/* ─── CSS Variables ─── */
  :root {
    --surface:               #f6faff;
    --surface-dim:           #d3dbe3;
    --surface-container-lowest: #ffffff;
    --surface-container-low: #edf4fd;
    --surface-container:     #e7eff7;
    --surface-container-high:#e1e9f1;
    --surface-container-highest:#dbe3ec;
    --on-surface:            #151c22;
    --on-surface-variant:    #44474a;
    --outline:               #75777b;
    --outline-variant:       #c5c6ca;
    --primary:               #0c1014;
    --on-primary:            #ffffff;
    --primary-container:     #212529;
    --on-primary-container:  #888c91;
    --on-primary-fixed:      #181c20;
    --on-primary-fixed-variant: #43474c;
    --secondary:             #466270;
    --on-secondary:          #ffffff;
    --secondary-container:   #c6e4f4;
    --on-secondary-container:#4a6774;
    --background:            #f6faff;
    --on-background:         #151c22;
    --inverse-surface:       #293138;
    --inverse-on-surface:    #eaf2fa;
    --error:                 #ba1a1a;

    --font-display:    'Playfair Display', Georgia, serif;
    --font-body:       'Inter', system-ui, sans-serif;

    --display-lg-size:  48px;
    --display-lg-lh:    1.1;
    --display-lg-ls:    -0.02em;
    --display-lg-wt:    700;

    --display-mob-size: 36px;
    --display-mob-lh:   1.2;

    --headline-size:    32px;
    --headline-mob-size:28px;
    --headline-lh:      1.2;

    --title-lg-size:    20px;
    --title-lg-lh:      1.4;
    --title-lg-wt:      600;

    --body-lg-size:     18px;
    --body-lg-lh:       1.6;

    --body-md-size:     16px;
    --body-md-lh:       1.6;

    --label-md-size:    14px;
    --label-md-lh:      1.2;
    --label-md-ls:      0.05em;
    --label-md-wt:      500;

    --container-margin: 24px;
    --gutter:           16px;
    --section-mobile:   48px;
    --section-desktop:  96px;
    --unit:             8px;
  }

  /* ─── Reset ─── */
  *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
  html { scroll-behavior: smooth; }
  img { display: block; max-width: 100%; }
  a { text-decoration: none; color: inherit; }
  ul { list-style: none; }
  button { cursor: pointer; background: none; border: none; font: inherit; }

  /* ─── Base ─── */
  body {
    font-family: var(--font-body);
    background-color: var(--background);
    color: var(--on-background);
    min-height: 100dvh;
    -webkit-font-smoothing: antialiased;
  }

  ::selection { background: var(--secondary-container); }

  /* ─── Scroll reveal ─── */
  .reveal {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
  }
  .reveal.active {
    opacity: 1;
    transform: translateY(0);
  }

  /* ─── Header ─── */
  header {
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 50;
    background: rgba(246,250,255,0.80);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(197,198,202,0.30);
    transition: padding 0.3s ease, box-shadow 0.3s ease;
  }
  header.scrolled {
    padding-top: 8px !important;
    padding-bottom: 8px !important;
    box-shadow: 0 1px 4px rgba(0,0,0,0.06);
  }
  .header-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px var(--container-margin);
    max-width: 1440px;
    margin: 0 auto;
    transition: padding 0.3s ease;
  }
  .logo {
    font-family: var(--font-display);
    font-size: var(--headline-mob-size);
    font-weight: 600;
    letter-spacing: -0.01em;
    color: var(--primary);
    line-height: 1;
  }

  /* ─── Desktop Nav ─── */
  nav.desktop {
    display: none;
    align-items: center;
    gap: 32px;
  }
  @media (min-width: 768px) {
    nav.desktop { display: flex; }
  }
  nav.desktop a {
    font-family: var(--font-body);
    font-size: var(--label-md-size);
    font-weight: var(--label-md-wt);
    letter-spacing: var(--label-md-ls);
    text-transform: uppercase;
    color: var(--on-surface-variant);
    transition: color 0.3s;
  }
  nav.desktop a:hover { color: var(--primary); }
  nav.desktop .btn-contact {
    padding: 8px 20px;
    background: var(--primary);
    color: var(--on-primary);
    font-size: var(--label-md-size);
    font-weight: var(--label-md-wt);
    letter-spacing: var(--label-md-ls);
    text-transform: uppercase;
    transition: opacity 0.3s;
  }
  nav.desktop .btn-contact:hover { 
    opacity: 0.85;
    color: var(--on-primary);
  }

