:root {
  /* Anthropic Color Palette */
  --ivory-light: #faf9f0;
  --ivory-medium: #f0eee6;
  --oat: #e8e6dc;
  --cloud-light: #d1cfc5;
  --slate-light: #a1a0a0;
  --slate-medium: #87867f;
  --slate-dark: #3d3d3a;
  --charcoal: #141413;
  --terracotta: #d97757;
  --cactus: #84b59f;
  --heather: #9d94b8;

  /* Semantic tokens — light mode */
  --bg-page:        var(--ivory-medium);
  --bg-surface:     var(--oat);
  --bg-nav:         var(--ivory-medium);
  --bg-contact:     var(--charcoal);
  --text-primary:   var(--charcoal);
  --text-secondary: var(--slate-dark);
  --text-muted:     var(--slate-medium);
  --text-contact:   var(--ivory-light);
  --text-contact-p: var(--cloud-light);
  --border-subtle:  var(--cloud-light);
  --tag-bg:         var(--cloud-light);
  --tag-text:       var(--charcoal);
  --toggle-bg:      var(--oat);
  --toggle-border:  var(--cloud-light);
  --toggle-icon:    var(--slate-dark);

  /* Typography */
  --font-main: "Inter", -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: "Fira Code", monospace;
  --font-secondary: "Tiempos Text", Georgia, "Times New Roman", serif;

  /* Spacing */
  --container-max: 1440px;
  --container-padding: clamp(2rem, 5vw, 5rem);
  --section-spacing: clamp(4rem, 10vw, 8rem);
}

/* ─── Dark theme ──────────────────────────────────────────────────────────── */
[data-theme="dark"] {
  /* Claude.ai dark UI palette — warm charcoal, not cold */
  --bg-page:        #1c1b18;
  --bg-surface:     #252420;
  --bg-nav:         #1c1b18;
  --bg-contact:     #0f0f0d;
  --text-primary:   #f0ece3;
  --text-secondary: #b5b0a7;
  --text-muted:     #6e6b64;
  --text-contact:   #f0ece3;
  --text-contact-p: #9b9690;
  --border-subtle:  #38352e;
  --tag-bg:         #333028;
  --tag-text:       #d4cfc5;
  --toggle-bg:      #2d2b27;
  --toggle-border:  #3f3c35;
  --toggle-icon:    #b5b0a7;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: var(--font-main);
  background-color: var(--bg-page);
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background-color 0.35s ease, color 0.35s ease;
}

/* ─── Navigation ────────────────────────────────────────────────────────────── */
nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background-color: var(--bg-nav);
  z-index: 1000;
  padding: 1.25rem var(--container-padding);
  transition: background-color 0.35s ease;
}

/* subtle separator that appears in dark mode */
[data-theme="dark"] nav {
  border-bottom: 1px solid var(--border-subtle);
}

.nav-container {
  max-width: var(--container-max);
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--text-primary);
  text-decoration: none;
  letter-spacing: -0.02em;
  transition: color 0.35s ease;
}

.nav-links {
  display: flex;
  gap: 2rem;
  list-style: none;
  align-items: center;
}

.nav-links a {
  color: var(--text-primary);
  text-decoration: none;
  font-size: 0.9375rem;
  font-weight: 500;
  transition: color 0.2s ease;
  position: relative;
}

.nav-links a:hover {
  color: var(--terracotta);
}

.nav-links a::after {
  content: "";
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--terracotta);
  transition: width 0.3s ease;
}

.nav-links a:hover::after {
  width: 100%;
}

/* ─── Theme toggle button ───────────────────────────────────────────────────── */
.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 10px;
  border: 1px solid var(--toggle-border);
  background-color: var(--toggle-bg);
  color: var(--toggle-icon);
  cursor: pointer;
  transition:
    background-color 0.2s ease,
    border-color 0.2s ease,
    color 0.2s ease,
    transform 0.15s ease;
  flex-shrink: 0;
}

.theme-toggle:hover {
  border-color: var(--terracotta);
  color: var(--terracotta);
  transform: scale(1.08);
}

.theme-toggle svg {
  width: 16px;
  height: 16px;
  transition: opacity 0.2s ease, transform 0.3s ease;
}

/* show/hide sun vs moon */
.icon-sun  { display: none; }
.icon-moon { display: block; }

