/* ==========================================================================
   Design tokens
   ========================================================================== */

:root {
  --font-sans: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, monospace;

  /* Light theme (default) */
  --bg: #ffffff;
  --bg-alt: #f6f7f9;
  --surface: #ffffff;
  --text: #111827;
  --text-muted: #4b5563;
  --border: #e3e6eb;
  --accent: #3364b9;
  --accent-hover: #284f94;
  --accent-soft: #eaf0fa;
  --on-accent: #ffffff;
  --success: #15803d;
  --danger: #b42318;
  --shadow: 0 1px 2px rgb(16 24 40 / 0.05), 0 8px 24px rgb(16 24 40 / 0.06);

  --radius: 12px;
  --radius-sm: 8px;
  --container: 1100px;
  --gutter: clamp(1rem, 4vw, 2rem);
  --section-space: clamp(4rem, 9vw, 7rem);
  --header-height: 4rem;
  --ease: cubic-bezier(0.2, 0.7, 0.2, 1);

  color-scheme: light;
}

/* Dark theme: follows the OS unless the visitor chose light explicitly. */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0d1117;
    --bg-alt: #11161d;
    --surface: #161b22;
    --text: #e6edf3;
    --text-muted: #9ba6b2;
    --border: #2a313c;
    --accent: #82a8f2;
    --accent-hover: #a9c3f7;
    --accent-soft: rgb(130 168 242 / 0.12);
    --on-accent: #0d1117;
    --success: #4ade80;
    --danger: #ff8a80;
    --shadow: 0 1px 2px rgb(0 0 0 / 0.3), 0 8px 24px rgb(0 0 0 / 0.25);
    color-scheme: dark;
  }
}

:root[data-theme="dark"] {
  --bg: #0d1117;
  --bg-alt: #11161d;
  --surface: #161b22;
  --text: #e6edf3;
  --text-muted: #9ba6b2;
  --border: #2a313c;
  --accent: #82a8f2;
  --accent-hover: #a9c3f7;
  --accent-soft: rgb(130 168 242 / 0.12);
  --on-accent: #0d1117;
  --success: #4ade80;
  --danger: #ff8a80;
  --shadow: 0 1px 2px rgb(0 0 0 / 0.3), 0 8px 24px rgb(0 0 0 / 0.25);
  color-scheme: dark;
}

/* ==========================================================================
   Base
   ========================================================================== */

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 1rem);
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.65;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  overflow-wrap: break-word;
}

h1,
h2,
h3,
h4 {
  margin: 0;
  line-height: 1.2;
  letter-spacing: -0.02em;
  color: var(--text);
}

p {
  margin: 0;
}

img,
svg {
  display: block;
  max-width: 100%;
}

a {
  color: var(--accent);
  text-underline-offset: 3px;
}

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

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 4px;
}

ul,
ol {
  margin: 0;
  padding: 0;
}

.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

[hidden] {
  display: none !important;
}

.sprite {
  display: none;
}

.icon {
  width: 1.15em;
  height: 1.15em;
  flex-shrink: 0;
}

.visually-hidden {
  position: absolute !important;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: absolute;
  top: 0.75rem;
  left: 0.75rem;
  z-index: 100;
  padding: 0.6rem 1rem;
  border-radius: var(--radius-sm);
  background: var(--accent);
  color: var(--on-accent);
  font-weight: 600;
  text-decoration: none;
  transform: translateY(-200%);
}

.skip-link:focus {
  transform: none;
  color: var(--on-accent);
}

/* ==========================================================================
   Buttons & links
   ========================================================================== */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  min-height: 2.75rem;
  padding: 0.65rem 1.25rem;
  border: 1px solid transparent;
  border-radius: 999px;
  font: inherit;
  font-size: 0.95rem;
  font-weight: 600;
  line-height: 1;
  text-decoration: none;
  white-space: nowrap;
  cursor: pointer;
  transition: background-color 0.2s, border-color 0.2s, color 0.2s, transform 0.2s var(--ease);
}

.btn:hover {
  transform: translateY(-1px);
}

.btn-primary {
  background: var(--accent);
  color: var(--on-accent);
}

.btn-primary:hover {
  background: var(--accent-hover);
  color: var(--on-accent);
}

.btn-primary .icon {
  transition: transform 0.2s var(--ease);
}

.btn-primary:hover .icon {
  transform: translateX(3px);
}

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

.btn-secondary:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.btn:disabled {
  opacity: 0.6;
  cursor: progress;
  transform: none;
}

.icon-btn {
  display: inline-grid;
  place-items: center;
  width: 2.75rem;
  height: 2.75rem;
  padding: 0;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--surface);
  color: var(--text);
  cursor: pointer;
  transition: border-color 0.2s, color 0.2s;
}

.icon-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.text-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 600;
  text-decoration: none;
}

.text-link:hover {
  text-decoration: underline;
}

/* ==========================================================================
   Header & navigation
   ========================================================================== */

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: color-mix(in srgb, var(--bg) 85%, transparent);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--border);
}

.nav {
  display: flex;
  align-items: center;
  gap: 1rem;
  min-height: var(--header-height);
}

