/* ============================================
   DESIGN TOKENS
   ============================================ */
:root {
  --color-bg:        #FFFFFF;
  --color-bg-alt:    #F9FAFB;
  --color-text:      #111827;
  --color-text-sec:  #4B5563;
  --color-border:    #E5E7EB;
  --color-accent:    #2E4057;
  --color-accent-h:  #1B2A3B;

  --font-sans:  'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-serif: 'Playfair Display', Georgia, serif;

  --space-xs:  0.5rem;
  --space-sm:  1rem;
  --space-md:  1.5rem;
  --space-lg:  2.5rem;
  --space-xl:  4rem;
  --space-2xl: 6rem;
  --space-3xl: 8rem;

  --max-width: 1200px;
  --header-h:  72px;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.7;
}

img  { max-width:100%; display:block; }
a    { color:inherit; text-decoration:none; }
ul,ol{ list-style:none; }

.container {
  width:100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-md);
}

/* ============================================
   HEADER
   ============================================ */
.site-header {
  position: fixed;
  top:0; left:0; right:0;
  z-index: 100;
  height: var(--header-h);
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--color-border);
}
.header-inner {
  display:flex;
  align-items:center;
  justify-content:space-between;
  height:100%;
}
.site-logo {
  font-size: 1.125rem;
  font-weight: 600;
  letter-spacing: -0.02em;
}
.nav-links {
  display:flex;
  gap: var(--space-lg);
}
.nav-links a {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-text-sec);
  transition: color 0.2s;
}
.nav-links a:hover { color: var(--color-text); }

.nav-toggle {
  display:none;
  background:none;
  border:none;
  cursor:pointer;
  padding: var(--space-xs);
}
.nav-toggle span {
  display:block;
  width:22px;
  height:2px;
  background: var(--color-text);
  margin:5px 0;
  transition: transform 0.2s, opacity 0.2s;
}

/* ============================================
   HERO
   ============================================ */
.hero {
  padding-top: calc(var(--header-h) + var(--space-3xl));
  padding-bottom: var(--space-2xl);
}
.hero-inner {
  display:grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-xl);
  align-items:center;
}
.hero-content { max-width:560px; }

.hero-label {
  font-size: 0.8125rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-accent);
  margin-bottom: var(--space-xs);
}
.hero-title {
  font-family: var(--font-serif);
  font-size: clamp(2.25rem, 4vw, 3.25rem);
  font-weight:700;
  line-height:1.15;
  letter-spacing:-0.02em;
  margin-bottom: var(--space-md);
}
.hero-subtitle {
  font-size:1.0625rem;
  line-height:1.75;
  color: var(--color-text-sec);
  margin-bottom: var(--space-lg);
  max-width:480px;
}
.btn-primary {
  display:inline-block;
  padding: 0.875rem 2rem;
  background: var(--color-accent);
  color:#fff;
  font-family: var(--font-sans);
  font-size:0.875rem;
  font-weight:600;
  letter-spacing:0.02em;
  border:none;
  cursor:pointer;
  transition: background 0.2s;
}
.btn-primary:hover { background: var(--color-accent-h); }

.btn-outline {
  display:inline-block;
  padding: 0.875rem 2rem;
  border: 1px solid var(--color-border);
  color: var(--color-text);
  font-family: var(--font-sans);
  font-size:0.875rem;
  font-weight:600;
  letter-spacing:0.02em;
  cursor:pointer;
  transition: border-color 0.2s;
  background: transparent;
}
.btn-outline:hover { border-color: var(--color-text); }

.hero-actions { display:flex; gap: var(--space-sm); flex-wrap:wrap; }

.hero-image-wrapper {
  display:flex;
  justify-content:flex-end;
  align-items:center;
}
.hero-headshot {
  width:340px;
  height:400px;
  background: var(--color-bg-alt);
  border:1px solid var(--color-border);
  display:flex;
  align-items:center;
  justify-content:center;
  overflow:hidden;
}
.hero-headshot img {
  width:100%;
  height:100%;
  object-fit:cover;
}
.headshot-placeholder-text {
  font-size:0.8125rem;
  color: var(--color-text-sec);
  letter-spacing:0.05em;
  text-transform:uppercase;
}

