/* ---------- Tokens ---------- */
:root {
  --bg: #f7f7f5;
  --bg-alt: #ffffff;
  --surface: #ffffff;
  --border: #e4e2dd;
  --text: #1a1a18;
  --text-muted: #5c5a54;
  --accent: #3b5bfd;
  --accent-2: #ff6b3d;
  --shadow: 0 10px 30px -12px rgba(20, 20, 18, 0.12);
  --radius: 16px;
  --font-display: "Space Grotesk", "Inter", system-ui, sans-serif;
  --font-body: "Inter", system-ui, -apple-system, sans-serif;
  --header-h: 76px;
}

:root[data-theme="dark"] {
  --bg: #111113;
  --bg-alt: #0a0a0b;
  --surface: #18181b;
  --border: #2a2a2e;
  --text: #f2f2f0;
  --text-muted: #a1a1a8;
  --shadow: 0 10px 30px -12px rgba(0, 0, 0, 0.5);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #111113;
    --bg-alt: #0a0a0b;
    --surface: #18181b;
    --border: #2a2a2e;
    --text: #f2f2f0;
    --text-muted: #a1a1a8;
    --shadow: 0 10px 30px -12px rgba(0, 0, 0, 0.5);
  }
}

/* ---------- Reset ---------- */
* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  transition: background 0.3s ease, color 0.3s ease;
  overflow-x: hidden;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }
button { font: inherit; cursor: pointer; background: none; border: none; color: inherit; }
.container { max-width: 1080px; margin: 0 auto; padding: 0 24px; }

h1, h2, h3 { font-family: var(--font-display); font-weight: 600; letter-spacing: -0.02em; }

/* ---------- Progress bar ---------- */
.progress-bar {
  position: fixed; top: 0; left: 0; height: 3px; width: 0%;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  z-index: 1000; transition: width 0.1s ease;
}

/* ---------- Header ---------- */
.header {
  position: fixed; top: 0; left: 0; right: 0; z-index: 900;
  height: var(--header-h);
  display: flex; align-items: center;
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s ease;
}
/* backdrop-filter lives on a pseudo-element (not .header itself) so .header
   doesn't become the containing block for its position:fixed nav descendant */
.header::before {
  content: "";
  position: absolute; inset: 0; z-index: -1;
  background: color-mix(in srgb, var(--bg) 80%, transparent);
  backdrop-filter: blur(10px);
  transition: background 0.3s ease;
}
.header.scrolled { border-bottom-color: var(--border); }
.header__inner { display: flex; align-items: center; justify-content: space-between; width: 100%; }

.logo {
  font-family: var(--font-display); font-weight: 700; font-size: 1.3rem;
}
.logo span { color: var(--accent); }

.nav { display: flex; gap: 2rem; }
.nav__link {
  font-size: 0.92rem; font-weight: 500; color: var(--text-muted);
  position: relative; padding: 4px 0;
  transition: color 0.2s ease;
}
.nav__link::after {
  content: ""; position: absolute; left: 0; bottom: -2px; width: 0; height: 2px;
  background: var(--accent); transition: width 0.25s ease;
}
.nav__link:hover { color: var(--text); }
.nav__link:hover::after { width: 100%; }

.header__actions { display: flex; align-items: center; gap: 0.75rem; }

/* Header switches (language + theme) */
.switch {
  position: relative; width: 64px; height: 34px; border-radius: 999px;
  display: flex; align-items: center; justify-content: space-between; padding: 0 10px;
  border: 1px solid var(--border); background: var(--surface); color: var(--text-muted);
  transition: border-color 0.2s ease, background 0.3s ease;
}
.switch:hover { border-color: var(--text-muted); }
.switch:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.switch__label { display: flex; font-size: 0.68rem; font-weight: 700; letter-spacing: 0.04em; }
.switch__label .icon { width: 13px; height: 13px; }
.switch__knob {
  position: absolute; top: 3px; left: 3px; width: 26px; height: 26px; border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  background: var(--bg); color: var(--accent);
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.15), 0 2px 6px rgba(0, 0, 0, 0.12);
}
.switches-ready .switch__knob { transition: transform 0.4s cubic-bezier(0.34, 1.4, 0.64, 1), background 0.3s ease; }
.switch:active .switch__knob { width: 30px; }