  /* ─── Mobile menu button ─── */
  .menu-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary);
    padding: 4px;
  }
  @media (min-width: 768px) { .menu-btn { display: none; } }

  /* Hamburger icon */
  .menu-icon {
    width: 24px;
    height: 18px;
    position: relative;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
  }
  .menu-icon span {
    display: block;
    height: 2px;
    background: var(--primary);
    border-radius: 2px;
    transition: all 0.3s ease;
    transform-origin: center;
  }
  .menu-btn.open .menu-icon span:nth-child(1) {
    transform: translateY(8px) rotate(45deg);
  }
  .menu-btn.open .menu-icon span:nth-child(2) {
    opacity: 0;
    transform: scaleX(0);
  }
  .menu-btn.open .menu-icon span:nth-child(3) {
    transform: translateY(-8px) rotate(-45deg);
  }

  /* ─── Mobile overlay nav ─── */
  .mobile-nav {
    position: fixed;
    top: 0; left: 0; right: 0; bottom: 0;
    background: var(--surface-container-lowest);
    z-index: 40;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 40px;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.4s ease;
  }
  .mobile-nav.open {
    opacity: 1;
    pointer-events: all;
  }
  .mobile-nav a {
    font-family: var(--font-display);
    font-size: var(--headline-size);
    font-weight: 600;
    color: var(--primary);
    transition: opacity 0.2s;
  }
  .mobile-nav a:hover { opacity: 0.6; }

  /* ─── Main ─── */
  main { padding-top: 72px; }

  /* ─── Section base ─── */
  section {
    padding: var(--section-mobile) var(--container-margin);
  }
  @media (min-width: 768px) {
    section { padding: var(--section-desktop) var(--container-margin); }
  }

  /* ─── Hero ─── */
  .hero {
    min-height: calc(100vh - 72px);
    display: flex;
    align-items: center;
    overflow: hidden;
  }
  .hero-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--gutter);
    width: 100%;
    max-width: 1440px;
    margin: 0 auto;
    align-items: center;
  }
  @media (min-width: 768px) {
    .hero-grid {
      grid-template-columns: 7fr 5fr;
    }
  }
  .hero h1 {
    font-family: var(--font-display);
    font-size: var(--display-mob-size);
    font-weight: var(--display-lg-wt);
    line-height: var(--display-mob-lh);
    color: var(--primary);
    margin-bottom: 32px;
    max-width: 600px;
  }
  @media (min-width: 768px) {
    .hero h1 {
      font-size: var(--display-lg-size);
      line-height: var(--display-lg-lh);
      letter-spacing: var(--display-lg-ls);
    }
  }
  .hero-image-wrap {
    aspect-ratio: 4/5;
    overflow: hidden;
    position: relative;
    filter: grayscale(1);
    transition: filter 0.7s ease;
  }
  .hero-image-wrap:hover { filter: grayscale(0); }
  .hero-image-wrap img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: top;
  }

  /* ─── Section: Story ─── */
  .story {
    background: var(--surface-container-lowest);
  }
  .story-inner {
    max-width: 900px;
    margin: 0 auto;
  }
  .section-eyebrow {
    display: inline-block;
    border-bottom: 1px solid var(--primary);
    margin-bottom: 24px;
  }
  .section-eyebrow span {
    font-family: var(--font-body);
    font-size: var(--label-md-size);
    font-weight: var(--label-md-wt);
    letter-spacing: var(--label-md-ls);
    text-transform: uppercase;
    color: var(--primary);
  }
  .story-quote {
    font-family: var(--font-display);
    font-size: var(--headline-mob-size);
    font-style: italic;
    font-weight: 600;
    line-height: var(--headline-lh);
    color: var(--primary);
    margin-bottom: 40px;
  }
  @media (min-width: 768px) {
    .story-quote { font-size: var(--headline-size); }
  }
  .story-cols {
    display: grid;
    grid-template-columns: 1fr;
    gap: 48px;
  }
  @media (min-width: 768px) {
    .story-cols { grid-template-columns: 1fr 1fr; }
  }
  .story-cols p {
    font-family: var(--font-body);
    font-size: var(--body-lg-size);
    line-height: var(--body-lg-lh);
    color: var(--on-surface-variant);
  }

