:root {
  --bg: #141820;
  --surface: #1a2030;
  --card: #1e2538;
  --border: #2d3548;
  --text: #e2e6ee;
  --text-muted: #8892a6;
  --accent: #5a9cf5;
  --accent-light: #7ab4ff;
  --accent-glow: rgba(90, 156, 245, 0.12);
  --accent-bg: rgba(90, 156, 245, 0.08);
  --grey-accent: #6b7a94;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
  font-family: 'DM Sans', sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  overflow-x: hidden;
}

::selection { background: var(--accent); color: #fff; }
a { color: inherit; text-decoration: none; }

/* ── Nav ── */
nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  padding: 1rem 3rem;
  display: flex; justify-content: flex-end; align-items: center;
  backdrop-filter: blur(16px);
  background: rgba(20,24,32,0.8);
  border-bottom: 1px solid var(--border);
}
.nav-links { display: flex; gap: 2.5rem; list-style: none; }
.nav-links a {
  font-size: 0.82rem; font-weight: 600; color: var(--text-muted);
  letter-spacing: 0.06em; text-transform: uppercase; transition: color 0.3s;
}
.nav-links a:hover { color: var(--accent); }

#lang-toggle {
  background: none; border: 1px solid var(--border); color: var(--accent);
  padding: 0.3rem 0.7rem; border-radius: 6px; font-size: 0.78rem;
  font-weight: 700; cursor: pointer; letter-spacing: 0.06em;
  font-family: 'DM Sans', sans-serif; transition: all 0.3s;
}
#lang-toggle:hover {
  border-color: var(--accent); background: var(--accent-glow);
}

/* ── Hero ── */
.hero {
  min-height: 100vh; display: flex; align-items: center;
  padding: 7rem 3rem 4rem;
  background: linear-gradient(175deg, #181e2e 0%, var(--bg) 50%, #161c28 100%);
}
.hero-grid {
  display: grid; grid-template-columns: 1fr 1fr; gap: 4rem;
  align-items: center; max-width: 1200px; margin: 0 auto; width: 100%;
}
.hero-text h1 {
  font-family: 'Instrument Serif', serif;
  font-size: clamp(2.8rem, 5.5vw, 5rem);
  line-height: 1.08; letter-spacing: -0.03em; margin-bottom: 1.5rem;
}
.hero-text h1 em { font-style: italic; color: var(--accent); }
.hero-subtitle {
  font-size: 1.1rem; color: var(--text-muted); max-width: 460px;
  margin-bottom: 2.5rem; font-weight: 300; line-height: 1.7;
}
.hero-tags { display: flex; flex-wrap: wrap; gap: 0.5rem; }
.hero-tag {
  padding: 0.4rem 0.9rem; border: 1px solid var(--border); border-radius: 100px;
  font-size: 0.76rem; font-weight: 600; color: var(--grey-accent); transition: all 0.3s;
}
.hero-tag:hover { border-color: var(--accent); color: var(--accent); background: var(--accent-glow); }

.hero-visual { display: flex; justify-content: center; position: relative; }
.hero-photo {
  width: 300px; height: 300px; border-radius: 50%; object-fit: cover;
  object-position: center top; border: 3px solid var(--border);
  box-shadow: 0 20px 60px rgba(0,0,0,0.4), 0 0 60px var(--accent-glow);
  animation: photoFloat 6s ease-in-out infinite; position: relative; z-index: 2;
}
@keyframes photoFloat {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}
.hero-photo-wrapper { position: relative; }
.hero-photo-ring {
  position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%);
  width: 350px; height: 350px; border-radius: 50%;
  border: 1.5px solid rgba(90,156,245,0.12);
  animation: ringPulse 4s ease-in-out infinite;
}
.hero-photo-ring:nth-child(2) {
  width: 400px; height: 400px; border-color: rgba(90,156,245,0.06);
  animation-delay: 1.2s;
}
@keyframes ringPulse {
  0%, 100% { transform: translate(-50%,-50%) scale(1); opacity: 1; }
  50% { transform: translate(-50%,-50%) scale(1.03); opacity: 0.4; }
}
.hero-bg-orb {
  position: absolute; width: 400px; height: 400px; border-radius: 50%;
  background: radial-gradient(circle, rgba(90,156,245,0.1), transparent 70%);
  top: 50%; left: 50%; transform: translate(-50%,-50%); z-index: 0;
  filter: blur(40px);
}