[data-theme="dark"] .icon-sun  { display: block; }
[data-theme="dark"] .icon-moon { display: none; }

/* ─── Container ─────────────────────────────────────────────────────────────── */
.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--container-padding);
}

/* ─── Hero ──────────────────────────────────────────────────────────────────── */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding-top: 5rem;
  height: 100vh;
  scroll-snap-align: start;
  box-sizing: border-box;
  overflow-y: auto;
}

.hero-content {
  max-width: 800px;
  text-align: left;
}

.hero h1 {
  font-size: clamp(2.5rem, 8vw, 5rem);
  font-weight: 600;
  line-height: 1.1;
  margin-bottom: 1.5rem;
  letter-spacing: -0.03em;
}

.hero h1 a {
  color: var(--terracotta);
  text-decoration: underline;
  text-underline-offset: 0.15em;
  text-decoration-thickness: 0.06em;
  transition: color 0.2s ease;
}

.hero h1 a:hover {
  color: var(--text-secondary);
}

.hero p {
  font-size: clamp(1.125rem, 2.5vw, 1.5rem);
  color: var(--text-secondary);
  line-height: 1.5;
  max-width: 40ch;
  text-align: left;
  font-family: var(--font-secondary);
}

/* ─── About card ────────────────────────────────────────────────────────────── */
.about-card-banner {
  background-color: var(--bg-surface);
  border-radius: 24px;
  padding: clamp(3rem, 5vw, 4rem);
  max-width: 1440px;
  margin: 0 auto;
  border: none;
  transition: background-color 0.35s ease;
}

.about-banner-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr;
  gap: 3rem;
}

.about-banner-left {
  padding-right: 2rem;
}

.about-content p {
  font-size: clamp(1.1rem, 2.5vw, 1.2rem);
  color: var(--text-secondary);
  line-height: 1.6;
  max-width: 70ch;
  margin-bottom: 1.5rem;
  font-family: var(--font-secondary);
}

.about-content p:last-child {
  margin-bottom: 0;
}

.about-banner-right {
  border-left: none;
  padding-left: 3rem;
  display: flex;
  flex-direction: column;
}

.about-links-title {
  font-size: 0.875rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  margin-bottom: 1.5rem;
  font-weight: 600;
}

.about-links-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.about-links-list .about-link-item:first-child {
  border-bottom: 1px solid var(--border-subtle);
}

.about-link-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem;
  border-radius: 12px;
  text-decoration: none;
  color: var(--text-primary);
  transition: background-color 0.2s ease, transform 0.2s ease;
  border: none;
}

.about-link-item:not(.is-static):hover {
  background-color: var(--bg-page);
  transform: none;
}

.about-link-text h4 {
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: 0.25rem;
}

.about-link-text p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  font-family: var(--font-secondary);
}

.about-link-icon {
  color: var(--text-muted);
  transition: transform 0.2s ease, color 0.2s ease;
}

.about-link-item:not(.is-static):hover .about-link-icon {
  transform: translateX(4px);
  color: var(--terracotta);
}

.about-link-icon svg {
  width: 24px;
  height: 24px;
  stroke: currentColor;
  fill: none;
}
.about-link-icon svg.g_svg {
  fill: currentColor;
  stroke: none;
}

.about-link-item.is-static {
  padding: 1rem;
  background-color: transparent;
  border: none;
}

.skills-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

@media (max-width: 900px) {
  .about-banner-grid {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }
  .about-banner-left {
    padding-right: 0;
  }
  .about-banner-right {
    border-left: none;
    padding-left: 0;
    border-top: none;
    padding-top: 2.5rem;
  }
}

@media (max-width: 600px) {
  .about-card-banner {
    padding: 2rem;
  }
  .about-link-item {
    padding: 1rem 0.5rem;
  }
  .about-link-item.is-static {
    padding: 1rem;
  }
}

/* ─── Sections ──────────────────────────────────────────────────────────────── */
section {
  padding: var(--section-spacing) 0;
  height: 100vh;
  scroll-snap-align: start;
  overflow-y: auto;
  box-sizing: border-box;
}

.section-title {
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 600;
  margin-bottom: 3rem;
  letter-spacing: -0.02em;
}

.section-subtitle {
  font-size: 0.875rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  margin-bottom: 1rem;
  font-weight: 500;
}

/* ─── Grid & Cards ──────────────────────────────────────────────────────────── */
.grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 2rem;
}