/* Theme switch: knob on the right in dark mode */
.switch--theme .switch__knob .icon { width: 15px; height: 15px; }
.switch--theme .switch__knob .icon-moon { display: none; }
:root[data-theme="dark"] .switch--theme .switch__knob { transform: translateX(30px); }
:root[data-theme="dark"] .switch--theme .switch__knob .icon-sun { display: none; }
:root[data-theme="dark"] .switch--theme .switch__knob .icon-moon { display: block; }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .switch--theme .switch__knob { transform: translateX(30px); }
  :root:not([data-theme="light"]) .switch--theme .switch__knob .icon-sun { display: none; }
  :root:not([data-theme="light"]) .switch--theme .switch__knob .icon-moon { display: block; }
}

/* Language switch: knob is the flag, slides right and flips for English */
.switch--lang .switch__knob { background: none; perspective: 200px; }
:root[lang="en"] .switch--lang .switch__knob { transform: translateX(30px); }
.flag-card {
  position: relative; width: 100%; height: 100%;
  transform-style: preserve-3d;
}
.switches-ready .flag-card { transition: transform 0.6s cubic-bezier(0.34, 1.4, 0.64, 1); }
:root[lang="en"] .flag-card { transform: rotateY(180deg); }
.flag {
  position: absolute; inset: 0; width: 100%; height: 100%;
  border-radius: 50%; backface-visibility: hidden;
}
.flag-en { transform: rotateY(180deg); }

/* Text swap on language change (filter, so it doesn't clash with .reveal's opacity) */
.lang-out [data-i18n] { animation: langOut 0.18s ease forwards; }
.lang-in [data-i18n] { animation: langIn 0.3s ease; }
@keyframes langOut { to { filter: opacity(0) blur(3px); } }
@keyframes langIn { from { filter: opacity(0) blur(3px); } }

@media (prefers-reduced-motion: reduce) {
  .switches-ready .switch__knob, .switches-ready .flag-card { transition: none; }
  .lang-out [data-i18n], .lang-in [data-i18n] { animation: none; }
}

.nav-toggle {
  display: none; width: 38px; height: 38px; flex-direction: column;
  justify-content: center; align-items: center; gap: 5px;
}
.nav-toggle span {
  display: block; width: 20px; height: 2px; background: var(--text);
  transition: transform 0.25s ease, opacity 0.25s ease;
}
.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 {
  position: relative;
  min-height: 100vh;
  display: flex; align-items: center;
  padding-top: var(--header-h);
  overflow: hidden;
}
.hero__inner { position: relative; z-index: 1; max-width: 720px; }
.hero__bg {
  position: absolute; inset: 0; z-index: 0; pointer-events: none;
  background:
    radial-gradient(600px circle at 85% 20%, color-mix(in srgb, var(--accent) 18%, transparent), transparent 60%),
    radial-gradient(500px circle at 10% 80%, color-mix(in srgb, var(--accent-2) 14%, transparent), transparent 60%);
}
.hero__eyebrow {
  font-size: 0.85rem; font-weight: 600; letter-spacing: 0.08em; text-transform: uppercase;
  color: var(--accent); margin-bottom: 1rem;
}
.hero__title {
  font-size: clamp(2.4rem, 6vw, 4rem); line-height: 1.05; margin-bottom: 1.25rem;
}
.highlight { color: var(--accent); }
.hero__subtitle {
  font-size: clamp(1.1rem, 2.4vw, 1.4rem); color: var(--text-muted); font-weight: 500;
  margin-bottom: 1rem;
}
.hero__desc {
  font-size: 1.05rem; color: var(--text-muted); max-width: 560px; margin-bottom: 2rem;
}
.hero__cta { display: flex; gap: 1rem; flex-wrap: wrap; margin-bottom: 2.5rem; }

