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

:root {
  /* Palette */
  --c-bg:          #0f1117;
  --c-bg-alt:      #161b27;
  --c-surface:     #1e2535;
  --c-border:      #2a3147;
  --c-accent:      #6c63ff;
  --c-accent-glow: rgba(108, 99, 255, 0.25);
  --c-text:        #e2e8f0;
  --c-text-muted:  #e2e5ec;
  --c-tag-bg:      rgba(108, 99, 255, 0.12);
  --c-tag-text:    #a8a0ff;

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

  /* Spacing scale */
  --s1: 0.5rem;
  --s2: 1rem;
  --s3: 1.5rem;
  --s4: 2rem;
  --s6: 3rem;
  --s8: 4rem;
  --s12: 6rem;

  /* Misc */
  --radius: 12px;
  --radius-sm: 6px;
  --shadow: 0 4px 24px rgba(0,0,0,0.35);
  --transition: 0.2s ease;
}

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

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

img { display: block; max-width: 100%; }
a  { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }
button { cursor: pointer; border: none; background: none; font: inherit; }

/* ─── Layout helpers ──────────────────────────────────────────── */
.container {
  width: min(1100px, 100% - 3rem);
  margin-inline: auto;
}

.section {
  padding-block: var(--s12);
}

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

.section-title {
  font-size: clamp(1.4rem, 4vw, 2rem);
  font-weight: 700;
  margin-bottom: var(--s6);
  position: relative;
  display: inline-block;
}

.section-title::after {
  content: '';
  position: absolute;
  inset-block-end: -8px;
  inset-inline-start: 0;
  width: 40px;
  height: 3px;
  background: var(--c-accent);
  border-radius: 2px;
}

/* ─── Buttons ─────────────────────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--s1);
  padding: 0.65rem 1.4rem;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 0.9rem;
  transition: opacity var(--transition), transform var(--transition), box-shadow var(--transition);
}

.btn:hover { opacity: 0.88; transform: translateY(-1px); }
.btn:active { transform: translateY(0); }

.btn-primary {
  background: var(--c-accent);
  color: #fff;
  box-shadow: 0 0 0 0 var(--c-accent-glow);
}

.btn-primary:hover {
  box-shadow: 0 4px 20px var(--c-accent-glow);
}

.btn-outline {
  border: 1.5px solid var(--c-border);
  color: var(--c-text);
}

.btn-outline:hover {
  border-color: var(--c-accent);
  color: var(--c-accent);
}

.btn-sm { padding: 0.45rem 1rem; font-size: 0.85rem; }

/* ─── Tags ────────────────────────────────────────────────────── */
.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: var(--s1);
  margin-top: var(--s2);
}

.tag {
  background: var(--c-tag-bg);
  color: var(--c-tag-text);
  font-size: 0.78rem;
  font-weight: 500;
  padding: 0.2rem 0.65rem;
  border-radius: 999px;
  border: 1px solid rgba(108,99,255,0.2);
}

/* ─── Nav ─────────────────────────────────────────────────────── */
.nav-header {
  position: fixed;
  inset-block-start: 0;
  inset-inline: 0;
  z-index: 100;
  transition: background var(--transition), backdrop-filter var(--transition), box-shadow var(--transition);
}

.nav-header.scrolled {
  background: rgba(15,17,23,0.85);
  backdrop-filter: blur(12px);
  box-shadow: 0 1px 0 var(--c-border);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-block: var(--s2);
}

.nav-logo {
  font-family: var(--font-mono);
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--c-accent);
  letter-spacing: 0.05em;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--s3);
  font-size: 0.9rem;
  font-weight: 500;
}

.nav-links a:not(.btn) {
  color: var(--c-text-muted);
  transition: color var(--transition);
}

.nav-links a:not(.btn):hover  { color: var(--c-text); }
.nav-links a:not(.btn).active { color: var(--c-accent); }

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

.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--c-text);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}

