:root {
  --primary-color: #2563eb;
  --primary-hover: #1d4ed8;
  --text-color: #1f2937;
  --text-muted: #6b7280;
  --bg-color: #f9fafb;
  --nav-bg: #ffffff;
  --card-bg: #ffffff;
  --border-color: #e5e7eb;
  --ticker-bg: #334155;
  --ticker-text: #e2e8f0;
  --radius-md: 0.5rem;
  --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.06);
  --shadow-md: 0 10px 15px -3px rgba(15, 23, 42, 0.1);
  --font-main: system-ui, -apple-system, sans-serif;
  --page-width: 42rem;
  --projects-width: 68.75rem;
}

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-main);
  color: var(--text-color);
  background-color: var(--bg-color);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

header {
  background-color: var(--nav-bg);
  border-bottom: 1px solid var(--border-color);
  text-align: center;
}

header nav,
header h1,
header > p {
  padding-left: 1.5rem;
  padding-right: 1.5rem;
}

header nav {
  padding-top: 0.75rem;
  padding-bottom: 0.75rem;
}

header h1 {
  padding-top: 0.25rem;
  padding-bottom: 0.5rem;
  font-size: 1.75rem;
  font-weight: 650;
  letter-spacing: -0.02em;
  line-height: 1.25;
}

header > p {
  padding-bottom: 1.25rem;
  color: var(--text-muted);
  font-size: 0.95rem;
}

nav ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 0.35rem;
}

nav a {
  text-decoration: none;
  color: var(--text-color);
  font-weight: 500;
  font-size: 0.875rem;
  letter-spacing: 0.01em;
  padding: 0.4rem 0.85rem;
  border-radius: 0.375rem;
  transition: color 0.2s ease, background-color 0.2s ease;
}

nav a:hover,
nav a:focus-visible {
  color: var(--primary-color);
  background-color: #f3f4f6;
  outline: none;
}

nav a.active {
  color: var(--primary-color);
  background-color: #eff6ff;
}

.page {
  width: 100%;
  max-width: var(--page-width);
  margin: 0 auto;
  padding: 2rem 1.5rem 1rem;
}

.page h1 {
  font-size: 1.75rem;
  font-weight: 650;
  letter-spacing: -0.02em;
  line-height: 1.25;
  margin-bottom: 1.5rem;
  text-align: center;
}

.page h2 {
  font-size: 1.05rem;
  font-weight: 650;
  margin: 1.75rem 0 0.5rem;
}

.page p {
  color: var(--text-color);
  margin-bottom: 0.75rem;
}

.page ul {
  padding-left: 1.15rem;
  color: var(--text-color);
}

.page li {
  margin-bottom: 0.4rem;
}

.page a {
  color: var(--primary-color);
  text-decoration: none;
  font-weight: 500;
}

.page a:hover {
  text-decoration: underline;
  color: var(--primary-hover);
}

.hero {
  text-align: center;
}

.portrait {
  display: block;
  width: 10rem;
  height: 10rem;
  margin: 0 auto;
  object-fit: cover;
  border-radius: 50%;
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-sm);
}

.projects-container {
  width: 100%;
  max-width: var(--projects-width);
  margin: 0 auto;
  padding: 2rem 1.5rem 1rem;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
}

.project-card {
  background-color: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 0.75rem;
  box-shadow: var(--shadow-sm);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.project-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.project-card h2 {
  font-size: 1.15rem;
  font-weight: 650;
  margin-bottom: 0;
}

.project-card p {
  color: var(--text-muted);
  font-size: 0.95rem;
  flex-grow: 1;
}

.tags,
.project-card > div {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.tag {
  background-color: #f1f5f9;
  color: #475569;
  font-size: 0.75rem;
  font-weight: 600;
  padding: 0.25rem 0.5rem;
  border-radius: 0.25rem;
}

.project-card a {
  color: var(--primary-color);
  text-decoration: none;
  font-weight: 600;
  font-size: 0.9rem;
  margin-top: 0.25rem;
}

.project-card a:hover {
  text-decoration: underline;
  color: var(--primary-hover);
}

.ticker-wrap {
  width: 100%;
  overflow: hidden;
  background-color: var(--ticker-bg);
  color: var(--ticker-text);
  padding: 0.45rem 0;
  font-size: 0.8rem;
  font-weight: 500;
  letter-spacing: 0.01em;
}

.ticker-text {
  display: inline-block;
  white-space: nowrap;
  padding-left: 100%;
  animation: ticker 28s linear infinite;
}

@keyframes ticker {
  0% {
    transform: translate3d(0, 0, 0);
  }
  100% {
    transform: translate3d(-100%, 0, 0);
  }
}

.social-links {
  width: 100%;
  max-width: var(--page-width);
  margin: 2.5rem auto 0;
  padding: 1.5rem 1.5rem 0.5rem;
  text-align: center;
}

.social-links h2 {
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 0.75rem;
}

.social-links ul {
  list-style: none;
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 0.75rem;
}

.social-links a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.5rem;
  height: 2.5rem;
  border-radius: 50%;
  border: 1px solid var(--border-color);
  background-color: var(--card-bg);
  transition: border-color 0.2s ease, background-color 0.2s ease;
}

.social-links a:hover,
.social-links a:focus-visible {
  border-color: var(--primary-color);
  background-color: #eff6ff;
  outline: none;
}

.social-links img {
  display: block;
}

footer {
  padding: 1.25rem 1.5rem 2rem;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.8rem;
}

@media (min-width: 48rem) {
  header nav ul {
    flex-direction: row;
    gap: 0.5rem;
  }

  header h1 {
    font-size: 2rem;
  }

  .page h1 {
    font-size: 2rem;
  }
}