.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 0.85rem 1.6rem; border-radius: 999px; font-weight: 600; font-size: 0.95rem;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease, border-color 0.2s ease;
  border: 1px solid transparent;
}
.btn--primary { background: var(--text); color: var(--bg); }
:root[data-theme="dark"] .btn--primary { background: var(--accent); color: #fff; }
.btn--primary:hover { transform: translateY(-2px); box-shadow: var(--shadow); }
.btn--ghost { border-color: var(--border); color: var(--text); }
.btn--ghost:hover { border-color: var(--text); transform: translateY(-2px); }

.hero__social { display: flex; gap: 1.1rem; }
.hero__social a {
  width: 40px; height: 40px; border-radius: 50%; border: 1px solid var(--border);
  display: flex; align-items: center; justify-content: center;
  color: var(--text-muted); transition: all 0.2s ease;
}
.hero__social a svg { width: 18px; height: 18px; }
.hero__social a:hover { color: var(--accent); border-color: var(--accent); transform: translateY(-2px); }

/* ---------- Sections ---------- */
.section { padding: 7rem 0; }
.section--alt { background: var(--bg-alt); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }
.section__eyebrow {
  font-size: 0.8rem; font-weight: 700; letter-spacing: 0.1em; text-transform: uppercase;
  color: var(--text-muted); margin-bottom: 0.6rem;
}
.section__title { font-size: clamp(1.8rem, 4vw, 2.5rem); margin-bottom: 3rem; }

/* ---------- About ---------- */
.about__grid { display: grid; grid-template-columns: 1.4fr 1fr; gap: 3rem; align-items: start; }
.about__text p { color: var(--text-muted); margin-bottom: 1.1rem; font-size: 1.05rem; }
.about__facts { display: flex; gap: 2.5rem; margin-top: 2rem; }
.fact__num { display: block; font-family: var(--font-display); font-size: 2rem; font-weight: 700; color: var(--accent); }
.fact__label { font-size: 0.85rem; color: var(--text-muted); }

.about__card {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 2rem; text-align: center;
}
.avatar {
  width: 84px; height: 84px; border-radius: 50%; margin: 0 auto 1.5rem;
  display: flex; align-items: center; justify-content: center;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #fff; font-family: var(--font-display); font-weight: 700; font-size: 1.6rem;
}
.about__list { text-align: left; display: flex; flex-direction: column; gap: 0.7rem; }
.about__list li { font-size: 0.92rem; color: var(--text-muted); }
.about__list strong { color: var(--text); }

/* ---------- Timeline (Experience) ---------- */
.timeline { position: relative; padding-left: 2rem; }
.timeline::before {
  content: ""; position: absolute; left: 5px; top: 8px; bottom: 8px; width: 2px;
  background: var(--border);
}
.timeline__item { position: relative; padding-bottom: 2.75rem; }
.timeline__item:last-child { padding-bottom: 0; }
.timeline__dot {
  position: absolute; left: -2rem; top: 4px; width: 12px; height: 12px; border-radius: 50%;
  background: var(--accent); box-shadow: 0 0 0 4px color-mix(in srgb, var(--accent) 18%, transparent);
}
.timeline__date { font-size: 0.82rem; font-weight: 600; color: var(--accent); text-transform: uppercase; letter-spacing: 0.04em; }
.timeline__content h3 { margin: 0.4rem 0 0.3rem; font-size: 1.2rem; }
.timeline__company { color: var(--text-muted); font-weight: 400; }
.timeline__location { font-size: 0.85rem; color: var(--text-muted); margin-bottom: 0.6rem; }
.timeline__content p { color: var(--text-muted); margin-bottom: 0.9rem; max-width: 640px; }
.timeline__tags { display: flex; gap: 0.5rem; flex-wrap: wrap; }
.timeline__tags li {
  font-size: 0.78rem; font-weight: 600; padding: 0.3rem 0.7rem; border-radius: 999px;
  background: var(--surface); border: 1px solid var(--border); color: var(--text-muted);
}

