/* ========================================
   CSS Custom Properties
   ======================================== */
:root {
  --bg: #0d0d0d;
  --bg-alt: #111111;
  --surface: #1a1a1a;
  --border: #242424;
  --text-primary: #f0f0f0;
  --text-secondary: #888;
  --text-muted: #555;
  --accent: #4ade80;
  --accent-dim: rgba(74, 222, 128, 0.12);
  --font-sans:
    "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-mono: "JetBrains Mono", "Fira Code", monospace;
  --nav-h: 64px;
  --radius: 8px;
  --transition: 0.2s ease;
  --max-w: 1100px;
}

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

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

body {
  background-color: var(--bg);
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-weight: 400;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
  -webkit-text-size-adjust: 100%;
}

a {
  color: inherit;
  text-decoration: none;
}

img {
  display: block;
  max-width: 100%;
}

ul {
  list-style: none;
}

button {
  cursor: pointer;
  border: none;
  background: none;
  font-family: inherit;
}

/* ========================================
   Typography Utilities
   ======================================== */
.mono {
  font-family: var(--font-mono);
}

.accent {
  color: var(--accent);
}

/* ========================================
   Layout Utilities
   ======================================== */
.container {
  width: 100%;
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 2rem;
}

/* ========================================
   Buttons
   ======================================== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius);
  font-size: 0.9rem;
  font-weight: 500;
  letter-spacing: 0.02em;
  transition: all var(--transition);
  white-space: nowrap;
}

.btn-primary {
  background-color: var(--accent);
  color: #0d0d0d;
  font-weight: 600;
}

.btn-primary:hover {
  background-color: #6ee7a0;
  transform: translateY(-1px);
}

.btn-ghost {
  background-color: transparent;
  color: var(--text-primary);
  border: 1px solid var(--border);
}

.btn-ghost:hover {
  border-color: var(--accent);
  color: var(--accent);
  transform: translateY(-1px);
}

.btn--large {
  padding: 0.9rem 2rem;
  font-size: 1rem;
}

/* ========================================
   Navbar
   ======================================== */
#navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: var(--nav-h);
  background-color: rgba(13, 13, 13, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition);
}

#navbar.scrolled {
  border-bottom-color: var(--border);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 2rem;
}

.nav-logo {
  font-family: var(--font-mono);
  font-size: 1.2rem;
  font-weight: 500;
  color: var(--text-primary);
  letter-spacing: -0.02em;
  transition: color var(--transition);
}

.nav-logo:hover {
  color: var(--accent);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 2rem;
}

.nav-links a {
  font-size: 0.875rem;
  color: var(--text-secondary);
  transition: color var(--transition);
  font-family: var(--font-mono);
}

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

.nav-github {
  color: var(--text-primary) !important;
  border: 1px solid var(--border);
  padding: 0.35rem 0.75rem;
  border-radius: var(--radius);
  transition:
    border-color var(--transition),
    color var(--transition) !important;
}

.nav-github:hover {
  border-color: var(--accent) !important;
  color: var(--accent) !important;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 4px;
}

.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background-color: var(--text-primary);
  border-radius: 2px;
  transition: all 0.3s ease;
}

/* ========================================
   Section Base
   ======================================== */
.section {
  padding: 7rem 0;
}

.section--alt {
  background-color: var(--bg-alt);
}

.section-header {
  margin-bottom: 3.5rem;
}

.section-label {
  font-size: 0.8rem;
  color: var(--accent);
  letter-spacing: 0.1em;
  text-transform: lowercase;
  display: block;
  margin-bottom: 0.5rem;
}

.section-title {
  font-size: clamp(1.8rem, 3vw, 2.4rem);
  font-weight: 600;
  color: var(--text-primary);
  letter-spacing: -0.03em;
}

/* ========================================
   Hero
   ======================================== */
#hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: calc(var(--nav-h) + 2rem) 2rem 4rem;
  max-width: var(--max-w);
  margin: 0 auto;
  position: relative;
}

.hero-greeting {
  font-size: 1rem;
  color: var(--accent);
  margin-bottom: 0.75rem;
  letter-spacing: 0.05em;
}

.hero-name {
  font-size: clamp(2.5rem, 6vw, 5rem);
  font-weight: 600;
  letter-spacing: -0.04em;
  line-height: 1.05;
  color: var(--text-primary);
  margin-bottom: 0.75rem;
}

