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

:root {
  --bg: #faf9f7;
  --surface: #ffffff;
  --text-primary: #1a1a18;
  --text-secondary: #5a5a55;
  --text-muted: #9a9a92;
  --border: #e8e6e0;
  --accent: #2d5016;
  --accent-light: #ebf2e3;
  --accent-mid: #4a7c28;
  --serif: 'DM Serif Display', Georgia, serif;
  --sans: 'DM Sans', system-ui, sans-serif;
  --nav-height: 64px;
  --max-width: 860px;
}

html { scroll-behavior: smooth; }

body {
  font-family: var(--sans);
  background: var(--bg);
  color: var(--text-primary);
  font-size: 16px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

/* NAV */
nav {
  position: fixed; top: 0; left: 0; right: 0;
  height: var(--nav-height);
  background: rgba(250,249,247,0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 max(2rem, calc((100vw - var(--max-width))/2));
  z-index: 100;
}

.nav-logo {
  font-family: var(--serif);
  font-size: 1.1rem;
  color: var(--text-primary);
  text-decoration: none;
  letter-spacing: -0.01em;
}

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

.nav-links a {
  font-size: 0.875rem;
  font-weight: 400;
  color: var(--text-secondary);
  text-decoration: none;
  letter-spacing: 0.01em;
  transition: color 0.2s;
  cursor: pointer;
}

.nav-links a:hover, .nav-links a.active { color: var(--text-primary); }

/* PAGES */
.page { display: none; padding-top: var(--nav-height); min-height: 100vh; }
.page.active { display: block; }

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 2.5rem;
}

/* HOME */
.hero {
  padding: 5rem 0 4rem;
  border-bottom: 1px solid var(--border);
}

.hero-eyebrow {
  font-size: 0.8rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent-mid);
  margin-bottom: 1.25rem;
}

.hero h1 {
  font-family: var(--serif);
  font-size: clamp(2.2rem, 5vw, 3.2rem);
  line-height: 1.15;
  letter-spacing: -0.02em;
  color: var(--text-primary);
  margin-bottom: 1.5rem;
  max-width: 560px;
}

.hero-desc {
  font-size: 1.05rem;
  color: var(--text-secondary);
  max-width: 500px;
  line-height: 1.75;
  margin-bottom: 2rem;
}

.hero-list {
  list-style: none;
  margin-bottom: 2.5rem;
}

.hero-list li {
  font-size: 0.9rem;
  color: var(--text-secondary);
  padding: 0.3rem 0;
  padding-left: 1.2rem;
  position: relative;
}

.hero-list li::before {
  content: '→';
  position: absolute; left: 0;
  color: var(--accent-mid);
  font-size: 0.8rem;
}

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

.btn {
  display: inline-block;
  padding: 0.6rem 1.4rem;
  border-radius: 4px;
  font-size: 0.875rem;
  font-weight: 500;
  text-decoration: none;
  cursor: pointer;
  transition: all 0.18s;
  border: 1px solid transparent;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}
.btn-primary:hover { background: var(--accent-mid); border-color: var(--accent-mid); }

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

/* SECTION */
.section { padding: 3.5rem 0; border-bottom: 1px solid var(--border); }
.section:last-child { border-bottom: none; }

.section-label {
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 1.75rem;
}

.section-title {
  font-family: var(--serif);
  font-size: 1.6rem;
  letter-spacing: -0.02em;
  color: var(--text-primary);
  margin-bottom: 0.75rem;
}

/* WRITING CARDS (home preview) */
.writing-preview { display: flex; flex-direction: column; gap: 0; }

.writing-item {
  display: flex;
  align-items: baseline;
  gap: 1rem;
  padding: 1rem 0;
  border-bottom: 1px solid var(--border);
  cursor: pointer;
  transition: opacity 0.15s;
}
.writing-item:last-child { border-bottom: none; }
.writing-item:hover { opacity: 0.65; }

.writing-date {
  font-size: 0.8rem;
  color: var(--text-muted);
  white-space: nowrap;
  min-width: 70px;
  font-variant-numeric: tabular-nums;
}

.writing-title {
  font-size: 0.95rem;
  color: var(--text-primary);
  font-weight: 400;
}

.writing-tag {
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.05em;
  padding: 2px 8px;
  border-radius: 3px;
  background: var(--accent-light);
  color: var(--accent);
  margin-left: auto;
  white-space: nowrap;
}

.see-all {
  display: inline-block;
  margin-top: 1.5rem;
  font-size: 0.875rem;
  color: var(--accent-mid);
  text-decoration: none;
  cursor: pointer;
  font-weight: 500;
}
.see-all:hover { text-decoration: underline; }

/* RESEARCH PAGE */
.page-header { padding: 4rem 0 2.5rem; border-bottom: 1px solid var(--border); }
.page-header h1 { font-family: var(--serif); font-size: 2.4rem; letter-spacing: -0.02em; }
.page-header p { color: var(--text-secondary); margin-top: 0.75rem; font-size: 1rem; max-width: 520px; }

.research-list { padding: 2rem 0; display: flex; flex-direction: column; gap: 2.5rem; }

.research-card {
  display: grid;
  grid-template-columns: 80px 1fr;
  gap: 1.5rem;
  align-items: start;
}

.research-year {
  font-size: 0.8rem;
  color: var(--text-muted);
  font-variant-numeric: tabular-nums;
  padding-top: 0.15rem;
}

.research-card h3 {
  font-family: var(--serif);
  font-size: 1.05rem;
  font-weight: 400;
  margin-bottom: 0.4rem;
  color: var(--text-primary);
  line-height: 1.4;
}

.research-card p {
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.65;
  margin-bottom: 0.6rem;
}