/* ── Section ── */
.section { padding: 5rem 3rem; max-width: 1200px; margin: 0 auto; }
.section-label {
  font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.15em;
  color: var(--accent); margin-bottom: 0.75rem; font-weight: 700;
}
.section-title {
  font-family: 'Instrument Serif', serif;
  font-size: clamp(2rem, 3.5vw, 3rem); letter-spacing: -0.02em;
  margin-bottom: 3rem;
}

/* ── Projects Grid ── */
.projects-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 1.5rem; }
.project-card {
  background: var(--card); border: 1px solid var(--border); border-radius: 14px;
  padding: 2rem; position: relative; overflow: hidden;
  transition: all 0.35s cubic-bezier(0.16, 1, 0.3, 1); cursor: pointer;
  text-decoration: none; color: inherit; display: block;
}
.project-card::before {
  content: ''; position: absolute; top: 0; left: 0; right: 0; height: 3px;
  background: linear-gradient(90deg, var(--accent), var(--grey-accent));
  opacity: 0; transition: opacity 0.35s;
}
.project-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 16px 48px rgba(0,0,0,0.3);
  border-color: rgba(90,156,245,0.25);
}
.project-card:hover::before { opacity: 1; }
.project-card:hover .project-arrow { opacity: 1; transform: translateX(0); }

.project-meta { display: flex; align-items: center; gap: 0.75rem; margin-bottom: 1rem; }
.project-company {
  font-size: 0.76rem; font-weight: 700; text-transform: uppercase;
  letter-spacing: 0.08em; color: var(--accent);
}
.project-year {
  font-size: 0.7rem; color: var(--text-muted); padding: 0.2rem 0.55rem;
  border: 1px solid var(--border); border-radius: 4px;
}
.project-title {
  font-family: 'Instrument Serif', serif; font-size: 1.4rem;
  margin-bottom: 0.8rem; line-height: 1.25;
}
.project-desc {
  font-size: 0.88rem; color: var(--text-muted); line-height: 1.7;
  margin-bottom: 1.25rem; font-weight: 300;
}
.project-tech { display: flex; flex-wrap: wrap; gap: 0.4rem; }
.tech-tag {
  padding: 0.25rem 0.65rem; background: var(--accent-bg); border-radius: 5px;
  font-size: 0.7rem; font-weight: 600; color: var(--accent); letter-spacing: 0.02em;
}
.project-footer {
  display: flex; justify-content: space-between; align-items: center; margin-top: 1.25rem;
  padding-top: 1rem; border-top: 1px solid var(--border);
}
.project-cta {
  font-size: 0.78rem; color: var(--accent); font-weight: 600;
  display: flex; align-items: center; gap: 0.4rem;
}
.project-arrow {
  opacity: 0; transform: translateX(-6px); transition: all 0.3s;
  font-size: 1.1rem;
}

/* ── Skills ── */
.skills-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.25rem; }
.skill-group {
  background: var(--card); border: 1px solid var(--border); border-radius: 12px;
  padding: 1.75rem; transition: border-color 0.3s;
}
.skill-group:hover { border-color: var(--accent); }
.skill-group-title {
  font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.12em;
  color: var(--accent); margin-bottom: 1rem; font-weight: 700;
}
.skill-items { display: flex; flex-wrap: wrap; gap: 0.35rem; }
.skill-item {
  padding: 0.3rem 0.65rem; background: rgba(255,255,255,0.04); border-radius: 5px;
  font-size: 0.78rem; color: var(--text-muted); font-weight: 400; transition: all 0.3s;
}
.skill-item:hover { background: var(--accent-glow); color: var(--accent); }

/* ── Contact ── */
.contact-section { text-align: center; padding: 5rem 3rem 7rem; }
.contact-sub { color: var(--text-muted); font-weight: 300; max-width: 420px; margin: 0 auto; }
.contact-links { display: flex; justify-content: center; gap: 1.25rem; margin-top: 2rem; }
.contact-link {
  padding: 0.85rem 1.8rem; border: 1px solid var(--border); border-radius: 100px;
  font-size: 0.85rem; font-weight: 500; transition: all 0.3s;
}
.contact-link:hover { border-color: var(--accent); color: var(--accent); }
.contact-link.primary {
  background: var(--accent); border-color: var(--accent); color: #fff;
}
.contact-link.primary:hover {
  background: var(--accent-light); transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(90,156,245,0.25);
}

footer {
  text-align: center; padding: 2rem 3rem; border-top: 1px solid var(--border);
  font-size: 0.76rem; color: var(--text-muted);
}

