/* ================================================================
   CSS CUSTOM PROPERTIES
   ================================================================ */

:root {
  /* Light theme (default) */
  --bg: #FAFAFA;
  --bg-surface: #FFFFFF;
  --bg-subtle: #F3F4F6;
  --border: #E5E7EB;
  --text: #111827;
  --text-secondary: #6B7280;
  --text-muted: #9CA3AF;
  --accent: #2563EB;
  --accent-bg: #EFF6FF;
  --accent-hover: #1D4ED8;
  --nav-bg: rgba(250, 250, 250, 0.88);
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.08);
  --shadow-hover: 0 8px 24px rgba(0,0,0,0.12);

  /* Layout */
  --nav-h: 64px;
  --container-max: 1100px;
  --section-pad: 48px;

  /* Typography */
  --font-sans: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', 'Consolas', monospace;

  /* Transitions */
  --t: 200ms ease;
  --t-slow: 350ms ease;

  /* Border radius */
  --r-sm: 6px;
  --r-md: 10px;
  --r-lg: 14px;
  --r-full: 9999px;
}

html.dark {
  --bg: #0D1117;
  --bg-surface: #161B22;
  --bg-subtle: #1C2128;
  --border: #30363D;
  --text: #E6EDF3;
  --text-secondary: #8B949E;
  --text-muted: #484F58;
  --accent: #60A5FA;
  --accent-bg: rgba(96, 165, 250, 0.08);
  --accent-hover: #93C5FD;
  --nav-bg: rgba(13, 17, 23, 0.88);
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.3);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.4);
  --shadow-hover: 0 8px 24px rgba(0,0,0,0.6);
}

/* ================================================================
   RESET & BASE
   ================================================================ */

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--text);
  background-color: var(--bg);
  transition: background-color var(--t-slow), color var(--t-slow);
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

a {
  color: var(--accent);
  text-decoration: none;
  transition: color var(--t), opacity var(--t);
}

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

ul, ol { list-style: none; }

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

/* ================================================================
   LAYOUT
   ================================================================ */

.container {
  width: 100%;
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: 1.25rem;
}

/* ================================================================
   SCROLL PROGRESS BAR
   ================================================================ */

#scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: left;
  z-index: 101;
  pointer-events: none;
  transition: transform 0.08s linear;
}

/* ================================================================
   NAVIGATION
   ================================================================ */

.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: var(--nav-h);
  background: var(--nav-bg);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color var(--t), background-color var(--t-slow);
}

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

.nav-container {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  height: 100%;
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: 1.25rem;
}

.nav-brand {
  display: flex;
  align-items: center;
  color: var(--text-secondary);
  transition: color var(--t);
  flex-shrink: 0;
  margin-right: 0.5rem;
  padding: 0.25rem;
  border-radius: var(--r-sm);
}

.nav-brand:hover {
  color: var(--accent);
  background-color: var(--bg-subtle);
}

.nav-links {
  display: none;
  align-items: center;
  gap: 0.125rem;
  flex: 1;
}

.nav-links a {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  padding: 0.375rem 0.625rem;
  border-radius: var(--r-sm);
  transition: color var(--t), background-color var(--t);
}

.nav-links a:hover {
  color: var(--text);
  background-color: var(--bg-subtle);
}

.nav-links a.active {
  color: var(--accent);
  background-color: var(--accent-bg);
}

/* Nav right controls */
.nav-controls {
  display: flex;
  align-items: center;
  gap: 0.375rem;
  margin-left: auto;
  flex-shrink: 0;
}

/* Language toggle */
.lang-toggle {
  display: flex;
  align-items: center;
  border: 1px solid var(--border);
  border-radius: var(--r-full);
  overflow: hidden;
  transition: border-color var(--t);
}

.lang-btn {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-secondary);
  padding: 0.25rem 0.625rem;
  letter-spacing: 0.05em;
  transition: color var(--t), background-color var(--t);
  background: transparent;
  line-height: 1.5;
}

.lang-btn:hover { color: var(--text); background: var(--bg-subtle); }

.lang-btn.active {
  color: var(--accent);
  background: var(--accent-bg);
}

/* Theme toggle */
.theme-toggle {
  width: 34px;
  height: 34px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--r-sm);
  color: var(--text-secondary);
  transition: color var(--t), background-color var(--t);
  flex-shrink: 0;
}

.theme-toggle:hover {
  color: var(--text);
  background-color: var(--bg-subtle);
}

.theme-toggle svg { width: 17px; height: 17px; }

/* Hamburger */
.nav-hamburger {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  border-radius: var(--r-sm);
  color: var(--text-secondary);
  transition: color var(--t), background-color var(--t);
  flex-shrink: 0;
}

