/* ===== THEME VARIABLES ===== */
:root,
[data-theme="dark"] {
  --bg-primary: #0a0a0a;
  --bg-secondary: #111111;
  --bg-card: #141414;
  --bg-card-hover: #1a1a1a;
  --bg-code: #161616;
  --text-primary: #f0ece2;
  --text-secondary: #8a8a8a;
  --text-muted: #4a4a4a;
  --accent: #c9a96e;
  --accent-hover: #dfc08a;
  --accent-subtle: rgba(201, 169, 110, 0.08);
  --border-color: rgba(255, 255, 255, 0.06);
  --border-strong: rgba(255, 255, 255, 0.1);
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 12px 40px rgba(0, 0, 0, 0.5);
  --tag-bg: rgba(255, 255, 255, 0.05);
  --tag-text: #8a8a8a;
  --toggle-bg: #222;
  --toggle-knob: #f0ece2;
  --scrollbar-bg: #0a0a0a;
  --scrollbar-thumb: #2a2a2a;
  --selection-bg: #c9a96e;
  --selection-text: #0a0a0a;
  --link-underline: rgba(201, 169, 110, 0.3);
  --grain-opacity: 0.04;
  --nav-bg: rgba(10, 10, 10, 0.85);
}

[data-theme="light"] {
  --bg-primary: #f5f2eb;
  --bg-secondary: #ebe7de;
  --bg-card: #ffffff;
  --bg-card-hover: #faf8f4;
  --bg-code: #ece9e1;
  --text-primary: #1a1714;
  --text-secondary: #6b6560;
  --text-muted: #a09a94;
  --accent: #8b6914;
  --accent-hover: #a47d1a;
  --accent-subtle: rgba(139, 105, 20, 0.06);
  --border-color: rgba(0, 0, 0, 0.07);
  --border-strong: rgba(0, 0, 0, 0.12);
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 12px 40px rgba(0, 0, 0, 0.08);
  --tag-bg: rgba(0, 0, 0, 0.04);
  --tag-text: #6b6560;
  --toggle-bg: #d8d4cc;
  --toggle-knob: #1a1714;
  --scrollbar-bg: #ebe7de;
  --scrollbar-thumb: #c8c3ba;
  --selection-bg: #8b6914;
  --selection-text: #f5f2eb;
  --link-underline: rgba(139, 105, 20, 0.3);
  --grain-opacity: 0.03;
  --nav-bg: rgba(245, 242, 235, 0.85);
}

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

::selection {
  background: var(--selection-bg);
  color: var(--selection-text);
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: 'Space Grotesk', -apple-system, BlinkMacSystemFont, sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.7;
  transition: background-color 0.6s cubic-bezier(0.4, 0, 0.2, 1),
              color 0.6s cubic-bezier(0.4, 0, 0.2, 1);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

/* ===== GRAIN TEXTURE OVERLAY ===== */
body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 9999;
  opacity: var(--grain-opacity);
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)'/%3E%3C/svg%3E");
  background-repeat: repeat;
  background-size: 200px 200px;
}

/* ===== SCROLLBAR ===== */
::-webkit-scrollbar {
  width: 4px;
}
::-webkit-scrollbar-track {
  background: var(--scrollbar-bg);
}
::-webkit-scrollbar-thumb {
  background: var(--scrollbar-thumb);
  border-radius: 2px;
}

/* ===== TYPOGRAPHY ===== */
h1, h2, h3, h4, h5, h6 {
  font-family: 'Space Grotesk', sans-serif;
  font-weight: 700;
  letter-spacing: -0.04em;
  line-height: 1.1;
  color: var(--text-primary);
}

h1 {
  font-size: clamp(3rem, 8vw, 6rem);
  font-weight: 700;
  letter-spacing: -0.05em;
  line-height: 0.95;
}

h2 {
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  letter-spacing: -0.04em;
}

h3 {
  font-size: clamp(1rem, 2vw, 1.2rem);
  letter-spacing: -0.02em;
}

p {
  color: var(--text-secondary);
  font-size: 1rem;
  line-height: 1.8;
}

a {
  color: var(--text-primary);
  text-decoration: none;
  border-bottom: none;
  transition: color 0.4s ease, opacity 0.4s ease;
}

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

code, .mono {
  font-family: 'JetBrains Mono', 'Fira Code', monospace;
}

/* ===== LAYOUT ===== */
.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 3rem;
}

