/* ==========================================================================
   Design tokens
   ========================================================================== */
:root {
  --bg: #050505;
  --surface: #0d0d0d;
  --surface-raised: #111113;
  --border: #1f1f1f;
  --border-hover: #2c2c2c;
  --text: #f5f5f5;
  --text-secondary: #a1a1aa;
  --text-tertiary: #6b6b70;
  --accent: #00e5ff;
  --accent-dim: rgba(0, 229, 255, 0.12);
  --accent-border: rgba(0, 229, 255, 0.35);

  --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;

  --container: 1120px;
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;

  --nav-height: 72px;

  --ease: cubic-bezier(0.16, 1, 0.3, 1);
  --transition-fast: 180ms var(--ease);
  --transition-base: 320ms var(--ease);
}

/* ==========================================================================
   Reset
   ========================================================================== */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: calc(var(--nav-height) + 16px); }
body, h1, h2, h3, h4, p, figure, blockquote, dl, dd { margin: 0; }
ul, ol { margin: 0; padding: 0; list-style: none; }
img, picture, svg { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; background: none; border: none; cursor: pointer; }
input, textarea { font: inherit; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: 24px;
}

@media (min-width: 768px) {
  .container { padding-inline: 40px; }
}

section {
  padding-block: 96px;
  border-bottom: 1px solid var(--border);
}

@media (max-width: 767px) {
  section { padding-block: 64px; }
}

.section-header {
  max-width: 640px;
  margin-bottom: 48px;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 16px;
}

.section-title {
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 600;
  letter-spacing: -0.02em;
  color: var(--text);
}

.section-subtitle {
  margin-top: 12px;
  color: var(--text-secondary);
  font-size: 17px;
  max-width: 56ch;
}

/* Skip link */
.skip-link {
  position: absolute;
  top: -48px;
  left: 16px;
  background: var(--accent);
  color: #00181c;
  padding: 10px 16px;
  border-radius: var(--radius-sm);
  font-weight: 600;
  z-index: 1000;
  transition: top var(--transition-fast);
}
.skip-link:focus { top: 16px; }

/* Focus states */
a:focus-visible,
button:focus-visible,
input:focus-visible,
textarea:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 4px;
}

/* ==========================================================================
   Scroll reveal
   ========================================================================== */
.reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 700ms var(--ease), transform 700ms var(--ease);
}
.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
}

/* ==========================================================================
   Buttons
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 13px 24px;
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-weight: 600;
  border: 1px solid transparent;
  transition: transform var(--transition-fast), border-color var(--transition-fast),
              background var(--transition-fast), color var(--transition-fast), box-shadow var(--transition-fast);
  white-space: nowrap;
}

.btn-primary {
  background: var(--accent);
  color: #00181c;
}
.btn-primary:hover { box-shadow: 0 0 0 1px var(--accent), 0 8px 24px -8px var(--accent-dim); transform: translateY(-1px); }

.btn-secondary {
  background: transparent;
  color: var(--text);
  border-color: var(--border);
}
.btn-secondary:hover { border-color: var(--border-hover); background: var(--surface-raised); transform: translateY(-1px); }

.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
  padding: 8px 4px;
}
.btn-ghost:hover { color: var(--accent); }

.btn[aria-disabled="true"] {
  opacity: 0.45;
  cursor: not-allowed;
  pointer-events: none;
}

.btn-sm {
  padding: 9px 16px;
  font-size: 13px;
}

/* ==========================================================================
   Navigation
   ========================================================================== */
.site-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: var(--nav-height);
  display: flex;
  align-items: center;
  border-bottom: 1px solid transparent;
  transition: background var(--transition-base), border-color var(--transition-base), backdrop-filter var(--transition-base);
}

.site-nav.is-scrolled {
  background: rgba(5, 5, 5, 0.72);
  backdrop-filter: blur(14px) saturate(140%);
  -webkit-backdrop-filter: blur(14px) saturate(140%);
  border-bottom-color: var(--border);
}

.nav-inner {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: 15px;
  letter-spacing: 0.02em;
}

.nav-links {
  display: none;
  align-items: center;
  gap: 36px;
}

.nav-links a {
  font-size: 14px;
  color: var(--text-secondary);
  transition: color var(--transition-fast);
  position: relative;
}
.nav-links a:hover { color: var(--text); }
.nav-links a[aria-current="page"] { color: var(--text); }

.nav-actions {
  display: flex;
  align-items: center;
  gap: 16px;
}

.nav-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
}

.nav-toggle svg { width: 18px; height: 18px; }
.nav-toggle .icon-close { display: none; }
.nav-toggle[aria-expanded="true"] .icon-open { display: none; }
.nav-toggle[aria-expanded="true"] .icon-close { display: block; }

@media (min-width: 900px) {
  .nav-links { display: flex; }
  .nav-toggle { display: none; }
}