.hero-role {
  font-size: clamp(1.1rem, 2.5vw, 1.6rem);
  font-weight: 300;
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
  min-height: 2.5rem;
  font-family: var(--font-mono);
}

.cursor {
  display: inline-block;
  color: var(--accent);
  animation: blink 1s step-end infinite;
  margin-left: 1px;
}

@keyframes blink {
  0%,
  100% {
    opacity: 1;
  }
  50% {
    opacity: 0;
  }
}

.hero-desc {
  font-size: 1.05rem;
  color: var(--text-secondary);
  max-width: 520px;
  line-height: 1.75;
  margin-bottom: 2.5rem;
}

.hero-cta {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.hero-scroll-hint {
  position: absolute;
  bottom: 2.5rem;
  left: 2rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
}

.hero-scroll-hint span {
  font-size: 0.7rem;
  color: var(--text-muted);
  letter-spacing: 0.1em;
  writing-mode: vertical-rl;
}

.scroll-line {
  width: 1px;
  height: 50px;
  background: linear-gradient(to bottom, var(--text-muted), transparent);
  animation: scroll-pulse 2s ease-in-out infinite;
}

@keyframes scroll-pulse {
  0%,
  100% {
    opacity: 0.3;
    transform: scaleY(1);
  }
  50% {
    opacity: 1;
    transform: scaleY(0.6);
  }
}

/* ========================================
   Projects
   ======================================== */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 1.5rem;
}

.project-card {
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: calc(var(--radius) * 1.5);
  overflow: hidden;
  transition:
    border-color 0.25s ease,
    transform 0.25s ease,
    box-shadow 0.25s ease;
}

.project-card:hover {
  border-color: var(--accent);
  transform: translateY(-4px);
  box-shadow: 0 12px 40px rgba(74, 222, 128, 0.08);
}

.project-image-link {
  display: block;
}

.project-image {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background-color: #0a0a0a;
}

.project-image--contain img {
  object-fit: contain;
  padding: 1rem;
}

.project-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s ease;
}

.project-card:hover .project-image img {
  transform: scale(1.04);
}

.project-overlay {
  position: absolute;
  inset: 0;
  background: rgba(13, 13, 13, 0.7);
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transition: opacity 0.25s ease;
}

.project-image-link:hover .project-overlay {
  opacity: 1;
}

.project-overlay span {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--accent);
  letter-spacing: 0.05em;
}

.project-info {
  padding: 1.25rem 1.5rem 1.5rem;
}

.project-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 0.6rem;
}

.project-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  letter-spacing: -0.01em;
}

.project-links {
  display: flex;
  gap: 0.75rem;
  flex-shrink: 0;
}

.project-links a {
  font-size: 1.1rem;
  color: var(--text-muted);
  transition: color var(--transition);
}

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

.project-desc {
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.65;
  margin-bottom: 1rem;
}

.project-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.project-tags li {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--accent);
  background-color: var(--accent-dim);
  padding: 0.2rem 0.65rem;
  border-radius: 4px;
  letter-spacing: 0.02em;
}

/* ========================================
   About
   ======================================== */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: start;
}

.about-text p {
  color: var(--text-secondary);
  font-size: 0.975rem;
  line-height: 1.8;
  margin-bottom: 1.1rem;
}

.about-text strong {
  color: var(--text-primary);
  font-weight: 500;
}

.skills-title {
  font-size: 0.8rem;
  color: var(--accent);
  letter-spacing: 0.1em;
  text-transform: lowercase;
  margin-bottom: 1.25rem;
}

.skills-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.6rem;
}

.skill-item {
  font-size: 0.875rem;
  color: var(--text-secondary);
  padding: 0.6rem 0.875rem;
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-family: var(--font-mono);
  transition:
    border-color var(--transition),
    color var(--transition);
}

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

/* ========================================
   Experience
   ======================================== */
.experience-list {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.exp-card {
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: 2rem;
  padding: 1.75rem 2rem;
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: calc(var(--radius) * 1.5);
  transition: border-color 0.25s ease;
}

.exp-card:hover {
  border-color: var(--accent);
}

.exp-meta {
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
  padding-top: 0.15rem;
}

.exp-period {
  font-size: 0.75rem;
  color: var(--accent);
  letter-spacing: 0.03em;
  white-space: nowrap;
}

.exp-company {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.exp-role {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.75rem;
  letter-spacing: -0.01em;
}

.exp-bullets {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  margin-bottom: 1rem;
}