.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); }

/* ─── Hero ────────────────────────────────────────────────────── */
.hero {
  min-height: 100svh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding-block-start: 80px;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 60% 50% at 70% 40%, rgba(108,99,255,0.12) 0%, transparent 70%),
    radial-gradient(ellipse 40% 40% at 20% 70%, rgba(99,188,255,0.06) 0%, transparent 70%);
  pointer-events: none;
}

.hero-inner {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: var(--s8);
  align-items: center;
}

.hero-greeting {
  font-family: var(--font-mono);
  color: var(--c-accent);
  font-size: 1rem;
  margin-bottom: var(--s1);
}

.hero-name {
  font-size: clamp(2.5rem, 8vw, 5rem);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.02em;
  margin-bottom: var(--s2);
}

.hero-role {
  font-size: clamp(1.1rem, 3vw, 1.6rem);
  color: var(--c-text-muted);
  font-weight: 500;
  margin-bottom: var(--s2);
  min-height: 2em;
}

.role-cycle {
  border-right: 2px solid var(--c-accent);
  padding-right: 4px;
  animation: blink-cursor 0.8s step-end infinite;
}

@keyframes blink-cursor {
  50% { border-color: transparent; }
}

.hero-tagline {
  max-width: 46ch;
  color: var(--c-text-muted);
  font-size: 1.05rem;
  margin-bottom: var(--s4);
}

.hero-cta {
  display: flex;
  gap: var(--s2);
  flex-wrap: wrap;
}

/* Avatar */
.avatar-ring {
  width: 220px;
  height: 220px;
  border-radius: 50%;
  padding: 4px;
  background: linear-gradient(135deg, var(--c-accent), #63bcff);
  box-shadow: 0 0 60px var(--c-accent-glow);
  flex-shrink: 0;
}

.avatar-placeholder {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  background: var(--c-surface);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2.5rem;
  font-weight: 800;
  font-family: var(--font-mono);
  color: var(--c-accent);
  overflow: hidden;
}

.avatar-placeholder img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: 50%;
}

/* Scroll hint */
.scroll-hint {
  position: absolute;
  inset-block-end: var(--s4);
  inset-inline-start: 50%;
  transform: translateX(-50%);
  display: flex;
  align-items: center;
  justify-content: center;
}

.scroll-arrow {
  width: 24px;
  height: 24px;
  border-right: 2px solid var(--c-text-muted);
  border-bottom: 2px solid var(--c-text-muted);
  transform: rotate(45deg);
  animation: bounce 1.8s ease infinite;
  opacity: 0.5;
}

@keyframes bounce {
  0%, 100% { transform: rotate(45deg) translateY(0); }
  50%       { transform: rotate(45deg) translateY(5px); }
}

/* ─── About ───────────────────────────────────────────────────── */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--s6);
  align-items: start;
}

.about-body p + p { margin-top: var(--s2); }
.about-body p     { color: var(--c-text-muted); font-size: 1.05rem; }

.about-facts {
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--radius);
  padding: var(--s3);
  display: flex;
  flex-direction: column;
  gap: var(--s2);
}

.about-facts li {
  display: flex;
  justify-content: space-between;
  gap: var(--s2);
  font-size: 0.95rem;
  padding-bottom: var(--s2);
  border-bottom: 1px solid var(--c-border);
}

.about-facts li:last-child { border-bottom: none; padding-bottom: 0; }

.fact-label { color: var(--c-text-muted); font-weight: 500; }
.fact-value { font-weight: 600; text-align: right; }

/* ─── Skills ──────────────────────────────────────────────────── */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: var(--s3);
}

.skill-group {
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--radius);
  padding: var(--s3);
  transition: border-color var(--transition), transform var(--transition);
}

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

.skill-group-title {
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--c-accent);
  margin-bottom: var(--s2);
}