/* ── Project Detail Pages ── */
.project-detail {
  display: none; position: fixed; inset: 0; z-index: 200;
  background: var(--bg); overflow-y: auto;
  animation: detailIn 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}
.project-detail.active { display: block; }

@keyframes detailIn {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}

.detail-header {
  padding: 2rem 3rem;
  border-bottom: 1px solid var(--border);
  display: flex; justify-content: space-between; align-items: center;
  position: sticky; top: 0; background: rgba(20,24,32,0.95);
  backdrop-filter: blur(16px); z-index: 10;
}
.detail-back {
  display: flex; align-items: center; gap: 0.5rem; cursor: pointer;
  font-size: 0.85rem; font-weight: 600; color: var(--text-muted);
  transition: color 0.3s; background: none; border: none;
}
.detail-back:hover { color: var(--accent); }
.detail-company {
  font-size: 0.78rem; font-weight: 700; text-transform: uppercase;
  letter-spacing: 0.08em; color: var(--accent);
}

.detail-content {
  max-width: 900px; margin: 0 auto; padding: 3rem;
}
.detail-content h1 {
  font-family: 'Instrument Serif', serif;
  font-size: clamp(2rem, 4vw, 2.8rem); margin-bottom: 0.5rem;
  letter-spacing: -0.02em; line-height: 1.15;
}
.detail-year {
  font-size: 0.85rem; color: var(--text-muted); margin-bottom: 2rem;
}
.detail-section { margin-bottom: 2.5rem; }
.detail-section h2 {
  font-family: 'Instrument Serif', serif; font-size: 1.4rem;
  margin-bottom: 1rem; color: var(--text);
}
.detail-section p {
  font-size: 0.95rem; color: var(--text-muted); line-height: 1.8;
  font-weight: 300;
}
.detail-tech { display: flex; flex-wrap: wrap; gap: 0.5rem; margin-top: 1.5rem; }
.detail-tech .tech-tag { font-size: 0.78rem; padding: 0.35rem 0.85rem; }

.detail-gallery {
  display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 0.75rem;
  margin-top: 1.5rem;
}
.gallery-slot {
  background: var(--card); border: 1px dashed var(--border); border-radius: 8px;
  min-height: 80px; display: flex; align-items: center; justify-content: center;
  flex-direction: column; gap: 0.5rem; color: var(--text-muted);
  font-size: 0.75rem; transition: border-color 0.3s;
}
.gallery-slot:hover { border-color: var(--grey-accent); }
.gallery-slot svg { opacity: 0.4; width: 24px; height: 24px; }
.gallery-slot.full-width { grid-column: span 2; }
.gallery-slot.filled {
  border: 1px solid var(--border); border-style: solid;
  padding: 0; overflow: hidden; min-height: 0;
  width: 100%; height: 100px; background: var(--surface);
}
.gallery-slot.filled img {
  width: 100%; height: 100px; object-fit: cover; display: block;
}

.detail-highlights {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 1rem;
  margin-top: 1.5rem;
}
.highlight-card {
  background: var(--card); border: 1px solid var(--border); border-radius: 10px;
  padding: 1.5rem; text-align: center;
}
.highlight-value {
  font-family: 'Instrument Serif', serif; font-size: 1.8rem; color: var(--accent);
}
.highlight-label {
  font-size: 0.75rem; color: var(--text-muted); margin-top: 0.25rem;
}

.fade-in {
  opacity: 0; transform: translateY(24px);
  transition: all 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}
.fade-in.visible { opacity: 1; transform: translateY(0); }

@media (max-width: 900px) {
  nav { padding: 1rem 1.5rem; }
  .hero { padding: 6rem 1.5rem 3rem; }
  .hero-grid { grid-template-columns: 1fr; gap: 2rem; }
  .hero-visual { display: none; }
  .section { padding: 3.5rem 1.5rem; }
  .projects-grid { grid-template-columns: 1fr; }
  .skills-grid { grid-template-columns: 1fr; }
  .contact-links { flex-direction: column; align-items: center; }
  .detail-content { padding: 2rem 1.5rem; }
  .detail-gallery { grid-template-columns: 1fr; }
  .gallery-slot.full-width { grid-column: span 1; }
  .detail-highlights { grid-template-columns: 1fr; }
}
@media (max-width: 600px) {
  .nav-links { display: none; }
  .hero-text h1 { font-size: 2.4rem; }
}