/* ============================================
   STATS BAR
   ============================================ */
.stats-bar {
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  padding: var(--space-lg) 0;
  background: var(--color-bg);
}
.stats-inner {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-md);
  text-align:center;
}
.stat-number {
  font-family: var(--font-serif);
  font-size: 2rem;
  font-weight:700;
  color: var(--color-text);
  line-height:1;
  margin-bottom:0.25rem;
}
.stat-number .accent { color: var(--color-accent); }
.stat-label {
  font-size:0.8125rem;
  color: var(--color-text-sec);
  font-weight:500;
  text-transform:uppercase;
  letter-spacing:0.06em;
}

/* ============================================
   SECTIONS
   ============================================ */
.section {
  padding: var(--space-3xl) 0;
}
.section--alt {
  background: var(--color-bg-alt);
}
.section-label {
  font-size:0.8125rem;
  font-weight:600;
  text-transform:uppercase;
  letter-spacing:0.1em;
  color: var(--color-accent);
  margin-bottom: var(--space-xs);
}
.section-title {
  font-family: var(--font-serif);
  font-size: clamp(1.75rem, 3vw, 2.5rem);
  font-weight:700;
  line-height:1.2;
  letter-spacing:-0.02em;
  margin-bottom: var(--space-sm);
}
.section-desc {
  font-size:1.0625rem;
  color: var(--color-text-sec);
  line-height:1.7;
  max-width:600px;
  margin-bottom: var(--space-xl);
}

/* ============================================
   ABOUT — TWO-COLUMN + CARDS
   ============================================ */
.about-intro {
  display:grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-xl);
  margin-bottom: var(--space-xl);
}
.about-intro p {
  font-size:1rem;
  color: var(--color-text-sec);
  line-height:1.8;
  margin-bottom: var(--space-sm);
}
.about-cards {
  display:grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-md);
}
.about-card {
  border:1px solid var(--color-border);
  padding: var(--space-lg);
  background: var(--color-bg);
}
.about-card h3 {
  font-size:1rem;
  font-weight:600;
  margin-bottom: 0.5rem;
  letter-spacing:-0.01em;
}
.about-card p {
  font-size:0.9375rem;
  color: var(--color-text-sec);
  line-height:1.65;
}

/* ============================================
   EXPERIENCE TIMELINE
   ============================================ */
.timeline { max-width:720px; }

.tl-item {
  padding: var(--space-lg) 0;
  border-bottom: 1px solid var(--color-border);
}
.tl-item:first-child { padding-top:0; }
.tl-item:last-child  { border-bottom:none; }

.tl-role {
  font-size:1.0625rem;
  font-weight:600;
  margin-bottom:0.125rem;
}
.tl-org {
  font-size:0.9375rem;
  color: var(--color-text-sec);
  margin-bottom:0.125rem;
}
.tl-date {
  font-size:0.8125rem;
  color: var(--color-text-sec);
  opacity:0.7;
  margin-bottom: var(--space-sm);
}
.tl-bullets li {
  font-size:0.9375rem;
  color: var(--color-text-sec);
  line-height:1.65;
  padding-left:1rem;
  position:relative;
  margin-bottom:0.375rem;
}
.tl-bullets li::before {
  content:'';
  position:absolute;
  left:0;
  top:0.6em;
  width:4px;
  height:4px;
  background: var(--color-accent);
  border-radius:50%;
}

/* ============================================
   ACHIEVEMENTS GRID
   ============================================ */
.filter-tabs {
  display:flex;
  gap:0.5rem;
  margin-bottom: var(--space-lg);
  flex-wrap:wrap;
}
.filter-btn {
  padding: 0.5rem 1.25rem;
  font-family: var(--font-sans);
  font-size:0.8125rem;
  font-weight:600;
  cursor:pointer;
  border:1px solid var(--color-border);
  background:transparent;
  color: var(--color-text-sec);
  transition: all 0.2s;
  letter-spacing:0.02em;
}
.filter-btn:hover {
  border-color: var(--color-text);
  color: var(--color-text);
}
.filter-btn.active {
  background: var(--color-accent);
  color:#fff;
  border-color: var(--color-accent);
}

