/* ============================================================
   CUSTOM PROPERTIES
   ============================================================ */
:root {
  --bg-primary:    #0d1117;
  --bg-secondary:  #161b22;
  --bg-card:       #1c2128;
  --border:        #30363d;

  --green:         #3fb950;
  --green-dim:     #238636;
  --green-glow:    rgba(63, 185, 80, 0.12);

  --text-primary:  #e6edf3;
  --text-secondary:#8b949e;
  --text-muted:    #484f58;

  --font-sans: 'Segoe UI', system-ui, -apple-system, sans-serif;
  --font-mono: 'Fira Code', 'Cascadia Code', 'Consolas', monospace;

  --radius:   8px;
  --radius-lg:14px;
  --transition: 0.2s ease;

  --container: 1100px;
  --nav-h:     64px;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--nav-h);
}

body {
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--green);
  text-decoration: none;
  transition: color var(--transition);
}

a:hover { color: #58d068; }

ul { list-style: none; }

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

/* ============================================================
   LAYOUT
   ============================================================ */
.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 1.5rem;
}

section {
  padding: 100px 0;
}

.section-title {
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 3rem;
  position: relative;
  display: inline-block;
}

.section-title::after {
  content: '';
  display: block;
  width: 100%;
  height: 2px;
  background: var(--green);
  margin-top: 8px;
  border-radius: 2px;
}

/* ============================================================
   NAVIGATION
   ============================================================ */
header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(13, 17, 23, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  height: var(--nav-h);
}

#navbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 1.5rem;
}

.nav-logo {
  font-family: var(--font-mono);
  font-size: 1rem;
  font-weight: 600;
  color: var(--green);
  letter-spacing: 0.03em;
}

.nav-logo:hover { color: #58d068; }

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

.nav-links a {
  font-size: 0.9rem;
  color: var(--text-secondary);
  font-weight: 500;
  transition: color var(--transition);
}

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

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

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}

/* Hamburger open state */
.nav-toggle[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.nav-toggle[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
}
.nav-toggle[aria-expanded="true"] span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ============================================================
   F1 CAR — top-down roaming
   ============================================================ */
#f1-topdown {
  position: absolute;
  width: 132px;
  height: 56px;
  opacity: 0.18;
  pointer-events: none;
  z-index: 0;
  transform-origin: center center;
  will-change: transform, left, top;
}

/* ============================================================
   HERO
   ============================================================ */
#hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding-top: var(--nav-h);
  position: relative;
  overflow: hidden;
}

/* Subtle grid background */
#hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--border) 1px, transparent 1px),
    linear-gradient(90deg, var(--border) 1px, transparent 1px);
  background-size: 48px 48px;
  opacity: 0.3;
  pointer-events: none;
}

/* Radial green glow — position driven by JS via CSS vars */
#hero::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: radial-gradient(
    600px circle at var(--glow-x, 50%) var(--glow-y, 35%),
    rgba(63, 185, 80, 0.10) 0%,
    transparent 70%
  );
  pointer-events: none;
}

#hero .container { position: relative; z-index: 1; }

.terminal-greeting {
  display: inline-flex;
  align-items: center;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 0.4rem 0.85rem;
  margin-bottom: 1rem;
  font-family: var(--font-mono);
  font-size: 0.95rem;
  color: var(--text-primary);
  max-width: 100%;
}

.terminal-prompt {
  color: var(--green);
  user-select: none;
  flex-shrink: 0;
}

#greeting-text {
  color: var(--text-primary);
  white-space: nowrap;
  overflow: hidden;
}

.terminal-cursor {
  display: inline-block;
  width: 9px;
  height: 1.1em;
  background: var(--green);
  margin-left: 2px;
  vertical-align: text-bottom;
  flex-shrink: 0;
  animation: blink 1s step-end infinite;
}

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

.hero-name {
  font-size: clamp(2.5rem, 7vw, 5rem);
  font-weight: 800;
  line-height: 1.1;
  color: var(--text-primary);
  margin-bottom: 0.5rem;
  letter-spacing: -0.02em;
}