.mobile-menu {
  position: fixed;
  inset: var(--nav-height) 0 0 0;
  background: rgba(5, 5, 5, 0.98);
  backdrop-filter: blur(10px);
  z-index: 99;
  padding: 32px 24px;
  display: flex;
  flex-direction: column;
  gap: 4px;
  transform: translateY(-8px);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-base), transform var(--transition-base);
}

.mobile-menu.is-open {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.mobile-menu a {
  padding: 16px 4px;
  font-size: 22px;
  font-weight: 500;
  border-bottom: 1px solid var(--border);
  color: var(--text);
}

.mobile-menu .btn { margin-top: 24px; align-self: flex-start; }

@media (min-width: 900px) {
  .mobile-menu { display: none; }
}

body.menu-open { overflow: hidden; }

/* ==========================================================================
   Hero
   ========================================================================== */
.hero {
  padding-top: calc(var(--nav-height) + 72px);
  padding-bottom: 96px;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  top: -20%;
  left: 50%;
  transform: translateX(-50%);
  width: 900px;
  height: 500px;
  background: radial-gradient(ellipse at center, var(--accent-dim), transparent 70%);
  pointer-events: none;
  z-index: 0;
}

.hero-inner { position: relative; z-index: 1; max-width: 780px; }

.status-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 7px 14px;
  border: 1px solid var(--border);
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--text-secondary);
  margin-bottom: 28px;
  background: var(--surface);
}

.status-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-dim);
}
.status-dot.is-live { animation: pulse-dot 2.2s ease-in-out infinite; }

@keyframes pulse-dot {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.45; }
}

.hero-name {
  font-size: clamp(40px, 7vw, 68px);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.05;
}

.hero-role {
  margin-top: 18px;
  font-size: clamp(18px, 2.4vw, 22px);
  color: var(--text-secondary);
  font-weight: 500;
}

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

.hero-desc {
  margin-top: 24px;
  font-size: 17px;
  color: var(--text-secondary);
  max-width: 58ch;
}

.hero-ctas {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 40px;
}

/* ==========================================================================
   Featured project (YushaCyber)
   ========================================================================== */
.featured {
  background:
    radial-gradient(ellipse 700px 300px at 20% 0%, var(--accent-dim), transparent 60%),
    var(--surface);
}

.featured-card {
  border: 1px solid var(--accent-border);
  border-radius: var(--radius-lg);
  background: linear-gradient(180deg, rgba(0, 229, 255, 0.04), transparent 40%), var(--bg);
  padding: 48px;
  position: relative;
  overflow: hidden;
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
}

.featured-card:hover {
  border-color: rgba(0, 229, 255, 0.55);
  box-shadow: 0 24px 60px -30px var(--accent-dim);
}

@media (max-width: 640px) {
  .featured-card { padding: 28px 20px; }
}

.featured-label {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 20px;
}

.featured-title {
  font-size: clamp(26px, 4vw, 36px);
  font-weight: 700;
  letter-spacing: -0.02em;
}

.featured-subtitle {
  margin-top: 8px;
  font-size: 18px;
  color: var(--text-secondary);
  font-weight: 500;
}

.featured-desc {
  margin-top: 20px;
  color: var(--text-secondary);
  max-width: 62ch;
  font-size: 16px;
}

.featured-ctas {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 32px;
}

.featured-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 32px;
  margin-top: 40px;
  padding-top: 32px;
  border-top: 1px solid var(--border);
}

.meta-item dt {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-tertiary);
  margin-bottom: 6px;
}

.meta-item dd { font-size: 14px; color: var(--text); margin: 0; }

/* ==========================================================================
   About
   ========================================================================== */
.about-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 48px;
}

@media (min-width: 900px) {
  .about-grid { grid-template-columns: 1.4fr 1fr; }
}

.about-text p {
  color: var(--text-secondary);
  font-size: 17px;
  margin-bottom: 20px;
  max-width: 62ch;
}

.about-text p:first-child {
  color: var(--text);
  font-size: 19px;
}

.about-facts {
  display: flex;
  flex-direction: column;
  gap: 24px;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 28px;
  background: var(--surface);
  height: fit-content;
}

.fact dt {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-tertiary);
  margin-bottom: 6px;
}

.fact dd {
  font-size: 16px;
  color: var(--text);
  margin: 0;
}

/* ==========================================================================
   Tech stack
   ========================================================================== */
.tech-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
}

@media (min-width: 640px) {
  .tech-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (min-width: 1024px) {
  .tech-grid { grid-template-columns: repeat(4, 1fr); }
}

.tech-card {
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 24px;
  background: var(--surface);
  transition: border-color var(--transition-fast), transform var(--transition-fast);
}
.tech-card:hover { border-color: var(--border-hover); transform: translateY(-2px); }

.tech-card h3 {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 16px;
}

.tech-card ul { display: flex; flex-direction: column; gap: 10px; }
.tech-card li { color: var(--text-secondary); font-size: 15px; }

/* ==========================================================================
   Projects
   ========================================================================== */
.project-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
}