.tag-row { display: flex; gap: 0.5rem; flex-wrap: wrap; }

.tag {
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  padding: 3px 9px;
  border-radius: 3px;
  border: 1px solid var(--border);
  color: var(--text-secondary);
}

/* WRITING PAGE */
.writing-full { padding: 2rem 0; }

.writing-full-item {
  padding: 2rem 0;
  border-bottom: 1px solid var(--border);
  cursor: pointer;
  transition: opacity 0.15s;
}
.writing-full-item:last-child { border-bottom: none; }
.writing-full-item:hover { opacity: 0.65; }

.writing-meta {
  display: flex; gap: 1rem; align-items: center; margin-bottom: 0.6rem;
}

.writing-meta .date { font-size: 0.8rem; color: var(--text-muted); }

.writing-full-item h3 {
  font-family: var(--serif);
  font-size: 1.2rem;
  font-weight: 400;
  letter-spacing: -0.01em;
  color: var(--text-primary);
  margin-bottom: 0.4rem;
  line-height: 1.35;
}

.writing-full-item p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.65;
  max-width: 540px;
}

/* CONTACT */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2.5rem;
  padding: 2.5rem 0;
}

@media (max-width: 580px) {
  .contact-grid { grid-template-columns: 1fr; }
  .research-card { grid-template-columns: 1fr; gap: 0.25rem; }
}

.contact-block h3 {
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 0.75rem;
}

.contact-block a, .contact-block p {
  font-size: 0.95rem;
  color: var(--text-primary);
  text-decoration: none;
  display: block;
  margin-bottom: 0.3rem;
}
.contact-block a:hover { color: var(--accent-mid); }

.contact-form { padding: 2.5rem 0; }

.form-group { margin-bottom: 1.25rem; }

.form-group label {
  display: block;
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 0.4rem;
  letter-spacing: 0.02em;
}

.form-group input, .form-group textarea {
  width: 100%;
  padding: 0.65rem 0.9rem;
  font-size: 0.9rem;
  font-family: var(--sans);
  color: var(--text-primary);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 4px;
  transition: border-color 0.2s;
  outline: none;
  resize: vertical;
}

.form-group input:focus, .form-group textarea:focus {
  border-color: var(--accent-mid);
}

.form-group textarea { min-height: 120px; }

.form-success {
  display: none;
  padding: 1rem;
  background: var(--accent-light);
  border: 1px solid #c2dba3;
  border-radius: 4px;
  font-size: 0.875rem;
  color: var(--accent);
  margin-top: 1rem;
}

/* FOOTER */
footer {
  border-top: 1px solid var(--border);
  padding: 2rem 0;
  text-align: center;
}

footer p {
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* DIVIDER */
.divider { border: none; border-top: 1px solid var(--border); margin: 0; }

/* PROFILE ROW */
.profile-row {
  display: flex; align-items: center; gap: 1.25rem; margin-bottom: 2rem;
}

.avatar-photo {
  width: 52px; height: 52px; border-radius: 50%;
  border: 2px solid #c2dba3;
  flex-shrink: 0;
  overflow: hidden;
}

.profile-info .name { font-weight: 500; font-size: 0.95rem; }
.profile-info .role { font-size: 0.8rem; color: var(--text-secondary); }

/* PROJECT CARDS */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1rem;
}

.project-card {
  display: flex;
  gap: 1rem;
  align-items: flex-start;
  padding: 1.1rem 1.2rem;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--surface);
  text-decoration: none;
  transition: border-color 0.18s, box-shadow 0.18s;
}
.project-card:hover {
  border-color: #c2dba3;
  box-shadow: 0 2px 12px rgba(45,80,22,0.07);
}

.project-icon {
  width: 36px; height: 36px; border-radius: 8px;
  background: var(--accent-light);
  color: var(--accent);
  font-family: var(--serif);
  font-size: 1rem;
  display: flex; align-items: center; justify-content: center;
  flex-shrink: 0;
  border: 1px solid #c2dba3;
}

.project-name {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: 2px;
}

.project-url {
  font-size: 0.75rem;
  color: var(--accent-mid);
  margin-bottom: 0.4rem;
  font-weight: 400;
}

.project-desc {
  font-size: 0.8rem;
  color: var(--text-secondary);
  line-height: 1.55;
  margin: 0;
}

/* RESEARCH CARD CLICKABLE */
.research-card:hover h3 { color: var(--accent); }

.research-read-more {
  font-size: 0.72rem;
  font-weight: 500;
  color: var(--accent-mid);
  margin-left: auto;
  letter-spacing: 0.03em;
}

/* RESEARCH DETAIL */
.back-link {
  display: inline-block;
  font-size: 0.85rem;
  color: var(--accent-mid);
  cursor: pointer;
  margin-bottom: 1.5rem;
  font-weight: 500;
}
.back-link:hover { text-decoration: underline; }

.research-detail-meta {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 0.75rem;
}

.research-detail-meta span {
  font-size: 0.8rem;
  color: var(--text-muted);
  font-variant-numeric: tabular-nums;
}

.page-header h1#research-detail-title {
  font-size: clamp(1.5rem, 3.5vw, 2.2rem);
  max-width: 640px;
}

.research-detail-body {
  padding: 2.5rem 0;
  max-width: 640px;
}

.research-detail-body p {
  font-size: 1rem;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 1.5rem;
}

.research-detail-body p:last-child { margin-bottom: 0; }

/* ANIMATIONS */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(12px); }
  to   { opacity: 1; transform: translateY(0); }
}

.page.active .container > * {
  animation: fadeUp 0.4s ease both;
}

.page.active .container > *:nth-child(2) { animation-delay: 0.06s; }
.page.active .container > *:nth-child(3) { animation-delay: 0.12s; }
.page.active .container > *:nth-child(4) { animation-delay: 0.18s; }