.nav-brand {
  margin-right: auto;
  font-weight: 700;
  color: var(--text);
  text-decoration: none;
  letter-spacing: -0.01em;
}

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

.nav-links {
  display: flex;
  gap: 0.25rem;
  list-style: none;
}

.nav-links a {
  display: block;
  padding: 0.5rem 0.75rem;
  border-radius: var(--radius-sm);
  color: var(--text-muted);
  font-size: 0.95rem;
  font-weight: 500;
  text-decoration: none;
  transition: color 0.2s, background-color 0.2s;
}

.nav-links a:hover {
  color: var(--text);
  background: var(--bg-alt);
}

.nav-toggle {
  display: none;
}

.theme-toggle .icon-sun {
  display: none;
}

[data-active-theme="dark"] .theme-toggle .icon-sun {
  display: block;
}

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

/* Collapsible menu on small screens (only when JS is available to toggle it). */
@media (max-width: 760px) {
  .js .nav-toggle {
    display: inline-grid;
    order: 2;
  }

  .js .theme-toggle {
    order: 1;
  }

  .js .nav-links {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    display: none;
    flex-direction: column;
    padding: 0.5rem var(--gutter) 1rem;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow);
  }

  .js .nav-links.is-open {
    display: flex;
  }

  .js .nav-links a {
    padding: 0.75rem;
    font-size: 1rem;
  }

  /* Without JS, let the links wrap underneath the brand. */
  html:not(.js) .nav {
    flex-wrap: wrap;
    padding-block: 0.5rem;
  }
}

/* ==========================================================================
   Hero
   ========================================================================== */

.hero {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2.5rem;
  align-items: center;
  padding-block: clamp(2.5rem, 7vw, 5.5rem) clamp(0.5rem, 2vw, 1.5rem);
}

.hero-photo {
  order: -1;
  width: min(240px, 60vw);
}

.hero-photo img {
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 5;
  object-fit: cover;
  border-radius: 20px;
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  background: var(--bg-alt);
}

.eyebrow {
  margin-bottom: 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--accent);
  letter-spacing: 0.02em;
}

.hero h1 {
  font-size: clamp(2.5rem, 7vw, 4.25rem);
  font-weight: 700;
  letter-spacing: -0.035em;
}

.hero-lead {
  max-width: 36rem;
  margin-top: 1.25rem;
  font-size: clamp(1.075rem, 2vw, 1.25rem);
  color: var(--text-muted);
}

.hero-meta {
  margin-top: 1rem;
  font-size: 0.95rem;
  font-weight: 500;
}

.availability {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  margin-top: 1.25rem;
  padding: 0.4rem 0.9rem;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--bg-alt);
  font-size: 0.875rem;
  color: var(--text-muted);
}

.status-dot {
  width: 0.5rem;
  height: 0.5rem;
  border-radius: 50%;
  background: var(--success);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--success) 25%, transparent);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 2rem;
}

.social-links {
  display: flex;
  gap: 0.5rem;
  margin-top: 1.5rem;
  list-style: none;
}

@media (min-width: 900px) {
  .hero {
    grid-template-columns: 1fr auto;
    gap: 4rem;
  }

  .hero-photo {
    order: 0;
    width: 360px;
  }
}

/* ==========================================================================
   Sections
   ========================================================================== */

.section {
  padding-block: var(--section-space);
}

.section-alt {
  background: var(--bg-alt);
  border-block: 1px solid var(--border);
}

.section-heading {
  display: flex;
  align-items: baseline;
  gap: 0.85rem;
  margin-bottom: 2.5rem;
}

.section-kicker {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--accent);
}

.section-heading h2 {
  font-size: clamp(1.75rem, 4vw, 2.25rem);
  font-weight: 700;
}

.section-intro {
  max-width: 40rem;
  margin: -1.25rem 0 2.5rem;
  color: var(--text-muted);
}

/* About */

.about {
  display: grid;
  gap: 2.5rem;
}

.about .section-heading {
  margin-bottom: 0;
}

.about-body {
  display: grid;
  gap: 1.1rem;
  max-width: 42rem;
  font-size: 1.05rem;
}

.facts {
  display: grid;
  gap: 1.25rem;
  margin: 0;
  padding: 1.5rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  align-self: start;
}

.facts dt {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.facts dd {
  margin: 0.15rem 0 0;
  font-weight: 500;
}

@media (min-width: 900px) {
  .about {
    grid-template-columns: 1fr 18rem;
    column-gap: 4rem;
  }

  .about .section-heading {
    grid-column: 1 / -1;
  }
}

/* Skills */

.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(min(100%, 300px), 1fr));
  gap: 1rem;
}

.skill-group {
  padding: 1.5rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
}

.skill-group h3 {
  margin-bottom: 1rem;
  font-size: 1rem;
  font-weight: 600;
}

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  list-style: none;
}

.tags li {
  padding: 0.3rem 0.75rem;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--text);
  font-size: 0.875rem;
  font-weight: 500;
  line-height: 1.4;
}

.tags-sm li {
  padding: 0.2rem 0.6rem;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  font-family: var(--font-mono);
  font-size: 0.75rem;
}