  /* ─── Section: Education ─── */
  .education {
    border-top: 1px solid rgba(197,198,202,0.1);
    border-bottom: 1px solid rgba(197,198,202,0.1);
  }
  .education-inner { max-width: 1200px; margin: 0 auto; }
  .section-title {
    font-family: var(--font-display);
    font-size: var(--headline-size);
    font-weight: 600;
    color: var(--primary);
    margin-bottom: 64px;
  }
  .edu-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 48px;
  }
  @media (min-width: 768px) {
    .edu-grid { grid-template-columns: 1fr 1fr 1fr; }
  }
  .edu-card {
    border-left: 1px solid var(--outline-variant);
    padding: 16px 0 16px 32px;
    display: flex;
    flex-direction: column;
    gap: 16px;
  }
  .edu-year {
    font-family: var(--font-body);
    font-size: var(--label-md-size);
    font-weight: var(--label-md-wt);
    letter-spacing: var(--label-md-ls);
    color: var(--secondary);
  }
  .edu-title {
    font-family: var(--font-body);
    font-size: var(--title-lg-size);
    font-weight: var(--title-lg-wt);
    line-height: var(--title-lg-lh);
    color: var(--primary);
  }
  .edu-desc {
    font-family: var(--font-body);
    font-size: var(--body-md-size);
    line-height: var(--body-md-lh);
    color: var(--on-surface-variant);
  }

  /* ─── Section: Skills ─── */
  .skills { background: var(--surface-container-low); }
  .skills-inner { max-width: 1200px; margin: 0 auto; }
  .skills-header {
    display: flex;
    flex-direction: column;
    gap: 16px;
    margin-bottom: 64px;
  }
  @media (min-width: 768px) {
    .skills-header {
      flex-direction: row;
      justify-content: space-between;
      align-items: baseline;
    }
  }
  .skills-subtitle {
    font-size: var(--body-md-size);
    line-height: var(--body-md-lh);
    color: var(--on-surface-variant);
    max-width: 400px;
  }
  .skills-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--gutter);
  }
  @media (min-width: 768px) {
    .skills-grid { grid-template-columns: 1fr 1fr 1fr; }
  }
  .skill-card {
    background: var(--surface-container-lowest);
    padding: 40px;
    border: 1px solid rgba(197,198,202,0.20);
    transition: border-color 0.5s ease;
  }
  .skill-card:hover { border-color: var(--primary); }
  .skill-icon {
    font-size: 36px;
    color: var(--primary);
    margin-bottom: 24px;
    line-height: 1;
    user-select: none;
  }
  .skill-card h3 {
    font-family: var(--font-body);
    font-size: var(--title-lg-size);
    font-weight: var(--title-lg-wt);
    color: var(--primary);
    margin-bottom: 16px;
  }
  .skill-list { display: flex; flex-direction: column; gap: 12px; }
  .skill-list li {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: var(--body-md-size);
    line-height: var(--body-md-lh);
    color: var(--on-surface-variant);
  }
  .skill-dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: rgba(12,16,20,0.30);
    flex-shrink: 0;
  }

