
}
.plan-single-cta .btn { width: 100%; }
@media (min-width: 520px) {
  .plan-single-cta { flex-direction: row; justify-content: center; }
  .plan-single-cta .btn { width: auto; }
}

/* — Pricing (legacy two-plan — deprecated) — */
.plans {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  margin-top: 3rem;
  border: 1px solid var(--line);
}
.plan {
  padding: 2.5rem 2rem;
  display: flex;
  flex-direction: column;
  border-right: 1px solid var(--line);
}
.plan:last-child { border-right: 0; }
.plan-label {
  font-family: var(--mono);
  font-size: .75rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 0 0 1rem;
}
.plan-paid .plan-label { color: var(--accent); }
.plan-price {
  font-family: var(--serif);
  font-size: 3.5rem;
  font-weight: 400;
  line-height: 1;
  letter-spacing: -0.02em;
  margin: 0 0 .25rem;
}
.plan-price .suffix { font-size: 1rem; color: var(--muted); margin-left: .5rem; font-family: var(--sans); }
.plan h3 {
  font-family: var(--serif);
  font-size: 1.5rem;
  margin: 1rem 0 .5rem;
}
.plan-list {
  list-style: none;
  padding: 0;
  margin: 1.5rem 0 2rem;
  flex: 1;
}
.plan-list li {
  padding: .55rem 0;
  border-top: 1px solid var(--line);
  font-size: .95rem;
  color: var(--ink-2);
}
.plan-list li:first-child { border-top: 0; }
.plan-note {
  font-family: var(--mono);
  font-size: .75rem;
  color: var(--muted);
  text-align: center;
  margin: 1rem 0 0;
}
@media (max-width: 720px) {
  .plans { grid-template-columns: 1fr; }
  .plan { border-right: 0; border-bottom: 1px solid var(--line); }
  .plan:last-child { border-bottom: 0; }
}

/* — FAQ — */
.faq-list { margin-top: 2.5rem; }
.faq-list details {
  border-top: 1px solid var(--line);
  padding: 1.25rem 0;
}
.faq-list details:last-of-type { border-bottom: 1px solid var(--line); }
.faq-list summary {
  font-family: var(--serif);
  font-size: 1.25rem;
  cursor: pointer;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  line-height: 1.3;
  letter-spacing: -0.01em;
}
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary::after {
  content: "+";
  font-family: var(--mono);
  font-size: 1.3rem;
  color: var(--accent);
  margin-left: 1rem;
  flex-shrink: 0;
}
.faq-list details[open] summary::after { content: "−"; }
.faq-list details p {
  margin: .75rem 0 0;
  color: var(--ink-2);
}

/* — Blog list — */
.post-list { list-style: none; padding: 0; margin: 3rem 0 0; }
.post-list li {
  border-top: 1px solid var(--line);
  padding: 1.75rem 0;
  display: grid;
  grid-template-columns: 160px 1fr;
  gap: 2rem;
  align-items: baseline;
}
.post-list li:last-child { border-bottom: 1px solid var(--line); }
.post-list .post-date {
  font-family: var(--mono);
  font-size: .82rem;
  color: var(--muted);
}
.post-list h3 {
  font-size: 1.35rem;
  margin: 0 0 .4rem;
}
.post-list h3 a { text-decoration: none; }
.post-list p { margin: 0; color: var(--muted); font-size: .95rem; }
@media (max-width: 640px) {
  .post-list li { grid-template-columns: 1fr; gap: .25rem; }
}

