/* ---------------------------------------------------------
   Tanye (Xin) Tan — personal site
   Dark / techno design system: black background, blue accent.
--------------------------------------------------------- */

:root {
  --bg: #000000;
  --bg-elevated: #0a0e16;
  --bg-raised: #0f1420;
  --border: #1c2436;
  --text: #eaf0fb;
  --text-muted: #94a1b8;
  --text-faint: #5a6684;
  --accent: #3b82f6;
  --accent-bright: #60a5fa;
  --accent-dim: rgba(59, 130, 246, 0.16);
  --accent-glow: rgba(59, 130, 246, 0.35);
  --mono: "JetBrains Mono", "SFMono-Regular", Consolas, Menlo, monospace;
  --sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --max-width: 980px;
  --radius: 10px;
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background:
    radial-gradient(700px 400px at 12% 0%, rgba(59, 130, 246, 0.10), transparent 60%),
    radial-gradient(600px 500px at 100% 30%, rgba(59, 130, 246, 0.07), transparent 60%),
    var(--bg);
  background-attachment: fixed;
  color: var(--text);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(59, 130, 246, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(59, 130, 246, 0.05) 1px, transparent 1px);
  background-size: 44px 44px;
  mask-image: radial-gradient(ellipse 900px 700px at 20% 0%, black, transparent 70%);
}

::selection {
  background: var(--accent);
  color: #000;
}

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

a.inline-link {
  color: var(--accent-bright);
  border-bottom: 1px solid var(--accent-dim);
}
a.inline-link:hover {
  border-bottom-color: var(--accent-bright);
}

.wrap {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* ---------- nav ---------- */

.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}

.nav .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 56px;
}

.nav-brand {
  font-family: var(--mono);
  font-size: 14px;
  color: var(--text);
}
.nav-brand span {
  color: var(--accent-bright);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 22px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-links a {
  font-family: var(--mono);
  font-size: 13px;
  color: var(--text-muted);
  letter-spacing: 0.02em;
}
.nav-links a:hover {
  color: var(--accent-bright);
}

.nav-toggle {
  display: none;
  background: none;
  border: 1px solid var(--border);
  color: var(--text);
  border-radius: 6px;
  width: 34px;
  height: 34px;
  font-size: 16px;
  cursor: pointer;
}

/* ---------- hero ---------- */

.hero {
  padding: 100px 0 70px;
}

.eyebrow {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--accent-bright);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 20px;
}

.eyebrow::before {
  content: "";
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--accent-bright);
  box-shadow: 0 0 0 3px var(--accent-dim), 0 0 12px var(--accent-glow);
}

.hero-row {
  display: flex;
  align-items: center;
  gap: 26px;
}

.avatar {
  flex: none;
  width: 84px;
  height: 84px;
  border-radius: 50%;
  object-fit: cover;
  border: 1px solid var(--border);
  box-shadow: 0 0 24px rgba(59, 130, 246, 0.18), inset 0 0 0 1px rgba(59, 130, 246, 0.08);
}

.hero h1 {
  margin: 0 0 8px;
  font-size: 38px;
  letter-spacing: -0.01em;
}

.hero .role {
  margin: 0;
  color: var(--text-muted);
  font-size: 16.5px;
}
.hero .role b {
  color: var(--accent-bright);
  font-weight: 600;
}

.hero p.lede {
  max-width: 640px;
  color: var(--text-muted);
  margin-top: 24px;
  font-size: 16px;
}

.cta-row {
  display: flex;
  gap: 12px;
  margin-top: 30px;
  flex-wrap: wrap;
}

.btn {
  font-family: var(--mono);
  font-size: 13px;
  padding: 11px 18px;
  border-radius: 8px;
  border: 1px solid var(--border);
  color: var(--text);
  display: inline-flex;
  align-items: center;
  gap: 8px;
}
.btn.primary {
  background: var(--accent);
  border-color: var(--accent);
  color: #04070d;
  font-weight: 600;
  box-shadow: 0 0 20px rgba(59, 130, 246, 0.35);
}
.btn.primary:hover {
  background: var(--accent-bright);
}
.btn:not(.primary):hover {
  border-color: var(--accent);
  color: var(--accent-bright);
}