.section {
  padding: 8rem 0;
  position: relative;
}

.section::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: min(90%, 1040px);
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--border-color) 20%, var(--border-color) 80%, transparent);
}

.section:last-of-type::after {
  display: none;
}

/* ===== NAVIGATION ===== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: var(--nav-bg);
  backdrop-filter: blur(30px) saturate(1.5);
  -webkit-backdrop-filter: blur(30px) saturate(1.5);
  border-bottom: 1px solid var(--border-color);
  transition: background 0.6s ease, border-color 0.6s ease;
}

.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.nav-logo {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 1.4rem;
  font-weight: 700;
  letter-spacing: -0.06em;
  color: var(--text-primary);
  transition: opacity 0.3s ease;
}

.nav-logo:hover {
  opacity: 0.6;
  color: var(--text-primary);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 2.5rem;
  list-style: none;
}

.nav-links a {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--text-muted);
  position: relative;
  padding-bottom: 2px;
  transition: color 0.4s ease;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 1px;
  background: var(--accent);
  transition: width 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

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

.nav-links a:hover::after,
.nav-links a.active::after {
  width: 100%;
}

/* ===== THEME TOGGLE ===== */
.theme-toggle {
  position: relative;
  width: 48px;
  height: 26px;
  background: var(--toggle-bg);
  border: 1px solid var(--border-strong);
  border-radius: 13px;
  cursor: pointer;
  transition: background 0.6s ease, border-color 0.6s ease;
  display: flex;
  align-items: center;
  padding: 0 3px;
}

.theme-toggle::before {
  content: '☀';
  position: absolute;
  left: 6px;
  font-size: 10px;
  opacity: 0.5;
  transition: opacity 0.3s ease;
}

.theme-toggle::after {
  content: '';
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--toggle-knob);
  transition: transform 0.5s cubic-bezier(0.68, -0.15, 0.265, 1.35),
              background 0.6s ease;
  transform: translateX(0);
}

[data-theme="light"] .theme-toggle::before {
  content: '☀';
  opacity: 0;
}

[data-theme="dark"] .theme-toggle::before {
  content: '☾';
  left: auto;
  right: 6px;
  opacity: 0.5;
}

[data-theme="dark"] .theme-toggle::after {
  transform: translateX(22px);
}

/* ===== HERO SECTION ===== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding-top: 72px;
  position: relative;
  overflow: hidden;
}

/* Subtle gradient glow behind hero */
.hero::before {
  content: '';
  position: absolute;
  top: 20%;
  left: 50%;
  transform: translateX(-50%);
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, var(--accent-subtle) 0%, transparent 70%);
  border-radius: 50%;
  pointer-events: none;
  filter: blur(80px);
  opacity: 0.6;
}

.hero-content {
  width: 100%;
  position: relative;
  z-index: 1;
}

.hero-label {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.2em;
  color: var(--accent);
  margin-bottom: 2rem;
  display: flex;
  align-items: center;
  gap: 1rem;
  overflow: hidden;
}

.hero-label::before {
  content: '';
  display: inline-block;
  width: 40px;
  height: 1px;
  background: var(--accent);
  flex-shrink: 0;
}

.hero h1 {
  margin-bottom: 2rem;
  overflow: hidden;
}

/* Text reveal wrapper */
.text-reveal {
  display: inline-block;
  overflow: hidden;
}

.text-reveal-inner {
  display: inline-block;
  transform: translateY(110%);
  transition: transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}

.text-reveal-inner.revealed {
  transform: translateY(0);
}

.hero-description {
  font-size: 1.15rem;
  max-width: 600px;
  margin-bottom: 3rem;
  line-height: 1.9;
  color: var(--text-secondary);
}

.hero-links {
  display: flex;
  gap: 2rem;
  flex-wrap: wrap;
}

.hero-link {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  position: relative;
  padding-bottom: 4px;
  transition: color 0.4s ease;
}

.hero-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 1px;
  background: var(--border-strong);
  transition: background 0.4s ease, transform 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  transform-origin: left;
}

.hero-link:hover {
  color: var(--accent);
}

.hero-link:hover::after {
  background: var(--accent);
  transform: scaleX(1.1);
}