/* Projects */

.projects {
  display: grid;
  gap: 1.5rem;
}

@media (min-width: 900px) {
  .projects {
    grid-template-columns: repeat(2, 1fr);
  }
}

.project-card {
  display: flex;
  flex-direction: column;
  gap: 1.1rem;
  padding: clamp(1.5rem, 3vw, 2rem);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  transition: border-color 0.25s, box-shadow 0.25s, transform 0.25s var(--ease);
}

.project-card:hover {
  border-color: color-mix(in srgb, var(--accent) 45%, var(--border));
  box-shadow: var(--shadow);
  transform: translateY(-2px);
}

.project-meta {
  margin-bottom: 0.4rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-muted);
}

.project-header h3 {
  font-size: 1.4rem;
  font-weight: 700;
}

.project-summary {
  color: var(--text-muted);
}

.project-subhead {
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-muted);
}

.project-points {
  display: grid;
  gap: 0.55rem;
  padding-left: 1.1rem;
  font-size: 0.95rem;
}

.project-points li::marker {
  color: var(--accent);
}

.project-links {
  margin-top: auto;
  padding-top: 1rem;
  border-top: 1px solid var(--border);
}

.project-note {
  font-size: 0.875rem;
  color: var(--text-muted);
}

/* Experience timeline */

.timeline {
  list-style: none;
  border-left: 2px solid var(--border);
  margin-left: 0.35rem;
}

.timeline-item {
  position: relative;
  padding: 0 0 2rem 1.75rem;
}

.timeline-item:last-child {
  padding-bottom: 0;
}

.timeline-item::before {
  content: "";
  position: absolute;
  left: -0.45rem;
  top: 0.4rem;
  width: 0.8rem;
  height: 0.8rem;
  border-radius: 50%;
  background: var(--bg-alt);
  border: 2px solid var(--accent);
}

.timeline-head {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.25rem 1rem;
  margin-bottom: 0.5rem;
}

.timeline-head h3 {
  font-size: 1.05rem;
  font-weight: 600;
}

.company {
  display: inline-block;
  margin-left: 0.35rem;
  font-weight: 500;
  color: var(--accent);
}

.company::before {
  content: "· ";
  color: var(--text-muted);
}

.timeline-date {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-muted);
  white-space: nowrap;
}

.timeline-item ul {
  display: grid;
  gap: 0.3rem;
  padding-left: 1.1rem;
  max-width: 48rem;
  color: var(--text-muted);
  font-size: 0.95rem;
}

/* Education & certifications */

.credentials {
  display: grid;
  gap: 1.5rem;
}

@media (min-width: 760px) {
  .credentials {
    grid-template-columns: repeat(2, 1fr);
  }
}

.credential-group h3 {
  margin-bottom: 1rem;
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-muted);
}

.credential-list {
  display: grid;
  gap: 0.75rem;
  list-style: none;
}

.credential-list li {
  display: grid;
  gap: 0.15rem;
  padding: 1rem 1.25rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--surface);
}

.credential-name {
  font-weight: 600;
}

.credential-detail {
  font-size: 0.875rem;
  color: var(--text-muted);
}

/* Contact */

.contact {
  display: grid;
  gap: 3rem;
}

@media (min-width: 900px) {
  .contact {
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
  }
}

.contact-intro > p {
  max-width: 32rem;
  color: var(--text-muted);
}

.contact-list {
  display: grid;
  gap: 0.85rem;
  margin-top: 2rem;
  list-style: none;
}

.contact-list li {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.contact-list .icon {
  color: var(--text-muted);
}

.contact-list a {
  font-weight: 500;
}

.contact-form {
  display: grid;
  gap: 1.25rem;
  padding: clamp(1.5rem, 3vw, 2rem);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  align-self: start;
}

.field {
  display: grid;
  gap: 0.4rem;
}

.field label {
  font-size: 0.9rem;
  font-weight: 600;
}

.field input,
.field textarea {
  width: 100%;
  padding: 0.7rem 0.85rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--bg);
  color: var(--text);
  font: inherit;
  transition: border-color 0.2s, box-shadow 0.2s;
}

.field textarea {
  min-height: 8rem;
  resize: vertical;
}

.field input:focus,
.field textarea:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

.field [aria-invalid="true"] {
  border-color: var(--danger);
}

.field-error {
  font-size: 0.85rem;
  color: var(--danger);
}

.field-error:empty {
  display: none;
}

.contact-form .btn {
  justify-self: start;
}

.form-status {
  font-size: 0.95rem;
  font-weight: 500;
}

.form-status:empty {
  display: none;
}

.form-status.is-success {
  color: var(--success);
}

.form-status.is-error {
  color: var(--danger);
}

/* Footer */

.site-footer {
  padding-block: 2rem;
  font-size: 0.9rem;
  color: var(--text-muted);
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 1rem;
}

/* ==========================================================================
   Reduced motion
   ========================================================================== */

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

  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
  }

  .btn:hover,
  .project-card:hover,
  .btn-primary:hover .icon {
    transform: none;
  }
}