.social-row {
  display: flex;
  gap: 18px;
  margin-top: 32px;
  flex-wrap: wrap;
}
.social-row a {
  color: var(--text-muted);
  display: inline-flex;
  align-items: center;
  gap: 7px;
  font-family: var(--mono);
  font-size: 13px;
}
.social-row a:hover {
  color: var(--accent-bright);
}
.social-row svg {
  width: 17px;
  height: 17px;
}

/* ---------- sections ---------- */

section {
  padding: 60px 0;
  border-top: 1px solid var(--border);
}

.section-head {
  display: flex;
  align-items: baseline;
  gap: 10px;
  margin-bottom: 30px;
}

.section-head .index {
  font-family: var(--mono);
  color: var(--accent-bright);
  font-size: 14px;
}

.section-head h2 {
  font-size: 13px;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--text-muted);
  margin: 0;
  font-weight: 600;
}

.section-head .rule {
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, var(--border), transparent);
}

.subhead {
  font-family: var(--mono);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--text-faint);
  margin: 40px 0 16px;
}
.subhead:first-child {
  margin-top: 0;
}

/* ---------- about ---------- */

#about p {
  color: var(--text-muted);
  max-width: 660px;
}
#about p + p {
  margin-top: 14px;
}

.skills {
  margin-top: 30px;
  display: grid;
  gap: 16px;
}

.skill-row {
  display: grid;
  grid-template-columns: 130px 1fr;
  gap: 16px;
  align-items: start;
}

.skill-label {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--text-faint);
  padding-top: 4px;
}

.chip-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.chip {
  font-family: var(--mono);
  font-size: 12px;
  padding: 4px 10px;
  border-radius: 6px;
  border: 1px solid var(--border);
  color: var(--text-muted);
  background: var(--bg-elevated);
}

/* ---------- experience ---------- */

.job {
  display: grid;
  grid-template-columns: 88px 1fr;
  gap: 22px;
  padding: 26px 0;
  border-top: 1px solid var(--border);
}
.job:first-of-type {
  border-top: none;
  padding-top: 0;
}

.job-logo {
  width: 72px;
  height: 72px;
  border-radius: 10px;
  object-fit: contain;
  background: #fff;
  padding: 8px;
  border: 1px solid var(--border);
}

.job-period {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--text-faint);
  padding-top: 2px;
  white-space: nowrap;
}

.job-head {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 6px;
}

.job-title {
  font-size: 17px;
  font-weight: 600;
  margin: 0;
}
.job-title span {
  font-weight: 400;
  color: var(--text-muted);
}

.job-loc {
  color: var(--text-faint);
  font-size: 13px;
  margin: 0 0 10px;
}

.job ul {
  margin: 0;
  padding-left: 18px;
  color: var(--text-muted);
}
.job li {
  margin-bottom: 7px;
  font-size: 14.5px;
}
.job li b {
  color: var(--text);
  font-weight: 600;
}

/* ---------- education / recognition ---------- */

.edu {
  display: grid;
  grid-template-columns: 64px 1fr;
  gap: 18px;
  padding: 18px 0;
  border-top: 1px solid var(--border);
}
.edu:first-of-type {
  border-top: none;
  padding-top: 0;
}
.edu img {
  width: 64px;
  height: 64px;
  border-radius: 10px;
  object-fit: contain;
  background: #fff;
  padding: 8px;
  border: 1px solid var(--border);
}
.edu h3 {
  margin: 0 0 3px;
  font-size: 15.5px;
}
.edu p {
  margin: 0;
  color: var(--text-muted);
  font-size: 13.5px;
}
.edu p.meta {
  margin-top: 4px;
  font-family: var(--mono);
  color: var(--text-faint);
  font-size: 12px;
}
.edu .period {
  font-family: var(--mono);
  color: var(--text-faint);
  font-size: 12px;
}