/* ---------- Education ---------- */
.edu-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 1.5rem; }
.edu-card {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 1.75rem; transition: transform 0.25s ease, box-shadow 0.25s ease;
}
.edu-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.edu-card__date {
  font-size: 0.78rem; font-weight: 700; color: var(--accent); text-transform: uppercase; letter-spacing: 0.04em;
}
.edu-card h3 { margin: 0.6rem 0 0.3rem; font-size: 1.05rem; }
.edu-card__org { color: var(--text-muted); font-weight: 500; margin-bottom: 0.7rem; font-size: 0.9rem; }
.edu-card p:last-child { color: var(--text-muted); font-size: 0.92rem; }

/* ---------- Skills ---------- */
.skills-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 2.5rem; }
.skill-cat h3 { font-size: 1.05rem; margin-bottom: 1rem; }
.tag-cloud { display: flex; flex-wrap: wrap; gap: 0.6rem; }
.tag {
  font-size: 0.85rem; font-weight: 600; padding: 0.5rem 1rem; border-radius: 999px;
  background: var(--surface); border: 1px solid var(--border); color: var(--text);
  transition: all 0.2s ease;
}
.tag:hover { border-color: var(--accent); color: var(--accent); transform: translateY(-2px); }

/* ---------- Projects ---------- */
.projects-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.5rem; }
.project-card {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  overflow: hidden; transition: transform 0.25s ease, box-shadow 0.25s ease;
}
.project-card:hover { transform: translateY(-6px); box-shadow: var(--shadow); }
.project-card__img {
  height: 140px;
  background: linear-gradient(135deg, color-mix(in srgb, var(--accent) 25%, var(--surface)), color-mix(in srgb, var(--accent-2) 25%, var(--surface)));
}
.project-card__body { padding: 1.5rem; }
.project-card__body h3 { font-size: 1.05rem; margin-bottom: 0.5rem; }
.project-card__body p { color: var(--text-muted); font-size: 0.92rem; margin-bottom: 1rem; }
.project-card__body .timeline__tags { margin-bottom: 1rem; }
.project-card__link { font-weight: 600; font-size: 0.9rem; color: var(--accent); }

/* ---------- Contact ---------- */
.contact__inner { text-align: center; }
.contact__desc { color: var(--text-muted); max-width: 520px; margin: 0 auto 2rem; font-size: 1.05rem; }
.contact__links { display: flex; justify-content: center; gap: 1rem; flex-wrap: wrap; }

/* ---------- Footer ---------- */
.footer { padding: 2rem 0; }
.footer__inner {
  display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 1rem;
  font-size: 0.85rem; color: var(--text-muted);
}
.footer__top { font-weight: 600; color: var(--text); }

/* ---------- Reveal animation ---------- */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity 0.6s ease, transform 0.6s ease; }
.reveal.is-visible { opacity: 1; transform: translateY(0); }

/* ---------- Responsive ---------- */
@media (max-width: 860px) {
  .about__grid { grid-template-columns: 1fr; }
  .edu-grid { grid-template-columns: 1fr 1fr; }
  .projects-grid { grid-template-columns: 1fr 1fr; }
  .skills-grid { grid-template-columns: 1fr; }
}

@media (max-width: 640px) {
  .nav { position: fixed; top: var(--header-h); left: 0; right: 0; bottom: 0;
    background: var(--bg); flex-direction: column; align-items: center; justify-content: center;
    gap: 2rem; transform: translateX(100%); transition: transform 0.3s ease; z-index: 850;
  }
  .nav.open { transform: translateX(0); }
  .nav__link { font-size: 1.2rem; }
  .nav-toggle { display: flex; }
  .edu-grid, .projects-grid { grid-template-columns: 1fr; }
  .about__facts { gap: 1.5rem; flex-wrap: wrap; }
  .section { padding: 4.5rem 0; }
}