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

:root {
  --bg: #0c0e12;
  --bg-elevated: #141820;
  --surface: #1a1f2b;
  --border: rgba(255, 255, 255, 0.08);
  --text: #e8eaef;
  --text-muted: #8b92a5;
  --accent: #e8a87c;
  --accent-soft: rgba(232, 168, 124, 0.15);
  --font-sans: "DM Sans", "Noto Sans TC", system-ui, sans-serif;
  --radius: 12px;
  --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

html {
  scroll-behavior: smooth;
}

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

a {
  color: inherit;
  text-decoration: none;
}

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

.container {
  width: min(1080px, 92vw);
  margin-inline: auto;
}

/* ── Header ── */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 1.25rem 0;
  background: rgba(12, 14, 18, 0.75);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition);
}

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

.nav {
  width: min(1080px, 92vw);
  margin-inline: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  font-weight: 700;
  font-size: 1.1rem;
  letter-spacing: -0.02em;
}

.nav-links {
  display: flex;
  gap: 2rem;
  list-style: none;
}

.nav-links a {
  font-size: 0.9rem;
  color: var(--text-muted);
  transition: color var(--transition);
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--accent);
}

.nav-links a.active {
  font-weight: 500;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 6px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

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

/* ── Hero ── */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding: 8rem 0 6rem;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 60% 50% at 70% 20%, rgba(232, 168, 124, 0.12), transparent),
    radial-gradient(ellipse 50% 40% at 20% 80%, rgba(100, 140, 200, 0.08), transparent);
  pointer-events: none;
}

.hero-content {
  position: relative;
}

.hero-label {
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  color: var(--accent);
  margin-bottom: 1rem;
}

.hero-title {
  font-size: clamp(3rem, 10vw, 5.5rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.05;
  margin-bottom: 1.5rem;
}

.hero-tagline {
  font-size: clamp(1rem, 2.5vw, 1.25rem);
  color: var(--text-muted);
  max-width: 32ch;
  margin-bottom: 2.5rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  padding: 0.75rem 1.75rem;
  border-radius: 999px;
  font-size: 0.95rem;
  font-weight: 500;
  transition: background var(--transition), color var(--transition), border-color var(--transition);
}

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

.btn-primary:hover {
  background: #f0b88e;
}

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

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

.scroll-hint {
  position: absolute;
  bottom: 2.5rem;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  animation: float 2.5s ease-in-out infinite;
}

@keyframes float {
  0%, 100% { transform: translateX(-50%) translateY(0); }
  50% { transform: translateX(-50%) translateY(6px); }
}

/* ── Sections ── */
.section {
  padding: 6rem 0;
}

.section-header {
  margin-bottom: 3rem;
}

.section-label {
  display: block;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--accent);
  margin-bottom: 0.5rem;
}

.section-header h2 {
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  font-weight: 700;
  letter-spacing: -0.02em;
}

/* ── About ── */
.about-grid {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 3rem;
  align-items: start;
}

.about-text p {
  color: var(--text-muted);
  margin-bottom: 1.25rem;
  max-width: 55ch;
}

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

.about-tags {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.about-tags li {
  padding: 0.5rem 1rem;
  background: var(--accent-soft);
  border: 1px solid rgba(232, 168, 124, 0.25);
  border-radius: 999px;
  font-size: 0.85rem;
  color: var(--accent);
  white-space: nowrap;
}

/* ── Projects ── */
.project-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
}

.project-card {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 2rem;
  transition: border-color var(--transition), transform var(--transition);
}

.project-card:hover {
  border-color: rgba(232, 168, 124, 0.35);
  transform: translateY(-4px);
}

.project-card--link {
  display: block;
  color: inherit;
  cursor: pointer;
}

.project-number {
  font-size: 0.8rem;
  color: var(--accent);
  font-weight: 600;
  margin-bottom: 1rem;
}