.skill-list {
  display: flex;
  flex-wrap: wrap;
  gap: var(--s1);
}

.skill-chip {
  background: var(--c-bg);
  border: 1px solid var(--c-border);
  border-radius: var(--radius-sm);
  padding: 0.3rem 0.7rem;
  font-size: 0.88rem;
  font-family: var(--font-mono);
  color: var(--c-text);
  transition: border-color var(--transition), color var(--transition);
}

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

/* ─── Timeline (Experience & Education) ──────────────────────── */
.timeline {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: var(--s4);
}

.timeline::before {
  content: '';
  position: absolute;
  inset-inline-start: 10px;
  inset-block: 0;
  width: 2px;
  background: var(--c-border);
}

.timeline-item {
  position: relative;
  padding-inline-start: var(--s6);
}

.timeline-dot {
  position: absolute;
  inset-inline-start: 5px;
  inset-block-start: 20px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--c-accent);
  box-shadow: 0 0 0 3px var(--c-bg), 0 0 0 5px var(--c-accent);
  z-index: 1;
}

.timeline-card {
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--radius);
  padding: var(--s3);
  transition: border-color var(--transition);
}

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

.timeline-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: var(--s2);
  margin-bottom: var(--s2);
  flex-wrap: wrap;
}

.timeline-role    { font-size: 1.05rem; font-weight: 700; }
.timeline-company { color: var(--c-text-muted); font-size: 0.9rem; margin-top: 2px; }

.timeline-date {
  font-size: 0.82rem;
  font-family: var(--font-mono);
  color: var(--c-accent);
  white-space: nowrap;
  padding: 0.2rem 0.6rem;
  background: var(--c-tag-bg);
  border-radius: var(--radius-sm);
}

.timeline-bullets {
  list-style: disc;
  padding-inline-start: 1.2em;
  font-size: 0.93rem;
  color: var(--c-text-muted);
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.timeline-note {
  font-size: 0.93rem;
  color: var(--c-text-muted);
}

/* ─── Projects ────────────────────────────────────────────────── */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: var(--s3);
}

.project-card {
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--radius);
  padding: var(--s3);
  display: flex;
  flex-direction: column;
  transition: border-color var(--transition), transform var(--transition), box-shadow var(--transition);
}

.project-card:hover {
  border-color: var(--c-accent);
  transform: translateY(-3px);
  box-shadow: 0 8px 32px rgba(108,99,255,0.15);
}

.project-card[data-featured="false"] { display: none; }
.project-card[data-featured="false"].visible { display: flex; }

.project-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--s2);
}

.project-icon { font-size: 1.8rem; }

.project-links {
  display: flex;
  gap: var(--s1);
}

.icon-link {
  color: var(--c-text-muted);
  transition: color var(--transition);
  padding: 4px;
  border-radius: var(--radius-sm);
}

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

.project-title { font-size: 1.1rem; font-weight: 700; margin-bottom: var(--s1); }

.project-desc {
  font-size: 0.93rem;
  color: var(--c-text-muted);
  flex: 1;
}

.projects-toggle-wrap {
  text-align: center;
  margin-top: var(--s4);
}

/* ─── Education & Certs ───────────────────────────────────────── */
.edu-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--s8);
  align-items: start;
}

.cert-list {
  display: flex;
  flex-direction: column;
  gap: var(--s2);
}

.cert-card {
  display: flex;
  gap: var(--s2);
  align-items: center;
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--radius);
  padding: var(--s3);
  transition: border-color var(--transition);
}

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

.cert-badge { font-size: 2rem; flex-shrink: 0; }

.cert-name { font-size: 0.97rem; font-weight: 700; }
.cert-meta { font-size: 0.83rem; color: var(--c-text-muted); margin-top: 2px; }

/* ─── Contact ─────────────────────────────────────────────────── */
.contact-container { max-width: 900px; }

.contact-intro {
  color: var(--c-text-muted);
  font-size: 1.05rem;
  max-width: 50ch;
  margin-bottom: var(--s6);
}