/* — Article body (blog posts) — */
.article {
  padding: clamp(3rem, 6vw, 5rem) 0;
}
.article header {
  max-width: 780px;
  margin: 0 auto 3rem;
  padding: 0 var(--pad);
  border-bottom: 1px solid var(--line);
  padding-bottom: 2.5rem;
}
.article h1 {
  font-size: clamp(2rem, 4vw, 3rem);
  line-height: 1.1;
  letter-spacing: -0.02em;
  margin: 0 0 1rem;
}
.article .post-meta {
  font-family: var(--mono);
  font-size: .82rem;
  color: var(--muted);
  margin: 0;
}
.article .prose {
  max-width: 700px;
  margin: 0 auto;
  padding: 0 var(--pad);
  font-size: 1.05rem;
  line-height: 1.75;
}
.article .prose h2 {
  font-size: 1.65rem;
  margin: 2.5rem 0 1rem;
}
.article .prose h3 {
  font-size: 1.25rem;
  margin: 2rem 0 .75rem;
}
.article .prose p { max-width: none; }
.article .prose ul, .article .prose ol { padding-left: 1.25rem; }
.article .prose li { margin: .25rem 0; }
.article .prose blockquote {
  border-left: 2px solid var(--accent);
  padding: .5rem 0 .5rem 1.25rem;
  margin: 1.5rem 0;
  font-family: var(--serif);
  font-style: italic;
  font-size: 1.2rem;
  color: var(--ink-2);
}
.article .prose code {
  font-family: var(--mono);
  font-size: .9em;
  background: var(--bg-soft);
  padding: .15rem .4rem;
  border-radius: 2px;
  border: 1px solid var(--line);
}
.article .prose pre {
  background: var(--bg-soft);
  border: 1px solid var(--line);
  padding: 1rem;
  overflow-x: auto;
  border-radius: 2px;
  font-size: .9rem;
}
.article .prose pre code { background: none; border: 0; padding: 0; }

/* — Callout — */
.callout {
  border: 1px solid var(--line);
  padding: 1.5rem;
  margin: 2rem 0;
  background: var(--bg-soft);
  border-radius: 2px;
}
.callout-label {
  font-family: var(--mono);
  font-size: .72rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--accent);
  margin: 0 0 .5rem;
}
.callout p:last-child { margin: 0; }

/* — CTA band — */
.cta-band {
  background: var(--ink);
  color: #fff;
  padding: 4rem 0;
  text-align: center;
}
.cta-band h2 {
  font-size: clamp(1.75rem, 3vw, 2.4rem);
  color: #fff;
  max-width: 22ch;
  margin-left: auto;
  margin-right: auto;
}
.cta-band p {
  color: #B5B5B5;
  max-width: 50ch;
  margin: 0 auto 2rem;
}
.cta-band .btn-primary {
  background: #fff;
  color: var(--ink);
  border-color: #fff;
}
.cta-band .btn-primary:hover { background: var(--accent); border-color: var(--accent); color: #fff; }
.cta-band .btn-ghost {
  color: #fff;
  border-color: #3A3A3A;
}
.cta-band .btn-ghost:hover { background: #fff; color: var(--ink); border-color: #fff; }

/* — Footer — */
.site-footer {
  padding: 3.5rem 0 2rem;
  background: var(--bg);
  border-top: 1px solid var(--line);
  font-size: .92rem;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1fr;
  gap: 2rem;
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 var(--pad);
}
.footer-grid h4 {
  font-family: var(--mono);
  font-size: .72rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 0 0 1rem;
  font-weight: 400;
}
.footer-grid ul { list-style: none; padding: 0; margin: 0; }
.footer-grid li { padding: .25rem 0; }
.footer-grid a { text-decoration: none; color: var(--ink-2); }
.footer-grid a:hover { color: var(--accent); }
.footer-bottom {
  max-width: var(--max);
  margin: 3rem auto 0;
  padding: 2rem var(--pad) 0;
  border-top: 1px solid var(--line);
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-family: var(--mono);
  font-size: .75rem;
  color: var(--muted);
  flex-wrap: wrap;
  gap: 1rem;
}
@media (max-width: 760px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 2.5rem 1.5rem;
  }
  .footer-grid > div:first-child {
    grid-column: 1 / -1;
  }
  .site-footer .brand { font-size: 1.5rem; }
  .site-footer .brand img { width: 64px; height: 64px; }
  .footer-bottom { flex-direction: column; align-items: flex-start; gap: .5rem; }
}

/* — Utility — */
.center { text-align: center; }
.center .display, .center h2, .center p { margin-left: auto; margin-right: auto; }
.mt-0 { margin-top: 0; }
.mb-0 { margin-bottom: 0; }

/* — Skip link — */
.skip {
  position: absolute;
  left: -9999px;
  top: 0;
}
.skip:focus {
  left: 1rem;
  top: 1rem;
  background: var(--ink);
  color: var(--bg);
  padding: .5rem 1rem;
  z-index: 100;
}