@media (min-width: 768px) {
  .project-grid { grid-template-columns: repeat(2, 1fr); }
}

.project-card {
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 28px;
  background: var(--surface);
  display: flex;
  flex-direction: column;
  height: 100%;
  transition: border-color var(--transition-fast), transform var(--transition-fast), box-shadow var(--transition-fast);
}

.project-card:hover {
  border-color: var(--border-hover);
  transform: translateY(-3px);
  box-shadow: 0 20px 40px -28px rgba(0, 0, 0, 0.6);
}

.project-card h3 {
  font-size: 19px;
  font-weight: 600;
  margin-bottom: 10px;
}

.project-card p {
  color: var(--text-secondary);
  font-size: 15px;
  flex-grow: 1;
}

.project-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 18px;
}

.tag {
  font-family: var(--font-mono);
  font-size: 11.5px;
  padding: 4px 10px;
  border-radius: 999px;
  border: 1px solid var(--border);
  color: var(--text-secondary);
}

.project-links {
  display: flex;
  gap: 20px;
  margin-top: 22px;
  padding-top: 20px;
  border-top: 1px solid var(--border);
}

.project-link {
  font-size: 13.5px;
  font-weight: 600;
  color: var(--text-secondary);
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: color var(--transition-fast);
}
.project-link:hover { color: var(--accent); }
.project-link[aria-disabled="true"] {
  opacity: 0.4;
  pointer-events: none;
}

/* ==========================================================================
   Journey (timeline)
   ========================================================================== */
.timeline {
  position: relative;
  max-width: 720px;
}

.timeline-year {
  font-family: var(--font-mono);
  font-size: 15px;
  color: var(--accent);
  margin-bottom: 24px;
  letter-spacing: 0.04em;
}

.timeline-list {
  position: relative;
  border-left: 1px solid var(--border);
  padding-left: 28px;
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.timeline-item {
  position: relative;
  color: var(--text-secondary);
  font-size: 16px;
}

.timeline-item::before {
  content: "";
  position: absolute;
  left: -32.5px;
  top: 8px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--bg);
  border: 2px solid var(--accent);
}

.timeline-item strong { color: var(--text); font-weight: 500; }

/* ==========================================================================
   Blog / Learning in public
   ========================================================================== */
.blog-empty {
  border: 1px dashed var(--border);
  border-radius: var(--radius-md);
  padding: 56px 32px;
  text-align: center;
  background: var(--surface);
}

.blog-empty p {
  font-size: 18px;
  color: var(--text-secondary);
  max-width: 46ch;
  margin-inline: auto;
}

.blog-empty .icon {
  width: 32px;
  height: 32px;
  margin: 0 auto 20px;
  color: var(--accent);
}

/* ==========================================================================
   Now
   ========================================================================== */
.now-list {
  display: flex;
  flex-direction: column;
  gap: 0;
  max-width: 640px;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  overflow: hidden;
  background: var(--surface);
}

.now-item {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 20px 24px;
  font-size: 16px;
  color: var(--text);
  border-bottom: 1px solid var(--border);
}
.now-item:last-child { border-bottom: none; }

.now-item .arrow {
  font-family: var(--font-mono);
  color: var(--accent);
  flex-shrink: 0;
}

/* ==========================================================================
   Resume
   ========================================================================== */
.resume-band {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 36px 40px;
  background: var(--surface);
}

.resume-band h2 { font-size: 22px; font-weight: 600; }
.resume-band p { color: var(--text-secondary); margin-top: 6px; font-size: 15px; }

/* ==========================================================================
   Contact
   ========================================================================== */
.contact-inner { max-width: 640px; }

.contact-links {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  margin-top: 36px;
}

.contact-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 18px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 14px;
  color: var(--text-secondary);
  transition: border-color var(--transition-fast), color var(--transition-fast);
}
.contact-link:hover { border-color: var(--border-hover); color: var(--text); }
.contact-link[aria-disabled="true"] { opacity: 0.4; pointer-events: none; }

/* ==========================================================================
   Footer
   ========================================================================== */
.site-footer {
  padding-block: 48px;
}

.footer-inner {
  display: flex;
  flex-direction: column;
  gap: 28px;
}

@media (min-width: 768px) {
  .footer-inner { flex-direction: row; justify-content: space-between; align-items: flex-end; }
}

.footer-brand {
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: 15px;
}

.footer-tagline {
  color: var(--text-secondary);
  font-size: 14px;
  margin-top: 6px;
}

.footer-links {
  display: flex;
  gap: 24px;
}

.footer-links a {
  font-size: 14px;
  color: var(--text-secondary);
  transition: color var(--transition-fast);
}
.footer-links a:hover { color: var(--accent); }
.footer-links a[aria-disabled="true"] { opacity: 0.4; pointer-events: none; }

.footer-meta {
  margin-top: 24px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 8px;
  font-size: 13px;
  color: var(--text-tertiary);
  font-family: var(--font-mono);
}