.hero-title {
  font-size: clamp(1.1rem, 3vw, 1.6rem);
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 1rem;
}

.hero-sub {
  font-size: 1rem;
  color: var(--text-muted);
  max-width: 480px;
  margin-bottom: 2.5rem;
}

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

/* ============================================================
   BUTTONS
   ============================================================ */
.btn {
  display: inline-block;
  padding: 0.65rem 1.5rem;
  border-radius: var(--radius);
  font-size: 0.9rem;
  font-weight: 600;
  transition: background var(--transition), color var(--transition), border-color var(--transition), box-shadow var(--transition);
  cursor: pointer;
}

.btn-primary {
  background: var(--green-dim);
  color: #fff;
  border: 1px solid var(--green-dim);
}

.btn-primary:hover {
  background: var(--green);
  border-color: var(--green);
  color: #fff;
  box-shadow: 0 0 18px var(--green-glow);
}

.btn-secondary {
  background: transparent;
  color: var(--green);
  border: 1px solid var(--green-dim);
}

.btn-secondary:hover {
  background: var(--green-glow);
  border-color: var(--green);
  color: var(--green);
}

/* ============================================================
   COPY TOAST
   ============================================================ */
.copy-toast {
  position: fixed;
  bottom: 1.5rem;
  left: 50%;
  transform: translateX(-50%) translateY(0.5rem);
  background: var(--bg-secondary);
  border: 1px solid var(--green-dim);
  color: var(--green);
  font-size: 0.85rem;
  font-weight: 500;
  padding: 0.5rem 1.1rem;
  border-radius: var(--radius);
  box-shadow: 0 4px 16px rgba(0,0,0,0.4);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease, transform 0.2s ease;
  z-index: 9999;
}

.copy-toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* ============================================================
   CONTACT DROPDOWN
   ============================================================ */
.contact-dropdown {
  position: relative;
  display: inline-block;
}

.contact-dropdown-toggle {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
}

.dropdown-caret {
  font-size: 0.75rem;
  transition: transform var(--transition);
}

.contact-dropdown.open .dropdown-caret {
  transform: rotate(180deg);
}

.contact-dropdown-menu {
  display: none;
  position: absolute;
  top: calc(100% + 0.5rem);
  left: 0;
  min-width: 160px;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  list-style: none;
  padding: 0.35rem 0;
  z-index: 100;
  box-shadow: 0 8px 24px rgba(0,0,0,0.4);
}

.contact-dropdown.open .contact-dropdown-menu {
  display: block;
}

.contact-dropdown-menu a,
.contact-dropdown-menu button {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  width: 100%;
  padding: 0.55rem 1rem;
  font-size: 0.875rem;
  color: var(--text-secondary);
  background: none;
  border: none;
  cursor: pointer;
  text-align: left;
  transition: background var(--transition), color var(--transition);
}

.contact-dropdown-menu a:hover,
.contact-dropdown-menu button:hover {
  background: var(--green-glow);
  color: var(--green);
}

/* ============================================================
   ABOUT
   ============================================================ */
#about {
  background: var(--bg-secondary);
}

.about-text p {
  color: var(--text-secondary);
  margin-bottom: 1rem;
  max-width: 680px;
}

.about-text p:last-of-type {
  margin-bottom: 1.75rem;
}

.about-details {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem 2rem;
  border-top: 1px solid var(--border);
  padding-top: 1.25rem;
}

.about-details span {
  font-size: 0.9rem;
  color: var(--text-muted);
}

.about-details strong {
  color: var(--text-secondary);
}

/* ============================================================
   SKILLS
   ============================================================ */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.5rem;
}

.skill-group {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.skill-group:hover {
  border-color: var(--green-dim);
  box-shadow: 0 0 20px var(--green-glow);
}

.skill-group h3 {
  font-size: 0.8rem;
  font-family: var(--font-mono);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--green);
  margin-bottom: 1rem;
}

.skill-group ul {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.skill-group li {
  font-size: 0.9rem;
  color: var(--text-secondary);
  padding-left: 1rem;
  position: relative;
}