.project-card h3 {
  font-size: 1.25rem;
  margin-bottom: 0.75rem;
}

.project-card p {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 1.5rem;
}

.project-tag {
  display: inline-block;
  font-size: 0.75rem;
  padding: 0.25rem 0.75rem;
  background: var(--surface);
  border-radius: 999px;
  color: var(--text-muted);
}

/* ── Contact ── */
.contact-box {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 2.5rem;
}

.contact-box > p {
  color: var(--text-muted);
  margin-bottom: 2rem;
  max-width: 50ch;
}

.contact-links {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.contact-link {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  padding: 1.25rem 1.5rem;
  background: var(--surface);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  transition: border-color var(--transition), background var(--transition);
}

.contact-link:hover {
  border-color: rgba(232, 168, 124, 0.4);
  background: var(--accent-soft);
}

.contact-link-label {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-muted);
}

.contact-link-value {
  font-size: 1.05rem;
  font-weight: 500;
}

/* ── Footer ── */
.site-footer {
  padding: 2rem 0;
  border-top: 1px solid var(--border);
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.back-to-top {
  transition: color var(--transition);
}

.back-to-top:hover {
  color: var(--accent);
}

/* ── Subpages ── */
.page-main {
  min-height: 100vh;
  padding: 8rem 0 4rem;
}

.page-content {
  max-width: 640px;
}

.page-content--wide {
  max-width: none;
}

.page-content--wide .project-grid {
  margin-bottom: 2.5rem;
}

.testing-page {
  text-align: center;
  padding-top: 2rem;
}

.testing-badge {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
  background: var(--accent-soft);
  border: 1px solid rgba(232, 168, 124, 0.25);
  border-radius: 999px;
  padding: 0.3rem 0.85rem;
  margin-bottom: 1.25rem;
}

.testing-page .page-lead {
  max-width: 42ch;
  margin-inline: auto;
}

.testing-page .back-home {
  margin-top: 2rem;
}

.page-label {
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  color: var(--accent);
  margin-bottom: 1rem;
}

.page-title {
  font-size: clamp(2rem, 6vw, 3rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 1.5rem;
}

.page-lead,
.page-body p {
  color: var(--text-muted);
  margin-bottom: 1.25rem;
  line-height: 1.8;
}

.page-body strong {
  color: var(--text);
  font-weight: 500;
}

.page-tags {
  flex-direction: row;
  flex-wrap: wrap;
  margin-bottom: 2.5rem;
}

.back-home {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--accent);
  padding: 0.6rem 1.25rem;
  border: 1px solid rgba(232, 168, 124, 0.35);
  border-radius: 999px;
  transition: background var(--transition), border-color var(--transition);
}

.back-home:hover {
  background: var(--accent-soft);
  border-color: var(--accent);
}

/* ── QR Branch (/3) ── */
.qr-branch {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background:
    radial-gradient(ellipse 70% 50% at 50% -10%, rgba(232, 168, 124, 0.1), transparent),
    var(--bg);
}

.qr-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.25rem min(4vw, 1.5rem);
  border-bottom: 1px solid var(--border);
}

.qr-breadcrumb {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.9rem;
  font-family: "DM Sans", monospace, sans-serif;
}

.qr-breadcrumb a {
  color: var(--text-muted);
  transition: color var(--transition);
}

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

.qr-breadcrumb-sep {
  color: var(--text-muted);
  opacity: 0.5;
}

.qr-breadcrumb-current {
  color: var(--accent);
  font-weight: 600;
}

.qr-back-main {
  flex-shrink: 0;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text);
  padding: 0.45rem 1rem;
  border: 1px solid var(--border);
  border-radius: 999px;
  transition: border-color var(--transition), color var(--transition);
}

.qr-back-main:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.qr-main {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 2rem min(4vw, 1.5rem) 3rem;
}

.qr-card {
  width: min(480px, 100%);
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: calc(var(--radius) + 4px);
  padding: 2rem 1.75rem;
}