.contact-grid {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: var(--s6);
  align-items: start;
}

/* Form */
.contact-form {
  display: flex;
  flex-direction: column;
  gap: var(--s3);
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.form-group label {
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--c-text-muted);
}

.form-group input,
.form-group textarea {
  background: var(--c-surface);
  border: 1.5px solid var(--c-border);
  border-radius: var(--radius-sm);
  padding: 0.65rem 0.9rem;
  color: var(--c-text);
  font: inherit;
  font-size: 0.95rem;
  transition: border-color var(--transition), box-shadow var(--transition);
  resize: vertical;
}

.form-group input::placeholder,
.form-group textarea::placeholder {
  color: var(--c-text-muted);
  opacity: 0.6;
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--c-accent);
  box-shadow: 0 0 0 3px var(--c-accent-glow);
}

.form-group input.invalid,
.form-group textarea.invalid {
  border-color: #f87171;
}

.form-error {
  font-size: 0.8rem;
  color: #f87171;
  min-height: 1.1em;
}

.form-status {
  font-size: 0.9rem;
  min-height: 1.2em;
}

.form-status.success { color: #4ade80; }
.form-status.error   { color: #f87171; }

/* Contact links */
.contact-links {
  display: flex;
  flex-direction: column;
  gap: var(--s2);
  min-width: 240px;
}

.contact-link {
  display: flex;
  align-items: center;
  gap: var(--s2);
  padding: var(--s2);
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--radius);
  transition: border-color var(--transition), transform var(--transition);
}

.contact-link:hover {
  border-color: var(--c-accent);
  transform: translateX(3px);
}

.contact-link-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  background: var(--c-tag-bg);
  border-radius: var(--radius-sm);
  color: var(--c-accent);
  flex-shrink: 0;
}

.contact-link-label {
  display: block;
  font-size: 0.78rem;
  color: var(--c-text-muted);
  font-weight: 500;
}

.contact-link-value {
  display: block;
  font-size: 0.9rem;
  font-weight: 600;
}

/* ─── Footer ──────────────────────────────────────────────────── */
.footer {
  background: var(--c-bg);
  border-top: 1px solid var(--c-border);
  padding-block: var(--s4);
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.88rem;
  color: var(--c-text-muted);
}

.back-to-top {
  font-size: 1.5rem;
  color: var(--c-text-muted);
  transition: color var(--transition), transform var(--transition);
  line-height: 1;
}

.back-to-top:hover {
  color: var(--c-accent);
  transform: translateY(-2px);
}

/* ─── Scroll-reveal ───────────────────────────────────────────── */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.55s ease, transform 0.55s ease;
}

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

/* ─── Responsive ──────────────────────────────────────────────── */
@media (max-width: 900px) {
  .hero-inner        { grid-template-columns: 1fr; }
  .hero-visual       { display: none; }
  .about-grid        { grid-template-columns: 1fr; }
  .edu-container     { grid-template-columns: 1fr; gap: var(--s6); }
  .contact-grid      { grid-template-columns: 1fr; }
  .contact-links     { min-width: unset; flex-direction: row; flex-wrap: wrap; }
}

@media (max-width: 640px) {
  .nav-links {
    display: none;
    position: fixed;
    inset: 0;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: var(--s4);
    background: var(--c-bg);
    font-size: 1.2rem;
    z-index: 99;
  }

  .nav-links.open { display: flex; }
  .nav-toggle     { display: flex; z-index: 101; }

  .section        { padding-block: var(--s8); }
  .timeline::before { display: none; }
  .timeline-item  { padding-inline-start: 0; }
  .timeline-dot   { display: none; }
  .projects-grid  { grid-template-columns: 1fr; }
  .skills-grid    { grid-template-columns: 1fr 1fr; }
  .footer-inner   { flex-direction: column; gap: var(--s2); text-align: center; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
  html { scroll-behavior: auto; }
}