.exp-bullets li {
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.65;
  padding-left: 1rem;
  position: relative;
}

.exp-bullets li::before {
  content: "▹";
  position: absolute;
  left: 0;
  color: var(--accent);
  font-size: 0.75rem;
  top: 0.15rem;
}

.exp-bullets strong {
  color: var(--text-primary);
  font-weight: 500;
}

.exp-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  list-style: none;
}

.exp-tags li {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--accent);
  background-color: var(--accent-dim);
  padding: 0.2rem 0.65rem;
  border-radius: 4px;
}

/* Certification badge */
.about-cert {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  margin-top: 1.5rem;
  padding: 0.85rem 1rem;
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent);
  border-radius: var(--radius);
}

.cert-badge {
  font-size: 0.85rem;
  color: var(--text-primary);
  font-weight: 500;
}

.cert-date {
  font-size: 0.75rem;
  color: var(--text-muted);
}

/* ========================================
   Certifications
   ======================================== */
.certs-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 1.25rem;
}

.cert-card {
  display: flex;
  align-items: flex-start;
  gap: 1.25rem;
  padding: 1.5rem 1.75rem;
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: calc(var(--radius) * 1.5);
  transition:
    border-color 0.25s ease,
    transform 0.25s ease;
}

.cert-card:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
}

.cert-card-icon {
  font-size: 1.75rem;
  flex-shrink: 0;
  line-height: 1;
  padding-top: 0.15rem;
}

.cert-card-image {
  width: 48px;
  height: 48px;
  object-fit: contain;
  flex-shrink: 0;
}

.cert-card-body {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.cert-card-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  letter-spacing: -0.01em;
}

.cert-card-issuer {
  font-size: 0.78rem;
  color: var(--accent);
  letter-spacing: 0.03em;
}

.cert-card-date {
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-top: 0.15rem;
}

.certs-note {
  margin-top: 1.5rem;
  font-size: 0.875rem;
  color: var(--text-muted);
  font-style: italic;
}

/* ========================================
   Contact
   ======================================== */
.contact-content {
  text-align: center;
  max-width: 560px;
  margin: 0 auto;
}

.contact-desc {
  font-size: 1rem;
  color: var(--text-secondary);
  line-height: 1.75;
  margin-bottom: 2rem;
}

.social-links {
  display: flex;
  justify-content: center;
  gap: 1.5rem;
  margin-top: 2rem;
}

.social-links a {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--text-muted);
  transition: color var(--transition);
  letter-spacing: 0.03em;
}

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

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

#footer p {
  font-size: 0.8rem;
  color: var(--text-muted);
  letter-spacing: 0.02em;
}

/* ========================================
   Scroll Reveal Animations
   ======================================== */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition:
    opacity 0.6s ease,
    transform 0.6s ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* Staggered children */
.projects-grid .reveal:nth-child(2) {
  transition-delay: 0.1s;
}
.projects-grid .reveal:nth-child(3) {
  transition-delay: 0.15s;
}
.projects-grid .reveal:nth-child(4) {
  transition-delay: 0.2s;
}
.projects-grid .reveal:nth-child(5) {
  transition-delay: 0.25s;
}
.projects-grid .reveal:nth-child(6) {
  transition-delay: 0.3s;
}

/* ========================================
   Mobile Nav (open state)
   ======================================== */
#navbar .nav-links.open {
  display: flex;
}

/* ========================================
   Responsive
   ======================================== */
/* ========================================
   Tablet (≤ 900px)
   ======================================== */
@media (max-width: 900px) {
  .about-grid {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }

  .exp-card {
    grid-template-columns: 180px 1fr;
    gap: 1.5rem;
  }
}

/* ========================================
   Mobile (≤ 700px)
   ======================================== */
@media (max-width: 700px) {
  /* Container */
  .container {
    padding: 0 1.25rem;
  }

  /* Nav */
  .nav-inner {
    padding: 0 1.25rem;
  }

  .nav-links {
    display: none;
    position: absolute;
    top: var(--nav-h);
    left: 0;
    right: 0;
    background-color: var(--bg);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    padding: 0.5rem 0;
  }

  .nav-links li {
    width: 100%;
  }

  .nav-links a {
    display: block;
    padding: 0.85rem 1.25rem;
    width: 100%;
    border-radius: 0;
    border: none;
    font-size: 0.95rem;
    min-height: 44px;
  }