/* ===== SECTION HEADERS ===== */
.section-header {
  margin-bottom: 4rem;
}

.section-label {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.65rem;
  text-transform: uppercase;
  letter-spacing: 0.2em;
  color: var(--accent);
  margin-bottom: 1rem;
  display: flex;
  align-items: center;
  gap: 1rem;
}

.section-label::before {
  content: '';
  display: inline-block;
  width: 24px;
  height: 1px;
  background: var(--accent);
  flex-shrink: 0;
}

/* ===== CARDS ===== */
.card {
  position: relative;
  background: transparent;
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 2rem;
  margin-bottom: 1.25rem;
  transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, var(--accent-subtle), transparent 60%);
  opacity: 0;
  transition: opacity 0.5s ease;
  border-radius: 12px;
}

.card:hover {
  border-color: var(--border-strong);
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.card:hover::before {
  opacity: 1;
}

.card-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 0.75rem;
  gap: 1rem;
  position: relative;
  z-index: 1;
}

.card-title {
  font-size: 1.15rem;
  font-weight: 600;
  letter-spacing: -0.02em;
}

.card-meta {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.65rem;
  color: var(--accent);
  white-space: nowrap;
  letter-spacing: 0.04em;
  font-weight: 600;
  background: linear-gradient(135deg, var(--accent), var(--accent-hover));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.card-description {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-bottom: 1.25rem;
  line-height: 1.7;
  position: relative;
  z-index: 1;
}

.card-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  position: relative;
  z-index: 1;
}

.tag {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.6rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 0.3rem 0.75rem;
  background: var(--tag-bg);
  color: var(--tag-text);
  border-radius: 20px;
  border: 1px solid var(--border-color);
  transition: all 0.3s ease;
}

.card:hover .tag {
  border-color: var(--border-strong);
  color: var(--text-primary);
}

.card-paper-link {
  display: inline-block;
  margin-top: 1rem;
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--accent);
  border-bottom: 1px solid var(--link-underline);
  padding-bottom: 2px;
  position: relative;
  z-index: 1;
  transition: color 0.3s ease, border-color 0.3s ease;
}

.card-paper-link:hover {
  color: var(--accent-hover);
  border-bottom-color: var(--accent-hover);
}

/* ===== SKILLS / LIST STYLE ===== */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 2rem;
}

.skill-group {
  padding: 1.5rem;
  border: 1px solid var(--border-color);
  border-radius: 12px;
  transition: border-color 0.4s ease, transform 0.4s ease;
}

.skill-group:hover {
  border-color: var(--border-strong);
  transform: translateY(-2px);
}

.skill-group h3 {
  font-size: 0.7rem;
  font-family: 'JetBrains Mono', monospace;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  color: var(--accent);
  margin-bottom: 1.25rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--border-color);
}

.skill-group ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.skill-group li {
  font-size: 0.88rem;
  color: var(--text-secondary);
  padding-left: 1.25rem;
  position: relative;
  transition: color 0.3s ease, transform 0.3s ease;
}

.skill-group li::before {
  content: '›';
  position: absolute;
  left: 0;
  color: var(--accent);
  font-size: 0.9rem;
  font-weight: 600;
  transition: transform 0.3s ease;
}

.skill-group:hover li {
  color: var(--text-primary);
}

.skill-group li:hover::before {
  transform: translateX(3px);
}

/* ===== TIMELINE (EXPERIENCE) ===== */
.timeline-item {
  position: relative;
  padding-left: 2.5rem;
  padding-bottom: 3rem;
  border-left: 1px solid var(--border-color);
  transition: border-color 0.3s ease;
}

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

.timeline-item::before {
  content: '';
  position: absolute;
  left: -5px;
  top: 6px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--bg-primary);
  border: 2px solid var(--text-muted);
  transition: all 0.4s ease;
}

.timeline-item:hover {
  border-left-color: var(--accent);
}

.timeline-item:hover::before {
  border-color: var(--accent);
  background: var(--accent);
  box-shadow: 0 0 0 4px var(--accent-subtle);
}

.timeline-header {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-bottom: 0.35rem;
}

.timeline-title {
  font-size: 1.1rem;
  font-weight: 600;
  letter-spacing: -0.02em;
}

.timeline-date {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.65rem;
  color: var(--text-muted);
  letter-spacing: 0.06em;
}

.timeline-subtitle {
  font-size: 0.85rem;
  color: var(--accent);
  margin-bottom: 0.5rem;
  font-style: normal;
  font-family: 'JetBrains Mono', monospace;
  font-weight: 400;
  letter-spacing: 0.02em;
}