.achievements-grid {
  display:grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-md);
}
.achievement-card {
  border:1px solid var(--color-border);
  padding: var(--space-lg);
  background: var(--color-bg);
  transition: border-color 0.2s;
}
.achievement-card:hover { border-color:#D1D5DB; }
.achievement-card.hidden { display:none; }

.achievement-type {
  font-size:0.6875rem;
  font-weight:600;
  text-transform:uppercase;
  letter-spacing:0.1em;
  color: var(--color-accent);
  margin-bottom: var(--space-sm);
}
.achievement-card h3 {
  font-size:1rem;
  font-weight:600;
  margin-bottom:0.25rem;
  letter-spacing:-0.01em;
}
.achievement-meta {
  font-size:0.8125rem;
  color: var(--color-text-sec);
  margin-bottom: var(--space-sm);
}
.achievement-card p {
  font-size:0.875rem;
  color: var(--color-text-sec);
  line-height:1.65;
}

/* ============================================
   SKILLS
   ============================================ */
.skills-grid {
  display:grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-lg);
}
.skill-category h3 {
  font-size:0.8125rem;
  font-weight:600;
  text-transform:uppercase;
  letter-spacing:0.1em;
  color: var(--color-accent);
  margin-bottom: var(--space-sm);
}
.skill-pills {
  display:flex;
  flex-wrap:wrap;
  gap:0.5rem;
}
.pill {
  font-size:0.8125rem;
  font-weight:500;
  color: var(--color-text-sec);
  padding: 0.375rem 0.875rem;
  border:1px solid var(--color-border);
}

/* ============================================
   EDUCATION
   ============================================ */
.education-grid {
  display:grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-md);
}
.education-card {
  border:1px solid var(--color-border);
  padding: var(--space-lg);
  background: var(--color-bg);
}
.education-card h3 {
  font-size:1rem;
  font-weight:600;
  margin-bottom:0.25rem;
}
.education-card .ed-date {
  font-size:0.8125rem;
  color: var(--color-text-sec);
  margin-bottom: var(--space-sm);
}
.education-card p {
  font-size:0.9375rem;
  color: var(--color-text-sec);
  line-height:1.65;
}

/* ============================================
   PROJECTS
   ============================================ */
.projects-grid {
  display:grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-xl);
}
.project-card {
  border:1px solid var(--color-border);
  background: var(--color-bg);
  transition: border-color 0.2s;
}
.project-card:hover { border-color:#D1D5DB; }

.project-thumbnail {
  width:100%;
  aspect-ratio: 16/10;
  background: var(--color-bg-alt);
  border-bottom:1px solid var(--color-border);
  display:flex;
  align-items:center;
  justify-content:center;
  overflow:hidden;
}
.project-thumbnail img {
  width:100%; height:100%; object-fit:cover;
}
.thumbnail-placeholder {
  font-size:0.75rem;
  color: var(--color-text-sec);
  text-transform:uppercase;
  letter-spacing:0.08em;
}
.project-info {
  padding: var(--space-md) var(--space-md) var(--space-lg);
}
.project-status {
  display:inline-block;
  font-size:0.6875rem;
  font-weight:600;
  text-transform:uppercase;
  letter-spacing:0.08em;
  color: var(--color-accent);
  border:1px solid var(--color-accent);
  padding: 0.1875rem 0.625rem;
  margin-bottom: var(--space-sm);
}
.project-title {
  font-size:1.125rem;
  font-weight:600;
  margin-bottom:0.375rem;
  letter-spacing:-0.01em;
}
.project-desc {
  font-size:0.9375rem;
  color: var(--color-text-sec);
  line-height:1.6;
  margin-bottom: var(--space-sm);
}
.project-tags {
  display:flex;
  gap:0.5rem;
  flex-wrap:wrap;
  margin-bottom: var(--space-sm);
}
.project-tag {
  font-size:0.75rem;
  font-weight:500;
  color: var(--color-text-sec);
  border:1px solid var(--color-border);
  padding:0.25rem 0.625rem;
}
.project-link {
  font-size:0.875rem;
  font-weight:600;
  color: var(--color-accent);
  display:inline-flex;
  align-items:center;
  gap:0.375rem;
  transition: opacity 0.2s;
}
.project-link:hover { opacity:0.7; }
.project-link .arrow { transition: transform 0.2s; }
.project-link:hover .arrow { transform:translateX(3px); }