  .nav-github {
    border: none !important;
    padding: 0.85rem 1.25rem !important;
  }

  .nav-toggle {
    display: flex;
    min-width: 44px;
    min-height: 44px;
    align-items: center;
    justify-content: center;
  }

  .nav-toggle.open span:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
  }

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

  .nav-toggle.open span:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
  }

  /* Hero */
  #hero {
    min-height: calc(100svh - var(--nav-h));
    padding: calc(var(--nav-h) + 2rem) 1.25rem 3rem;
  }

  .hero-greeting {
    font-size: 0.9rem;
  }

  .hero-name {
    font-size: clamp(2rem, 9vw, 3rem);
    word-break: break-word;
  }

  .hero-role {
    font-size: clamp(0.95rem, 3.5vw, 1.2rem);
    min-height: 2rem;
  }

  .hero-desc {
    font-size: 0.95rem;
    margin-bottom: 2rem;
    max-width: 100%;
  }

  .hero-scroll-hint {
    display: none;
  }

  .hero-cta {
    flex-direction: column;
    align-items: stretch;
    gap: 0.75rem;
  }

  .hero-cta .btn {
    justify-content: center;
    text-align: center;
  }

  /* Sections */
  .section {
    padding: 4rem 0;
  }

  .section-header {
    margin-bottom: 2.5rem;
  }

  /* Projects */
  .projects-grid {
    grid-template-columns: 1fr;
    gap: 1.25rem;
  }

  .project-card:hover {
    transform: none;
  }

  .project-overlay {
    opacity: 1;
    background: linear-gradient(transparent 50%, rgba(13, 13, 13, 0.75));
  }

  .project-overlay span {
    position: absolute;
    bottom: 0.75rem;
    right: 0.75rem;
    font-size: 0.75rem;
  }

  .project-info {
    padding: 1rem 1.25rem 1.25rem;
  }

  .project-desc {
    font-size: 0.85rem;
  }

  /* Experience */
  .exp-card {
    grid-template-columns: 1fr;
    gap: 0.35rem;
    padding: 1.25rem;
  }

  .exp-meta {
    flex-direction: row;
    flex-wrap: wrap;
    align-items: baseline;
    gap: 0.4rem 0.75rem;
  }

  .exp-period {
    font-size: 0.72rem;
  }

  .exp-company {
    font-size: 0.75rem;
  }

  .exp-role {
    font-size: 0.95rem;
    margin-bottom: 0.5rem;
  }

  .exp-bullets li {
    font-size: 0.84rem;
  }

  /* About */
  .about-text p {
    font-size: 0.92rem;
  }

  .skills-grid {
    grid-template-columns: 1fr 1fr;
    gap: 0.5rem;
  }

  .skill-item {
    font-size: 0.8rem;
    padding: 0.55rem 0.65rem;
    text-align: center;
  }

  .about-cert {
    padding: 0.75rem;
  }

  .cert-badge {
    font-size: 0.8rem;
  }

  /* Certifications */
  .certs-grid {
    grid-template-columns: 1fr;
  }

  .cert-card {
    padding: 1.25rem;
    gap: 1rem;
  }

  .cert-card:hover {
    transform: none;
  }

  .cert-card-title {
    font-size: 0.92rem;
  }

  /* Contact */
  .contact-desc {
    font-size: 0.92rem;
  }

  .social-links {
    gap: 1.25rem;
  }

  .social-links a {
    font-size: 0.8rem;
    min-height: 44px;
    display: inline-flex;
    align-items: center;
  }

  /* Buttons */
  .btn {
    min-height: 44px;
    padding: 0.7rem 1.25rem;
  }

  .btn--large {
    width: 100%;
    justify-content: center;
    padding: 0.85rem 1.5rem;
  }
}

/* ========================================
   Small phones (≤ 420px)
   ======================================== */
@media (max-width: 420px) {
  .container {
    padding: 0 1rem;
  }

  .nav-inner {
    padding: 0 1rem;
  }

  #hero {
    padding-left: 1rem;
    padding-right: 1rem;
  }

  .hero-name {
    font-size: clamp(1.75rem, 10vw, 2.5rem);
  }

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

  .exp-card {
    padding: 1rem;
  }

  .exp-bullets li {
    font-size: 0.8rem;
    padding-left: 0.85rem;
  }

  .project-tags li {
    font-size: 0.68rem;
  }

  .social-links {
    flex-direction: column;
    align-items: center;
    gap: 0.75rem;
  }
}