.timeline-description {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.8;
}

/* ===== CONTACT / FOOTER ===== */
.contact-links {
  display: flex;
  gap: 2.5rem;
  flex-wrap: wrap;
}

.contact-link {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.8rem;
  color: var(--text-muted);
  letter-spacing: 0.04em;
  position: relative;
  padding-bottom: 4px;
  transition: color 0.4s ease;
}

.contact-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 1px;
  background: var(--border-color);
  transition: background 0.4s ease, transform 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  transform-origin: left;
}

.contact-link:hover {
  color: var(--accent);
}

.contact-link:hover::after {
  background: var(--accent);
}

.footer {
  padding: 3rem 0;
  text-align: center;
  border-top: 1px solid var(--border-color);
}

.footer p {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.65rem;
  color: var(--text-muted);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

/* ===== MOBILE NAV ===== */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.nav-toggle span {
  display: block;
  width: 22px;
  height: 1.5px;
  background: var(--text-primary);
  transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1),
              opacity 0.3s ease;
}

.nav-toggle.active span:nth-child(1) {
  transform: rotate(45deg) translate(4px, 5px);
}

.nav-toggle.active span:nth-child(2) {
  opacity: 0;
}

.nav-toggle.active span:nth-child(3) {
  transform: rotate(-45deg) translate(4px, -5px);
}

/* ===== ANIMATIONS ===== */
.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s cubic-bezier(0.16, 1, 0.3, 1),
              transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

.fade-in:nth-child(2) { transition-delay: 0.1s; }
.fade-in:nth-child(3) { transition-delay: 0.2s; }
.fade-in:nth-child(4) { transition-delay: 0.3s; }
.fade-in:nth-child(5) { transition-delay: 0.4s; }

/* Staggered word reveals for hero */
.word-reveal {
  display: inline-block;
  overflow: hidden;
  vertical-align: bottom;
  padding-bottom: 0.05em;
}

.word-reveal span {
  display: inline-block;
  transform: translateY(105%);
  transition: transform 0.7s cubic-bezier(0.16, 1, 0.3, 1);
}

.word-reveal.revealed span {
  transform: translateY(0);
}

/* Smooth horizontal rule animation */
.hr-anim {
  width: 0;
  height: 1px;
  background: linear-gradient(90deg, var(--accent), transparent);
  border: none;
  transition: width 1.2s cubic-bezier(0.16, 1, 0.3, 1);
  margin: 2rem 0;
}

.hr-anim.visible {
  width: 80px;
}

/* ===== CURSOR GLOW (dark mode only) ===== */
.cursor-glow {
  position: fixed;
  width: 500px;
  height: 500px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(201, 169, 110, 0.04) 0%, transparent 70%);
  pointer-events: none;
  z-index: 0;
  transform: translate(-50%, -50%);
  transition: opacity 0.4s ease;
  opacity: 0;
}

[data-theme="dark"] .cursor-glow {
  opacity: 1;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
  .container {
    padding: 0 1.5rem;
  }

  .section {
    padding: 5rem 0;
  }

  h1 {
    font-size: clamp(2.4rem, 10vw, 3.5rem);
  }

  .nav-toggle {
    display: flex;
  }

  .nav-links {
    position: fixed;
    top: 72px;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--bg-primary);
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 3rem;
    transform: translateX(100%);
    transition: transform 0.5s cubic-bezier(0.65, 0, 0.35, 1);
  }

  .nav-links.open {
    transform: translateX(0);
  }

  .nav-links a {
    font-size: 0.85rem;
  }

  .hero {
    min-height: calc(85vh - 72px);
  }

  .card-header {
    flex-direction: column;
  }

  .timeline-header {
    flex-direction: column;
  }

  .skills-grid {
    grid-template-columns: 1fr 1fr;
  }

  .contact-links {
    flex-direction: column;
    gap: 1.25rem;
  }

  .section-header {
    margin-bottom: 3rem;
  }

  .cursor-glow {
    display: none;
  }
}

@media (max-width: 480px) {
  .skills-grid {
    grid-template-columns: 1fr;
  }

  .hero-links {
    flex-direction: column;
    gap: 1rem;
  }

  .skill-group {
    padding: 1.25rem;
  }
}