.qr-badge {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
  background: var(--accent-soft);
  border: 1px solid rgba(232, 168, 124, 0.25);
  border-radius: 999px;
  padding: 0.3rem 0.85rem;
  margin-bottom: 1.25rem;
}

.qr-title {
  font-size: clamp(1.75rem, 5vw, 2.25rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 1rem;
}

.qr-lead {
  color: var(--text-muted);
  line-height: 1.75;
  margin-bottom: 1.75rem;
}

.qr-lead strong {
  color: var(--text);
  font-weight: 500;
}

.qr-content {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem 1.5rem;
  margin-bottom: 1.75rem;
}

.qr-content h2 {
  font-size: 0.95rem;
  font-weight: 600;
  margin-bottom: 0.75rem;
}

.qr-content h2:not(:first-child) {
  margin-top: 1.25rem;
}

.qr-text {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.75;
}

.qr-tags {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.qr-tags li {
  font-size: 0.8rem;
  padding: 0.35rem 0.85rem;
  background: var(--accent-soft);
  border: 1px solid rgba(232, 168, 124, 0.25);
  border-radius: 999px;
  color: var(--accent);
}

.qr-actions {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.qr-cta--secondary {
  background: var(--surface);
  border-color: var(--border);
}

.qr-cta--secondary:hover {
  background: var(--bg-elevated);
  border-color: rgba(232, 168, 124, 0.35);
}

.qr-cta--secondary .qr-cta-url {
  color: var(--text);
}

.qr-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  margin-bottom: 1rem;
}

.qr-list li {
  font-size: 0.9rem;
  color: var(--text-muted);
  padding-left: 1.1rem;
  position: relative;
}

.qr-list li::before {
  content: "·";
  position: absolute;
  left: 0;
  color: var(--accent);
  font-weight: 700;
}

.qr-note {
  font-size: 0.8rem;
  color: var(--text-muted);
  opacity: 0.8;
}

.qr-note code {
  font-family: "DM Sans", monospace, sans-serif;
  font-size: 0.85em;
  color: var(--accent);
}

.qr-cta {
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
  padding: 1rem 1.25rem;
  background: var(--accent-soft);
  border: 1px solid rgba(232, 168, 124, 0.35);
  border-radius: var(--radius);
  transition: background var(--transition), border-color var(--transition);
}

.qr-cta:hover {
  background: rgba(232, 168, 124, 0.22);
  border-color: var(--accent);
}

.qr-cta-label {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.qr-cta-url {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--accent);
}

.qr-footer {
  padding: 1.25rem;
  text-align: center;
  font-size: 0.8rem;
  color: var(--text-muted);
  border-top: 1px solid var(--border);
}

/* ── Mobile ── */
@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
  }

  .nav-links {
    position: fixed;
    top: 0;
    right: 0;
    width: min(280px, 80vw);
    height: 100vh;
    flex-direction: column;
    gap: 0;
    padding: 5rem 2rem 2rem;
    background: var(--bg-elevated);
    border-left: 1px solid var(--border);
    transform: translateX(100%);
    transition: transform var(--transition);
  }

  .nav-links.open {
    transform: translateX(0);
  }

  .nav-links li {
    border-bottom: 1px solid var(--border);
  }

  .nav-links a {
    display: block;
    padding: 1rem 0;
    font-size: 1.1rem;
  }

  .nav-toggle.open span:first-child {
    transform: rotate(45deg) translate(3px, 3px);
  }

  .nav-toggle.open span:last-child {
    transform: rotate(-45deg) translate(3px, -3px);
  }

  .about-grid {
    grid-template-columns: 1fr;
  }

  .about-tags {
    flex-direction: row;
    flex-wrap: wrap;
  }

  .footer-inner {
    flex-direction: column;
    gap: 0.75rem;
    text-align: center;
  }
}