.nav-hamburger:hover {
  color: var(--text);
  background-color: var(--bg-subtle);
}

.nav-hamburger svg { width: 20px; height: 20px; }

/* Mobile menu */
.mobile-menu {
  position: fixed;
  top: var(--nav-h);
  left: 0;
  right: 0;
  background: var(--bg-surface);
  border-bottom: 1px solid var(--border);
  z-index: 99;
  padding: 0.75rem 1.25rem 1rem;
  box-shadow: var(--shadow-md);
}

.mobile-menu ul {
  display: flex;
  flex-direction: column;
  gap: 0.125rem;
}

.mobile-menu a {
  display: block;
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--text-secondary);
  padding: 0.625rem 0.75rem;
  border-radius: var(--r-sm);
  transition: color var(--t), background-color var(--t);
}

.mobile-menu a:hover {
  color: var(--text);
  background-color: var(--bg-subtle);
}

/* ================================================================
   SECTIONS BASE
   ================================================================ */

section { padding-block: var(--section-pad); }

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

.section-label {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 2rem;
  font-size: 0; /* reset — children control size */
}

.section-label svg {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
  color: var(--accent);
  opacity: 0.85;
}

.section-label span {
  font-size: 1.75rem;
  font-weight: 600;
  letter-spacing: -0.025em;
  line-height: 1;
  /* Gradient: text colour fading toward accent */
  background: linear-gradient(120deg, var(--text) 40%, var(--accent) 130%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* Location links (hero + contact) */
.location-link {
  color: inherit;
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color var(--t), opacity var(--t);
}

.location-link:hover {
  border-bottom-color: currentColor;
  opacity: 0.8;
  color: inherit;
}

.section-subtitle {
  font-size: 1rem;
  color: var(--text-secondary);
  margin-top: -1.25rem;
  margin-bottom: 2rem;
  max-width: 540px;
}

/* Scroll animation */
.animate-on-scroll {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity 0.55s ease, transform 0.55s ease;
}

.animate-on-scroll.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ================================================================
   HERO
   ================================================================ */

.section-hero {
  position: relative;
  min-height: 100svh;
  display: flex;
  align-items: center;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background-image: radial-gradient(circle, var(--border) 1px, transparent 1px);
  background-size: 26px 26px;
  opacity: 0.6;
  pointer-events: none;
}

.hero-glow {
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse 70% 55% at 0% 5%, var(--accent-bg) 0%, transparent 65%);
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 1;
  padding-block: calc(var(--nav-h) + 2.25rem) 3rem;
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.hero-text {
  flex: 1;
  min-width: 0;
}

.hero-photo {
  flex-shrink: 0;
  width: 96px;
  height: 96px;
  border-radius: 50%;
  overflow: hidden;
  border: 2px solid var(--border);
  background: linear-gradient(135deg, var(--accent-bg), var(--bg-subtle));
  align-self: flex-start;
}

.hero-photo img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center top;
  display: block;
}

.hero-eyebrow {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-bottom: 1.375rem;
}

.hero-eyebrow svg {
  width: 13px;
  height: 13px;
  color: var(--accent);
  flex-shrink: 0;
}

.hero-name {
  font-size: clamp(2.25rem, 6vw, 4.25rem);
  font-weight: 700;
  line-height: 1.08;
  letter-spacing: -0.025em;
  color: var(--text);
  margin-bottom: 1.125rem;
}

.hero-title {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 1.625rem;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--accent);
  background: var(--accent-bg);
  border: 1px solid var(--border);
  padding: 0.3rem 0.75rem;
  border-radius: var(--r-full);
}

.hero-badge-sep {
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--border);
  flex-shrink: 0;
}

.hero-summary {
  font-size: clamp(1rem, 1.5vw, 1.0625rem);
  color: var(--text-secondary);
  line-height: 1.75;
  max-width: 560px;
  margin-bottom: 2.5rem;
}

.hero-ctas {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

@keyframes hero-enter {
  from { opacity: 0; transform: translateY(16px); }
  to   { opacity: 1; transform: translateY(0); }
}

@media (prefers-reduced-motion: no-preference) {
  .hero-photo   { animation: hero-enter 0.5s ease backwards 0.05s; }
  .hero-eyebrow { animation: hero-enter 0.5s ease backwards 0.2s; }
  .hero-name    { animation: hero-enter 0.5s ease backwards 0.3s; }
  .hero-title   { animation: hero-enter 0.5s ease backwards 0.42s; }
  .hero-summary { animation: hero-enter 0.5s ease backwards 0.52s; }
  .hero-ctas    { animation: hero-enter 0.5s ease backwards 0.62s; }
}

