/* === Design Tokens === */
:root {
  /* Colors */
  --color-ink: #1a1a2e;
  --color-ink-light: #4a4a6a;
  --color-ink-muted: #7a7a9a;
  --color-surface: #ffffff;
  --color-surface-alt: #f6f6fa;
  --color-surface-warm: #fafaf8;
  --color-accent: #2d5a9e;
  --color-accent-hover: #1e3f73;
  --color-accent-light: #e8eef7;
  --color-border: #e2e2ea;
  --color-border-light: #efefef;

  /* Spacing (4px base) */
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 32px;
  --space-2xl: 48px;
  --space-3xl: 64px;
  --space-4xl: 96px;

  /* Typography */
  --font-body: "Segoe UI", system-ui, -apple-system, sans-serif;
  --font-heading: "Segoe UI", system-ui, -apple-system, sans-serif;
  --font-mono: "Cascadia Code", "Fira Code", ui-monospace, monospace;
  --line-height-body: 1.65;
  --line-height-heading: 1.2;
  --letter-spacing-tight: -0.02em;

  /* Layout */
  --max-width: 1080px;
  --max-width-narrow: 720px;
}

/* === Dark Mode === */
@media (prefers-color-scheme: dark) {
  :root {
    --color-ink: #e8e8f0;
    --color-ink-light: #b0b0c8;
    --color-ink-muted: #8888a8;
    --color-surface: #14141e;
    --color-surface-alt: #1a1a28;
    --color-surface-warm: #18182a;
    --color-accent: #6b9edd;
    --color-accent-hover: #8db8f0;
    --color-accent-light: #1e2a3e;
    --color-border: #2a2a3e;
    --color-border-light: #222238;
  }
}

/* === Reset === */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

/* === Base === */
html {
  scroll-behavior: smooth;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}

body {
  font-family: var(--font-body);
  font-size: clamp(1rem, 0.95rem + 0.25vw, 1.125rem);
  line-height: var(--line-height-body);
  color: var(--color-ink);
  background: var(--color-surface);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* === Skip Link === */
.skip-link {
  position: absolute;
  top: -100%;
  left: var(--space-md);
  padding: var(--space-sm) var(--space-md);
  background: var(--color-accent);
  color: #fff;
  text-decoration: none;
  border-radius: 0 0 4px 4px;
  z-index: 1000;
  font-size: 0.875rem;
}

.skip-link:focus {
  top: 0;
}

/* === Typography === */
h1, h2, h3 {
  font-family: var(--font-heading);
  line-height: var(--line-height-heading);
  letter-spacing: var(--letter-spacing-tight);
  color: var(--color-ink);
}

h1 {
  font-size: clamp(2rem, 1.5rem + 2.5vw, 3.25rem);
  font-weight: 700;
}

h2 {
  font-size: clamp(1.5rem, 1.2rem + 1.5vw, 2rem);
  font-weight: 600;
}

h3 {
  font-size: clamp(1.125rem, 1rem + 0.5vw, 1.375rem);
  font-weight: 600;
}

p {
  max-width: 65ch;
}

a {
  color: var(--color-accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 2px;
  transition: color 0.15s ease;
}

a:hover {
  color: var(--color-accent-hover);
}

a:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
  border-radius: 2px;
}

/* === Layout === */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin-inline: auto;
  padding-inline: var(--space-lg);
}

.container--narrow {
  max-width: var(--max-width-narrow);
}

/* === Header === */
.site-header {
  padding: var(--space-lg) 0;
  border-bottom: 1px solid var(--color-border-light);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-lg);
}

.site-name {
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: var(--letter-spacing-tight);
  color: var(--color-ink);
  text-decoration: none;
}

.site-name:hover {
  color: var(--color-accent);
}

.site-nav {
  display: flex;
  gap: var(--space-lg);
  list-style: none;
}

.site-nav a {
  color: var(--color-ink-light);
  text-decoration: none;
  font-size: 0.9375rem;
  font-weight: 500;
}

.site-nav a:hover {
  color: var(--color-accent);
}

/* === Hero === */
.hero {
  padding: var(--space-4xl) 0;
  background: var(--color-surface-alt);
  border-bottom: 1px solid var(--color-border-light);
}

.hero h1 {
  margin-bottom: var(--space-lg);
}

.hero .tagline {
  font-size: clamp(1.125rem, 1rem + 0.5vw, 1.375rem);
  color: var(--color-ink-light);
  max-width: 55ch;
  margin-bottom: var(--space-xl);
}

/* === Sections === */
.section {
  padding: var(--space-4xl) 0;
}

.section + .section {
  border-top: 1px solid var(--color-border-light);
}

.section__header {
  margin-bottom: var(--space-2xl);
}

.section__header h2 {
  margin-bottom: var(--space-sm);
}

.section__header p {
  color: var(--color-ink-light);
  font-size: 1.0625rem;
}

/* === Services Grid === */
.services-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--space-xl);
  list-style: none;
}

.service-card {
  padding: var(--space-xl);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  background: var(--color-surface);
}

.service-card h3 {
  margin-bottom: var(--space-sm);
}

.service-card p {
  color: var(--color-ink-light);
  font-size: 0.9375rem;
}

/* === Founder === */
.founder {
  background: var(--color-surface-alt);
}

.founder-content {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-xl);
}

.founder-content p {
  color: var(--color-ink-light);
}

.founder-content p:first-of-type {
  color: var(--color-ink);
  font-size: 1.0625rem;
}

.founder-links {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-md);
  list-style: none;
  margin-top: var(--space-lg);
}

.founder-links a {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  padding: var(--space-sm) var(--space-md);
  border: 1px solid var(--color-border);
  border-radius: 6px;
  font-size: 0.875rem;
  font-weight: 500;
  text-decoration: none;
  color: var(--color-ink-light);
  transition: border-color 0.15s ease, color 0.15s ease;
}

.founder-links a:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

/* === CTA === */
.cta {
  background: var(--color-accent-light);
  text-align: center;
}

.cta h2 {
  margin-bottom: var(--space-md);
}

.cta p {
  margin-inline: auto;
  color: var(--color-ink-light);
  margin-bottom: var(--space-xl);
}

.btn {
  display: inline-block;
  padding: var(--space-sm) var(--space-xl);
  background: var(--color-accent);
  color: #fff;
  text-decoration: none;
  font-weight: 600;
  font-size: 1rem;
  border-radius: 6px;
  transition: background 0.15s ease;
}

.btn:hover {
  background: var(--color-accent-hover);
  color: #fff;
}

.btn:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
}

/* === Footer === */
.site-footer {
  padding: var(--space-2xl) 0;
  border-top: 1px solid var(--color-border-light);
  font-size: 0.875rem;
  color: var(--color-ink-muted);
}

.site-footer .container {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: var(--space-md);
}

.footer-links {
  display: flex;
  gap: var(--space-lg);
  list-style: none;
}

.footer-links a {
  color: var(--color-ink-muted);
  text-decoration: none;
}

.footer-links a:hover {
  color: var(--color-accent);
}

/* === 404 === */
.error-page {
  min-height: 80vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
}

.error-page h1 {
  font-size: clamp(4rem, 3rem + 5vw, 8rem);
  color: var(--color-border);
  line-height: 1;
  margin-bottom: var(--space-md);
}

.error-page p {
  color: var(--color-ink-muted);
  margin-inline: auto;
  margin-bottom: var(--space-lg);
}