/* Design tokens */
:root {
  --color-bg: #ffffff;
  --color-surface: #f5f6f8;
  --color-text: #1a1a1a;
  --color-muted: #555b65;
  --color-border: #e2e4e8;
  --color-accent: #2557d6;

  --font-sans: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;

  --space-1: 0.5rem;
  --space-2: 1rem;
  --space-3: 1.5rem;
  --space-4: 2rem;
  --space-6: 4rem;

  --radius: 0.5rem;
  --max-width: 68rem;
  --header-height: 4rem;

  color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
  :root {
    --color-bg: #0f1115;
    --color-surface: #171a21;
    --color-text: #e8e9ec;
    --color-muted: #a3a8b3;
    --color-border: #2a2f3a;
    --color-accent: #8ab0ff;
  }
}

/* Base */
*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
}

body {
  margin: 0;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.6;
}

a {
  color: var(--color-accent);
  text-underline-offset: 0.15em;
}

a:hover {
  text-decoration-thickness: 2px;
}

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

/* Layout */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin-inline: auto;
  padding-inline: var(--space-2);
}

@media (min-width: 48rem) {
  .container {
    padding-inline: var(--space-4);
  }
}

/* Keep anchored sections clear of the sticky header */
section[id] {
  scroll-margin-top: calc(var(--header-height) + var(--space-2));
}

/* Skip link: hidden until focused */
.skip-link {
  position: absolute;
  top: -100%;
  left: var(--space-2);
  z-index: 100;
  padding: var(--space-1) var(--space-2);
  background: var(--color-text);
  color: var(--color-bg);
  border-radius: var(--radius);
}

.skip-link:focus {
  top: var(--space-2);
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
}

.header-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-1) var(--space-3);
  min-height: var(--header-height);
}

.site-name {
  color: var(--color-text);
  font-weight: 700;
  text-decoration: none;
}

.nav-list {
  display: flex;
  gap: var(--space-3);
  margin: 0;
  padding: 0;
  list-style: none;
}

.nav-list a {
  display: inline-block;
  padding-block: var(--space-1);
  color: var(--color-muted);
  text-decoration: none;
}

.nav-list a:hover {
  color: var(--color-text);
}

/* Hero */
.hero {
  padding-block: var(--space-6) var(--space-4);
}

.eyebrow {
  margin: 0 0 var(--space-1);
  color: var(--color-muted);
  font-weight: 600;
}

h1 {
  margin: 0;
  font-size: clamp(2rem, 5vw + 1rem, 3.5rem);
  line-height: 1.1;
  letter-spacing: -0.02em;
}

.lede {
  max-width: 40rem;
  margin: var(--space-3) 0 0;
  color: var(--color-muted);
  font-size: 1.125rem;
}

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

h2 {
  margin: 0 0 var(--space-3);
  font-size: 1.5rem;
}

/* Projects */
.project-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(16rem, 1fr));
  gap: var(--space-3);
  margin: 0;
  padding: 0;
  list-style: none;
}

.card {
  padding: var(--space-3);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
}

.card h3 {
  margin: 0 0 var(--space-1);
  font-size: 1.125rem;
}

.card p {
  margin: 0;
  color: var(--color-muted);
}

/* Contact */
.contact-list {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1) var(--space-3);
  margin: var(--space-2) 0 0;
  padding: 0;
  list-style: none;
}

/* Footer */
.site-footer {
  margin-top: var(--space-6);
  padding-block: var(--space-3);
  border-top: 1px solid var(--color-border);
  color: var(--color-muted);
  font-size: 0.875rem;
}

.site-footer p {
  margin: 0;
}