/* ================================================================
   BUTTONS
   ================================================================ */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.9375rem;
  font-weight: 500;
  padding: 0.7rem 1.375rem;
  border-radius: var(--r-md);
  transition: all var(--t);
  white-space: nowrap;
  cursor: pointer;
  text-decoration: none;
  line-height: 1.4;
}

.btn svg { width: 16px; height: 16px; flex-shrink: 0; }

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

.btn-primary:hover {
  background: var(--accent-hover);
  border-color: var(--accent-hover);
  color: #fff;
  transform: translateY(-1px);
  box-shadow: 0 4px 14px rgba(37, 99, 235, 0.3);
}

html.dark .btn-primary:hover {
  box-shadow: 0 4px 14px rgba(96, 165, 250, 0.25);
}

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

.btn-ghost:hover {
  background: var(--bg-subtle);
  color: var(--text);
  border-color: var(--text-muted);
  transform: translateY(-1px);
  box-shadow: var(--shadow-sm);
}

/* ================================================================
   ABOUT
   ================================================================ */

.about-body {
  font-size: 1.0625rem;
  line-height: 1.8;
  color: var(--text-secondary);
  max-width: 680px;
}

/* ================================================================
   EXPERTISE
   ================================================================ */

.expertise-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.expertise-tag {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  background: var(--bg-surface);
  border: 1px solid var(--border);
  padding: 0.4375rem 0.875rem;
  border-radius: var(--r-full);
  transition: color var(--t), border-color var(--t), background-color var(--t);
  cursor: default;
}

.expertise-tag:hover {
  color: var(--accent);
  border-color: var(--accent);
  background: var(--accent-bg);
}

/* ================================================================
   TECH STACK
   ================================================================ */

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

.stack-category {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  padding: 1.25rem 1.375rem;
  transition: border-color var(--t), box-shadow var(--t);
}

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

.stack-category:hover {
  border-color: var(--accent);
}

.stack-category-name {
  font-size: 0.6875rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 0.875rem;
}

.stack-items {
  display: flex;
  flex-wrap: wrap;
  gap: 0.375rem;
}

.stack-tag {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--accent);
  background: var(--accent-bg);
  padding: 0.2rem 0.55rem;
  border-radius: var(--r-sm);
  border: 1px solid transparent;
  transition: border-color var(--t);
  line-height: 1.5;
}

.stack-tag:hover { border-color: var(--accent); }

a.stack-tag {
  text-decoration: none;
  cursor: pointer;
}

a.stack-tag:hover {
  border-color: var(--accent);
  background: var(--accent-bg);
  color: var(--accent);
  transform: translateY(-1px);
}

/* ================================================================
   EXPERIENCE / TIMELINE
   ================================================================ */

.timeline {
  position: relative;
  padding-left: 1.375rem;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 0;
  top: 8px;
  bottom: 0;
  width: 1px;
  background: var(--border);
}

.timeline-item {
  position: relative;
  padding-bottom: 1.5rem;
  padding-left: 1.5rem;
}

.timeline-dot {
  position: absolute;
  left: -1.375rem;
  top: 7px;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--border);
  border: 2px solid var(--bg);
  transform: translateX(-3.5px);
  transition: background var(--t);
}

.timeline-item--current .timeline-dot {
  background: var(--accent);
  border-color: var(--bg-surface);
  box-shadow: 0 0 0 3px var(--accent-bg);
}

.timeline-header {
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 0.2rem;
}

.timeline-company {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text);
}

.timeline-period {
  font-size: 0.8125rem;
  color: var(--text-muted);
  margin-left: auto;
  flex-shrink: 0;
}

.timeline-role {
  font-size: 0.9375rem;
  color: var(--accent);
  font-weight: 500;
  margin-bottom: 0.4375rem;
}

.timeline-description {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  line-height: 1.65;
}

/* ================================================================
   LANGUAGES
   ================================================================ */

.lang-list {
  display: flex;
  flex-direction: column;
  gap: 0.875rem;
}

.lang-item {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.lang-name {
  font-size: 1rem;
  font-weight: 500;
  color: var(--text);
  min-width: 76px;
}

.lang-level {
  font-size: 0.6875rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-secondary);
  background: var(--bg-subtle);
  border: 1px solid var(--border);
  padding: 0.2rem 0.625rem;
  border-radius: var(--r-full);
}

/* ================================================================
   CV DOWNLOAD
   ================================================================ */