.card {
  background-color: var(--bg-surface);
  border-radius: 24px;
  padding: 2rem;
  transition: background-color 0.35s ease;
}

.card h3 {
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: 0.75rem;
  letter-spacing: -0.01em;
}

.card p {
  color: var(--text-secondary);
  line-height: 1.6;
  font-family: var(--font-secondary);
}

.card-tag {
  display: inline-block;
  background-color: var(--tag-bg);
  color: var(--tag-text);
  padding: 0.25rem 0.75rem;
  border-radius: 12px;
  font-size: 0.75rem;
  font-weight: 500;
  margin-top: 1rem;
  margin-right: 0.5rem;
  transition: background-color 0.35s ease, color 0.35s ease;
}

/* ─── Buttons ───────────────────────────────────────────────────────────────── */
.btn {
  display: inline-block;
  background-color: var(--terracotta);
  color: white;
  padding: 0.875rem 1.75rem;
  border-radius: 12px;
  text-decoration: none;
  font-weight: 500;
  font-size: 1rem;
  border: none;
  cursor: pointer;
  transition: background-color 0.2s ease;
}

.btn:hover {
  background-color: #c26847;
}

.btn-secondary {
  background-color: transparent;
  color: var(--text-primary);
  border: 1px solid var(--text-muted);
  transition: background-color 0.2s ease, border-color 0.2s ease, color 0.2s ease;
}

.btn-secondary:hover {
  background-color: var(--bg-surface);
  border-color: var(--text-primary);
}

/* ─── Contact ───────────────────────────────────────────────────────────────── */
.contact-section {
  text-align: center;
  padding: var(--section-spacing) 0;
}

.contact-box {
  background-color: var(--bg-contact);
  color: var(--text-contact);
  border-radius: 24px;
  padding: clamp(3rem, 8vw, 4rem);
  max-width: 1440px;
  margin: 0 auto;
  transition: background-color 0.35s ease;
}

[data-theme="dark"] .contact-box {
  border: 1px solid var(--border-subtle);
}

.contact-box h2 {
  margin-bottom: 1.5rem;
}

.contact-box p {
  font-size: 1.25rem;
  max-width: 40ch;
  margin: 0 auto 2rem;
  color: var(--text-contact-p);
  font-family: var(--font-secondary);
}

.btn-group {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
}

.contact-box .btn-secondary {
  color: var(--text-contact);
  border-color: var(--text-muted);
}

.contact-box .btn-secondary:hover {
  background-color: var(--text-contact);
  color: var(--bg-contact);
  border-color: var(--text-contact);
}

/* ─── Collapsible grid ──────────────────────────────────────────────────────── */
.grid-item-hidden {
  display: none;
}

.collapsible-grid.expanded .grid-item-hidden {
  display: block;
}

/* ─── Scroll snap ───────────────────────────────────────────────────────────── */
html {
  scroll-behavior: smooth;
  scroll-snap-type: y mandatory;
}

/* ─── Accent helpers ────────────────────────────────────────────────────────── */
.accent-terracotta { color: var(--terracotta); }
.accent-cactus     { color: var(--cactus); }
.accent-heather    { color: var(--heather); }

/* ─── Spacing helpers ───────────────────────────────────────────────────────── */
.mb-1 { margin-bottom: 1rem; }
.mb-2 { margin-bottom: 2rem; }
.mb-3 { margin-bottom: 3rem; }
.mt-2 { margin-top: 2rem; }

/* ─── Responsive ────────────────────────────────────────────────────────────── */
@media (max-width: 768px) {
  .nav-links {
    gap: 1rem;
  }

  .nav-links a {
    font-size: 0.875rem;
  }

  .hero {
    min-height: 80vh;
    height: 100vh;
  }

  .grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 600px) {
  .nav-container {
    flex-direction: column;
    gap: 1rem;
  }

  .nav-links {
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.75rem 1rem;
  }

  .section-title {
    margin-bottom: 2rem;
  }

  .card {
    padding: 1.5rem;
  }
}

@media (max-width: 768px) {
  html {
    scroll-snap-type: none;
  }

  .hero,
  section {
    height: auto;
    min-height: 0;
    scroll-snap-align: none;
    overflow-y: visible;
  }

  .hero {
    padding-top: 8rem;
    padding-bottom: 4rem;
  }
}