  /* ─── Section: Projects ─── */
  .projects-inner { max-width: 100%; }
  .projects-header {
    text-align: center;
    margin-bottom: 64px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
  }
  .projects-eyebrow {
    font-family: var(--font-body);
    font-size: var(--label-md-size);
    font-weight: var(--label-md-wt);
    letter-spacing: var(--label-md-ls);
    text-transform: uppercase;
    color: var(--secondary);
  }
  .projects-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 32px;
    max-width: 1440px;
    margin: 0 auto;
  }
  @media (min-width: 768px) {
    .projects-grid { grid-template-columns: 1fr 1fr; }
  }
  @media (min-width: 1024px) {
    .projects-grid { grid-template-columns: 1fr 1fr 1fr 1fr; }
  }
  .gallery-card {
    cursor: pointer;
  }
  /* Staggered top margin on desktop */
  @media (min-width: 1024px) {
    .gallery-card:nth-child(2),
    .gallery-card:nth-child(4) {
      margin-top: 96px;
    }
  }
  .gallery-card-img {
    aspect-ratio: 1/1;
    overflow: hidden;
    border: 1px solid rgba(197,198,202,0.10);
    margin-bottom: 24px;
    background: var(--surface-container-high);
  }
  .gallery-card-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    filter: grayscale(1);
    transition: filter 0.7s ease, transform 0.6s cubic-bezier(0.16,1,0.3,1);
  }
  .gallery-card:hover .gallery-card-img img {
    filter: grayscale(0);
    transform: scale(1.02);
  }
  .gallery-card h3 {
    font-family: var(--font-body);
    font-size: var(--title-lg-size);
    font-weight: var(--title-lg-wt);
    line-height: var(--title-lg-lh);
    color: var(--primary);
    margin-bottom: 8px;
    transition: transform 0.3s ease;
  }
  .gallery-card:hover h3 { transform: translateX(8px); }
  .gallery-card .proj-meta {
    font-size: var(--label-md-size);
    font-weight: var(--label-md-wt);
    letter-spacing: var(--label-md-ls);
    color: var(--secondary);
    margin-bottom: 8px;
  }
  .gallery-card .proj-desc {
    font-size: var(--body-md-size);
    line-height: var(--body-md-lh);
    color: var(--on-surface-variant);
    display: -webkit-box;
    -webkit-box-orient: vertical;
    overflow: hidden;
  }

  /* ─── Section: Contact ─── */
  .contact {
    background: var(--primary);
    color: var(--on-primary);
  }
  .contact-inner {
    max-width: 900px;
    margin: 0 auto;
    text-align: center;
  }
  .contact h2 {
    font-family: var(--font-display);
    font-size: var(--display-mob-size);
    font-weight: var(--display-lg-wt);
    line-height: var(--display-mob-lh);
    color: var(--on-primary);
    margin-bottom: 32px;
  }
  @media (min-width: 768px) {
    .contact h2 {
      font-size: var(--display-lg-size);
      line-height: var(--display-lg-lh);
    }
  }
  .contact-sub {
    font-size: var(--body-lg-size);
    line-height: var(--body-lg-lh);
    color: rgba(255,255,255,0.75);
    margin-bottom: 48px;
  }
  .contact-actions {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 24px;
  }
  @media (min-width: 768px) {
    .contact-actions {
      flex-direction: row;
      justify-content: center;
    }
  }
  .btn-primary-inv {
    display: inline-block;
    width: 100%;
    max-width: 280px;
    padding: 20px 40px;
    background: var(--background);
    color: var(--primary);
    font-family: var(--font-body);
    font-size: var(--title-lg-size);
    font-weight: var(--title-lg-wt);
    text-align: center;
    transition: transform 0.3s ease, opacity 0.3s ease;
  }
  @media (min-width: 768px) {
    .btn-primary-inv { width: auto; }
  }
  .btn-primary-inv:hover {
    transform: scale(1.04);
  }
  .btn-primary-inv:active {
    transform: scale(0.97);
  }
  .contact-links {
    display: flex;
    gap: 32px;
  }
  .contact-links a {
    font-size: var(--body-md-size);
    color: rgba(255,255,255,0.65);
    transition: color 0.3s;
  }
  .contact-links a:hover { color: #fff; }

  /* ─── Footer ─── */
  footer {
    background: var(--background);
    padding: 64px var(--container-margin);
    border-top: 1px solid rgba(197,198,202,0.20);
  }
  .footer-inner {
    max-width: 1440px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: var(--gutter);
  }
  @media (min-width: 768px) {
    .footer-inner {
      flex-direction: row;
      justify-content: space-between;
      align-items: center;
    }
  }
  .footer-logo {
    font-family: var(--font-display);
    font-size: var(--headline-size);
    font-weight: 600;
    color: var(--primary);
  }
  .footer-links {
    display: flex;
    flex-wrap: wrap;
    gap: 32px 16px;
  }
  .footer-links a {
    font-size: var(--body-md-size);
    color: var(--on-surface-variant);
    transition: color 0.3s;
    text-underline-offset: 4px;
  }
  .footer-links a:hover {
    color: var(--primary);
    text-decoration: underline;
  }
  .footer-copy {
    font-size: var(--body-md-size);
    color: var(--on-surface-variant);
  }

  /* ─── Utility SVG icons ─── */
  .icon-svg {
    width: 40px;
    height: 40px;
    fill: var(--primary);
    margin-bottom: 24px;
  }