.cv-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.875rem;
}

.cv-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.625rem;
  text-align: center;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  padding: 1.5rem 1rem 1.375rem;
  color: var(--text-secondary);
  text-decoration: none;
  transition: all var(--t);
}

.cv-card:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-bg);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.cv-card svg {
  width: 26px;
  height: 26px;
  color: var(--text-muted);
  transition: color var(--t);
}

.cv-card:hover svg { color: var(--accent); }

.cv-card-label {
  font-size: 0.875rem;
  font-weight: 500;
  line-height: 1.35;
  color: var(--text);
  transition: color var(--t);
}

.cv-card:hover .cv-card-label { color: var(--accent); }

.cv-card-format {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
  transition: color var(--t);
}

.cv-card:hover .cv-card-format { color: var(--accent); }

/* ================================================================
   CONTACT
   ================================================================ */

.contact-body {
  font-size: 1.0625rem;
  color: var(--text-secondary);
  line-height: 1.75;
  margin-bottom: 2rem;
  max-width: 500px;
}

.contact-meta {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-top: 1.375rem;
}

.contact-meta svg { width: 13px; height: 13px; flex-shrink: 0; }

/* ================================================================
   CONTACT FORM
   ================================================================ */

.contact-form {
  margin-top: 1.75rem;
  padding-top: 1.75rem;
  border-top: 1px solid var(--border);
  margin-bottom: 2rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.375rem;
}

.form-group label {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text);
}

.form-group input,
.form-group textarea {
  -webkit-appearance: none;
  appearance: none;
  font-family: var(--font-sans);
  font-size: 1rem;
  color: var(--text);
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--r-md);
  padding: 0.625rem 0.875rem;
  transition: border-color var(--t), box-shadow var(--t);
  outline: none;
  width: 100%;
  resize: vertical;
  -webkit-text-fill-color: var(--text);
}

.section-alt .form-group input,
.section-alt .form-group textarea {
  background: var(--bg-surface);
}

.form-group input::placeholder,
.form-group textarea::placeholder { color: var(--text-muted); }

.form-group input:-webkit-autofill,
.form-group input:-webkit-autofill:focus {
  -webkit-box-shadow: 0 0 0 1000px var(--bg) inset;
  -webkit-text-fill-color: var(--text);
}

.section-alt .form-group input:-webkit-autofill,
.section-alt .form-group input:-webkit-autofill:focus {
  -webkit-box-shadow: 0 0 0 1000px var(--bg-surface) inset;
}

.form-group input:focus,
.form-group textarea:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-bg);
}

.form-actions {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
  margin-top: 0.25rem;
}

.form-status {
  font-size: 0.875rem;
  color: var(--text-muted);
}

.form-status[data-state="success"] { color: #16a34a; }
.form-status[data-state="error"]   { color: #dc2626; }

.form-submit:disabled { opacity: 0.65; cursor: wait; }

.contact-alt {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
  flex-wrap: wrap;
}

@media (min-width: 640px) {
  .form-row { grid-template-columns: 1fr 1fr; }
}

/* ================================================================
   FOOTER
   ================================================================ */

footer {
  border-top: 1px solid var(--border);
  padding-block: 1.75rem;
  background: var(--bg-surface);
}

.footer-inner {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.footer-name {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text);
}

.footer-copy {
  font-size: 0.8125rem;
  color: var(--text-muted);
}

/* ================================================================
   MEDIA QUERIES — Tablet (640px+)
   ================================================================ */

@media (min-width: 640px) {
  .cv-grid { grid-template-columns: repeat(4, 1fr); }
}

/* ================================================================
   MEDIA QUERIES — Desktop (768px+)
   ================================================================ */

@media (min-width: 768px) {
  :root { --section-pad: 64px; }

  .container { padding-inline: 2rem; }

  .nav-container { padding-inline: 2rem; gap: 0.75rem; }

  .nav-links { display: flex; }

  .nav-hamburger { display: none; }

  /* Hero: side-by-side layout on desktop */
  .hero-content {
    flex-direction: row;
    align-items: center;
    gap: 4rem;
  }

  .hero-photo {
    width: 220px;
    height: 220px;
    order: 1;
    align-self: center;
  }

  .stack-grid { grid-template-columns: repeat(2, 1fr); }

  .timeline { padding-left: 2rem; }

  .timeline-item { padding-left: 2rem; }

  .timeline-dot { left: -2rem; transform: translateX(-4px); }

  .footer-inner {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
  }
}

/* ================================================================
   MEDIA QUERIES — Wide (1024px+)
   ================================================================ */

@media (min-width: 1024px) {
  .stack-grid { grid-template-columns: repeat(3, 1fr); }
}