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

:root {
  --color-bg: #faf9f6;
  --color-text: #1a1a1a;
  --color-primary: #2a7a62;
  --color-primary-light: #e8f5f0;
  --color-gray: #6b7280;
  --color-border: #d1d5db;
  --font-sans: system-ui, -apple-system, sans-serif;
  --max-width: 48rem;
}

html {
  font-size: 100%;
}

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

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

a:hover {
  text-decoration: underline;
}

/* ── Header ── */
.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.5rem;
  border-bottom: 1px solid var(--color-border);
  background: #fff;
}

.logo {
  font-weight: 700;
  font-size: 1.125rem;
  color: var(--color-text);
}

.nav {
  display: flex;
  gap: 1.25rem;
}

.nav a {
  font-size: 0.9375rem;
}

/* ── Main content ── */
.content {
  flex: 1;
  max-width: var(--max-width);
  width: 100%;
  margin: 0 auto;
  padding: 2rem 1.5rem;
}

/* ── Hero ── */
.hero {
  text-align: center;
  padding: 3rem 0;
}

.hero h1 {
  font-size: 2rem;
  margin-bottom: 0.75rem;
}

.hero p {
  color: var(--color-gray);
  margin-bottom: 1.5rem;
}

.btn {
  display: inline-block;
  padding: 0.625rem 1.25rem;
  background: var(--color-primary);
  color: #fff;
  border-radius: 6px;
  font-weight: 600;
}

.btn:hover {
  opacity: 0.9;
  text-decoration: none;
}

/* ── Project grid ── */
.project-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1.5rem;
  margin: 1.5rem 0;
}

.project-card {
  background: #fff;
  border: 1px solid var(--color-border);
  border-radius: 8px;
  padding: 1.25rem;
}

.project-card h3 {
  margin-bottom: 0.5rem;
}

.project-card p {
  color: var(--color-gray);
  font-size: 0.9375rem;
  margin-bottom: 0.75rem;
}

.tag {
  display: inline-block;
  font-size: 0.8125rem;
  background: var(--color-primary-light);
  color: var(--color-primary);
  padding: 0.2rem 0.5rem;
  border-radius: 4px;
}

/* ── Project detail ── */
.project-detail header {
  margin-bottom: 1.5rem;
}

.project-meta {
  display: flex;
  gap: 1rem;
  font-size: 0.875rem;
  color: var(--color-gray);
  flex-wrap: wrap;
}

.back-link {
  display: inline-block;
  margin-top: 2rem;
}

/* ── Footer ── */
.site-footer {
  text-align: center;
  padding: 1.5rem;
  font-size: 0.875rem;
  color: var(--color-gray);
  border-top: 1px solid var(--color-border);
}