.list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
}
.list li {
  position: relative;
  padding-left: 20px;
  color: var(--text-muted);
  font-size: 14px;
  line-height: 1.55;
}
.list li::before {
  content: "▸";
  position: absolute;
  left: 0;
  top: 0;
  color: var(--accent-bright);
}
.list .meta {
  color: var(--text-faint);
  font-size: 12.5px;
}

/* ---------- patent ---------- */

.patent {
  display: grid;
  grid-template-columns: 190px 1fr;
  gap: 24px;
  align-items: start;
}
.patent img {
  width: 100%;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  box-shadow: 0 0 30px rgba(59, 130, 246, 0.12);
}
.patent h3 {
  margin: 0 0 8px;
  font-size: 16px;
}
.patent p {
  margin: 0 0 6px;
  color: var(--text-muted);
  font-size: 14px;
}
.patent .meta {
  font-family: var(--mono);
  color: var(--text-faint);
  font-size: 12.5px;
}

/* ---------- projects ---------- */

.project {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 22px;
  background: var(--bg-elevated);
}
.project + .project {
  margin-top: 12px;
}
.project h3 {
  margin: 0 0 6px;
  font-size: 15px;
}
.project p {
  margin: 0;
  color: var(--text-muted);
  font-size: 14px;
}
.project .tags {
  margin-top: 12px;
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

/* ---------- misc ---------- */

.misc-row {
  display: grid;
  grid-template-columns: 130px 1fr;
  gap: 16px;
  padding: 10px 0;
  font-size: 14px;
  color: var(--text-muted);
}
.misc-row .skill-label {
  padding-top: 0;
}
.friends-row {
  color: var(--text-muted);
  line-height: 1.8;
}
.friends-row a {
  color: var(--accent-bright);
}
.friends-row a:hover {
  text-decoration: underline;
}

/* ---------- contact ---------- */

#contact p {
  color: var(--text-muted);
  max-width: 560px;
}

.contact-row {
  margin-top: 24px;
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

footer {
  padding: 36px 0 60px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}
.footer-row {
  color: var(--text-faint);
  font-family: var(--mono);
  font-size: 12px;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 10px;
}
.footer-globe {
  display: flex;
  justify-content: center;
}
.footer-globe img {
  max-width: 200px;
  opacity: 0.9;
}

/* ---------- scroll reveal ---------- */

.reveal {
  opacity: 0;
  transform: translateY(12px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}
.reveal.in {
  opacity: 1;
  transform: none;
}

/* ---------- responsive ---------- */

@media (max-width: 720px) {
  .hero { padding: 80px 0 52px; }
  .hero h1 { font-size: 28px; }
  .hero-row { gap: 16px; }
  .avatar { width: 58px; height: 58px; }
  .nav-links { display: none; }
  .nav-toggle { display: inline-flex; align-items: center; justify-content: center; }
  .job { grid-template-columns: 48px 1fr; gap: 14px; }
  .job-logo { width: 48px; height: 48px; }
  .job-period { white-space: normal; }
  .skill-row { grid-template-columns: 1fr; }
  .edu { grid-template-columns: 44px 1fr; gap: 14px; }
  .edu img { width: 44px; height: 44px; }
  .patent { grid-template-columns: 1fr; }
  .patent img { max-width: 220px; }
  .misc-row { grid-template-columns: 1fr; gap: 4px; }
}

.nav-links.open {
  display: flex;
  position: absolute;
  top: 56px;
  left: 0;
  right: 0;
  background: #000;
  border-bottom: 1px solid var(--border);
  flex-direction: column;
  padding: 16px 24px;
  gap: 16px;
}