:root {
  --bg: #071018;
  --surface: rgba(255, 255, 255, 0.06);
  --surface-strong: rgba(255, 255, 255, 0.1);
  --text: #f4f8ff;
  --muted: #a9bdd3;
  --primary: #62f2c1;
  --accent: #ffb86c;
  --border: rgba(255, 255, 255, 0.12);
  --max-width: 1024px;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
  font-family: "Noto Sans TC", sans-serif;
  color: var(--text);
  background: radial-gradient(circle at 15% 20%, #12304a 0%, #071018 40%),
    linear-gradient(120deg, #08111b 0%, #0a1622 100%);
  min-height: 100%;
}

.bg-grid {
  position: fixed;
  inset: 0;
  background-image: linear-gradient(rgba(255, 255, 255, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.03) 1px, transparent 1px);
  background-size: 28px 28px;
  mask-image: radial-gradient(circle at center, black 30%, transparent 95%);
  pointer-events: none;
  z-index: 0;
}

.site-header,
main,
footer {
  position: relative;
  z-index: 1;
}

.site-header {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 22px 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-family: "Space Grotesk", sans-serif;
  text-decoration: none;
  color: var(--text);
  font-weight: 700;
  letter-spacing: 0.06em;
}

nav {
  display: flex;
  gap: 16px;
}

nav a {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.95rem;
}

nav a:hover {
  color: var(--text);
}

.language-switch {
  display: inline-flex;
  border: 1px solid var(--border);
  border-radius: 999px;
  overflow: hidden;
}

.lang-btn {
  border: 0;
  min-width: 58px;
  padding: 8px 12px;
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  font-family: "Space Grotesk", sans-serif;
  font-size: 0.8rem;
  letter-spacing: 0.06em;
  text-align: center;
}

.lang-btn.active {
  background: var(--primary);
  color: #052119;
  font-weight: 700;
}

main {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 10px 20px 80px;
  display: grid;
  gap: 20px;
}

.hero {
  padding: 52px 32px;
  border-radius: 20px;
  background: linear-gradient(145deg, rgba(98, 242, 193, 0.12), rgba(255, 184, 108, 0.12));
  border: 1px solid var(--border);
  backdrop-filter: blur(6px);
}

.tag {
  font-family: "Space Grotesk", sans-serif;
  font-size: 0.8rem;
  letter-spacing: 0.14em;
  color: var(--primary);
  margin: 0 0 10px;
}

h1,
h2,
h3 {
  margin-top: 0;
}

h1 {
  font-family: "Space Grotesk", sans-serif;
  font-size: clamp(2rem, 7vw, 3.6rem);
  line-height: 1.1;
  margin-bottom: 12px;
}

.subtitle {
  color: var(--muted);
  font-size: 1.08rem;
  max-width: 620px;
}

.highlight {
  color: var(--accent);
  font-weight: 700;
}

.markdown h1,
.markdown h2,
.markdown h3 {
  margin-bottom: 12px;
}

.markdown p {
  margin: 0 0 12px;
  line-height: 1.7;
}

.markdown p:last-child {
  margin-bottom: 0;
}

.markdown ul {
  margin: 0;
  padding-left: 20px;
}

.markdown li {
  margin-bottom: 8px;
}

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

.markdown a:hover {
  text-decoration: underline;
}

.hero .markdown p {
  color: var(--muted);
  font-size: 1.08rem;
  max-width: 760px;
}

.hero .markdown h2 {
  color: var(--accent);
  font-size: 1.1rem;
  font-weight: 700;
}

.hero-actions {
  margin-top: 24px;
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.btn {
  text-decoration: none;
  padding: 11px 16px;
  border-radius: 999px;
  border: 1px solid var(--border);
  font-weight: 500;
}

.btn.primary {
  color: #052119;
  background: var(--primary);
  border-color: transparent;
}

.btn.ghost {
  color: var(--text);
  background: transparent;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 28px;
}

.project-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(210px, 1fr));
  gap: 14px;
}

.project {
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 16px;
  background: var(--surface-strong);
}

.project p {
  color: var(--muted);
}

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

.project a:hover {
  text-decoration: underline;
}

footer {
  text-align: center;
  padding: 14px;
  color: var(--muted);
}

.reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 480ms ease, transform 480ms ease;
}

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

@media (max-width: 720px) {
  .site-header {
    flex-direction: column;
    gap: 12px;
    align-items: flex-start;
  }

  nav {
    flex-wrap: wrap;
  }

  .language-switch {
    align-self: flex-start;
  }

  .hero {
    padding: 36px 22px;
  }

  .card {
    padding: 22px;
  }
}