/* ============================================
   CONNECT / CONTACT
   ============================================ */
.connect-grid {
  display:grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-md);
  margin-bottom: var(--space-xl);
}
.connect-card {
  border:1px solid var(--color-border);
  padding: var(--space-lg);
  text-align:center;
  transition: border-color 0.2s;
}
.connect-card:hover { border-color:#D1D5DB; }
.connect-card strong {
  display:block;
  font-size:0.9375rem;
  margin-bottom:0.25rem;
}
.connect-card span {
  font-size:0.8125rem;
  color: var(--color-text-sec);
}

.contact-content p {
  font-size:1.0625rem;
  color: var(--color-text-sec);
  line-height:1.75;
  margin-bottom: var(--space-lg);
  max-width:600px;
}
.contact-email {
  font-size:1.25rem;
  font-weight:600;
  color: var(--color-accent);
  border-bottom:2px solid var(--color-accent);
  padding-bottom:0.125rem;
  transition: opacity 0.2s;
}
.contact-email:hover { opacity:0.7; }

/* ============================================
   FOOTER
   ============================================ */
.site-footer {
  padding: var(--space-lg) 0;
  border-top:1px solid var(--color-border);
}
.footer-inner {
  display:flex;
  align-items:center;
  justify-content:space-between;
}
.footer-copy {
  font-size:0.8125rem;
  color: var(--color-text-sec);
}
.footer-links {
  display:flex;
  gap: var(--space-md);
}
.footer-links a {
  font-size:0.8125rem;
  font-weight:500;
  color: var(--color-text-sec);
  transition: color 0.2s;
}
.footer-links a:hover { color: var(--color-text); }

/* ============================================
   RESPONSIVE — TABLET (≤ 900px)
   ============================================ */
@media (max-width:900px) {
  .hero-inner       { grid-template-columns:1fr; }
  .hero-image-wrapper{ justify-content:flex-start; }
  .hero-headshot     { width:100%; max-width:400px; height:360px; }
  .about-intro       { grid-template-columns:1fr; }
  .about-cards       { grid-template-columns:1fr; }
  .projects-grid     { grid-template-columns:1fr; }
  .skills-grid       { grid-template-columns:1fr; }
  .education-grid    { grid-template-columns:1fr; }
  .achievements-grid { grid-template-columns:1fr 1fr; }
  .connect-grid      { grid-template-columns:1fr 1fr; }
  .stats-inner       { grid-template-columns:repeat(2,1fr); }
}

/* ============================================
   RESPONSIVE — MOBILE (≤ 640px)
   ============================================ */
@media (max-width:640px) {
  :root { --space-3xl:5rem; }

  .nav-links {
    display:none;
    position:fixed;
    top: var(--header-h);
    left:0; right:0;
    background: var(--color-bg);
    flex-direction:column;
    padding: var(--space-md);
    gap:0;
    border-bottom:1px solid var(--color-border);
  }
  .nav-links.active { display:flex; }
  .nav-links a {
    padding: var(--space-sm) 0;
    font-size:1rem;
    border-bottom:1px solid var(--color-border);
  }
  .nav-links a:last-child { border-bottom:none; }
  .nav-toggle { display:block; }

  .hero {
    padding-top: calc(var(--header-h) + var(--space-xl));
    padding-bottom: var(--space-xl);
  }
  .hero-title     { font-size:2rem; }
  .hero-headshot  { height:300px; }
  .section-title  { font-size:1.75rem; }
  .achievements-grid { grid-template-columns:1fr; }
  .connect-grid   { grid-template-columns:1fr; }
  .stats-inner    { grid-template-columns:repeat(2,1fr); gap:var(--space-sm); }
  .stat-number    { font-size:1.5rem; }

  .footer-inner {
    flex-direction:column;
    gap: var(--space-sm);
    text-align:center;
  }
}