.skill-group li::before {
  content: '›';
  position: absolute;
  left: 0;
  color: var(--green);
  font-weight: 700;
}

/* ============================================================
   PROJECTS
   ============================================================ */
#projects {
  background: var(--bg-secondary);
}

.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 1.5rem;
}

.project-card {
  display: flex;
  flex-direction: column;
  cursor: pointer;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  transition: border-color var(--transition), transform var(--transition), box-shadow var(--transition);
}

.project-card:hover {
  border-color: var(--green-dim);
  transform: translateY(-4px);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.4), 0 0 20px var(--green-glow);
}

.project-thumbnail {
  height: 140px;
  background: linear-gradient(135deg, var(--bg-secondary) 0%, #1a2410 100%);
  border-bottom: 1px solid var(--border);
  border-radius: var(--radius-lg) var(--radius-lg) 0 0;
  margin: -1.75rem -1.75rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  position: relative;
}

.project-thumbnail::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--border) 1px, transparent 1px),
    linear-gradient(90deg, var(--border) 1px, transparent 1px);
  background-size: 28px 28px;
  opacity: 0.4;
}

.project-number {
  font-family: var(--font-mono);
  font-size: 3rem;
  font-weight: 700;
  color: var(--green-dim);
  opacity: 0.5;
  position: relative;
  z-index: 1;
  user-select: none;
}

.project-card:hover .project-number { opacity: 0.9; }

.project-info { display: flex; flex-direction: column; flex: 1; }

.project-card h3 {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 0.75rem;
}

.project-card p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.65;
  flex: 1;
  margin-bottom: 1.25rem;
}

.project-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 1.25rem;
}

.project-tags li {
  font-size: 0.75rem;
  font-family: var(--font-mono);
  color: var(--green);
  background: rgba(63, 185, 80, 0.08);
  border: 1px solid rgba(63, 185, 80, 0.2);
  padding: 0.2rem 0.6rem;
  border-radius: 20px;
}

.project-links {
  display: flex;
  gap: 1rem;
  border-top: 1px solid var(--border);
  padding-top: 1rem;
  margin-top: auto;
}

.project-link-icon {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color var(--transition);
}

.project-link-icon:hover { color: var(--green); }

/* ============================================================
   CONTACT
   ============================================================ */
.contact-intro {
  color: var(--text-secondary);
  font-size: 1rem;
  margin-bottom: 2.5rem;
  max-width: 480px;
}

.contact-links {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  max-width: 480px;
}

.contact-item {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1rem 1.25rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text-primary);
  transition: border-color var(--transition), box-shadow var(--transition);
}

.contact-item:hover {
  border-color: var(--green-dim);
  box-shadow: 0 0 16px var(--green-glow);
  color: var(--text-primary);
}

.contact-label {
  font-size: 0.75rem;
  font-family: var(--font-mono);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--green);
  min-width: 60px;
}

.contact-value {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

/* ============================================================
   FOOTER
   ============================================================ */
footer {
  text-align: center;
  padding: 2rem 1.5rem;
  border-top: 1px solid var(--border);
  color: var(--text-muted);
  font-size: 0.85rem;
  font-family: var(--font-mono);
}

/* ============================================================
   RESPONSIVE
   ============================================================ */
@media (max-width: 768px) {
  section { padding: 72px 0; }

  /* Mobile nav */
  .nav-toggle { display: flex; }

  .nav-links {
    position: fixed;
    top: var(--nav-h);
    left: 0;
    right: 0;
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    align-items: center;
    gap: 0;
    padding: 1rem 0;
    /* Hidden by default */
    transform: translateY(-110%);
    opacity: 0;
    pointer-events: none;
    transition: transform 0.25s ease, opacity 0.25s ease;
  }

  .nav-links.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }

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

  .nav-links a {
    display: block;
    padding: 0.85rem 1.5rem;
    font-size: 1rem;
  }

  /* Hero */
  .hero-cta { flex-direction: column; align-items: flex-start; }

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

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

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

  .about-details { flex-direction: column; gap: 0.5rem; }
}