/* === Web fonts === */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=Noto+Sans+TC:wght@400;500;600;700&display=swap');

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

:root {
  --color-primary: #1b5e3b;
  --color-primary-light: #2a7d50;
  --color-primary-dark: #14472d;
  --color-accent: #c4953a;
  --color-accent-light: #d4a94e;
  --color-text: #2d2d2d;
  --color-text-light: #5a5a5a;
  --color-bg: #ffffff;
  --color-bg-alt: #f3f7f4;
  --color-border: #d4e0d8;
  --color-hero-bg: #0e3321;
  --font-body: "Inter", "Noto Sans TC", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-heading: "Inter", "Noto Sans TC", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --max-width: 1120px;
}

html { font-size: 16px; scroll-behavior: smooth; }

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

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
}

a { color: var(--color-primary-light); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--color-accent); }

h1, h2, h3, h4 {
  font-family: var(--font-heading);
  color: var(--color-primary);
  line-height: 1.3;
  font-weight: 700;
}

h1 { font-size: 2rem; margin-bottom: 0.75rem; }
h2 { font-size: 1.5rem; margin-top: 2rem; margin-bottom: 0.75rem; }
h3 { font-size: 1.2rem; margin-top: 1.5rem; margin-bottom: 0.5rem; }

p { margin-bottom: 1rem; }
ul, ol { margin-bottom: 1rem; padding-left: 1.5rem; }
li { margin-bottom: 0.35rem; }

/* === Header === */
.site-header {
  background: var(--color-primary);
  color: #fff;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 8px rgba(0,0,0,0.15);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.site-logo {
  color: #fff;
  display: flex;
  flex-direction: column;
  gap: 0;
  line-height: 1.2;
}
.site-logo:hover { color: var(--color-accent-light); }
.site-title { font-family: var(--font-heading); font-size: 1.15rem; font-weight: 700; letter-spacing: -0.01em; }
.site-subtitle { font-size: 0.75rem; opacity: 0.7; }

.nav-list {
  display: flex;
  list-style: none;
  gap: 0.25rem;
  align-items: center;
}

.nav-list a {
  color: rgba(255,255,255,0.85);
  padding: 0.5rem 0.85rem;
  border-radius: 4px;
  font-size: 0.95rem;
  font-weight: 500;
  transition: background 0.2s, color 0.2s;
}
.nav-list a:hover, .nav-list a.active {
  background: rgba(255,255,255,0.12);
  color: #fff;
}

.lang-switch a {
  border: 1px solid rgba(255,255,255,0.35);
  font-size: 0.85rem;
  padding: 0.35rem 0.75rem;
}
.lang-switch a:hover {
  border-color: var(--color-accent-light);
  color: var(--color-accent-light);
  background: transparent;
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  flex-direction: column;
  gap: 5px;
}
.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: #fff;
  transition: transform 0.3s, opacity 0.3s;
}
.nav-toggle.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* === Hero === */
.hero {
  background: var(--color-hero-bg);
  color: #fff;
  padding: 5.5rem 0 5rem;
  text-align: center;
  position: relative;
  overflow: hidden;
  background-image:
    radial-gradient(ellipse at 20% 80%, rgba(42,125,80,0.25) 0%, transparent 60%),
    radial-gradient(ellipse at 80% 20%, rgba(42,125,80,0.2) 0%, transparent 50%),
    linear-gradient(160deg, #0a2a18 0%, var(--color-hero-bg) 40%, #14472d 100%);
}
/* Decorative circle ornament - left side */
.hero::before {
  content: "";
  position: absolute;
  left: -100px;
  bottom: -80px;
  width: 300px;
  height: 300px;
  border: 1px solid rgba(255,255,255,0.05);
  border-radius: 50%;
  pointer-events: none;
}
/* Decorative circle ornament - right side */
.hero::after {
  content: "";
  position: absolute;
  right: -80px;
  top: -60px;
  width: 350px;
  height: 350px;
  border: 1px solid rgba(255,255,255,0.06);
  border-radius: 50%;
  pointer-events: none;
}
.hero h1 {
  color: #fff;
  font-size: 2.75rem;
  margin-bottom: 0.25rem;
  position: relative;
}
.hero-subtitle {
  font-size: 1.35rem;
  opacity: 0.7;
  margin-bottom: 1rem;
  font-weight: 500;
  position: relative;
}
.hero-desc {
  font-size: 1.1rem;
  opacity: 0.85;
  max-width: 600px;
  margin: 0 auto 2rem;
  position: relative;
}

.btn {
  display: inline-block;
  background: var(--color-accent);
  color: #fff;
  padding: 0.75rem 2rem;
  border-radius: 4px;
  font-weight: 600;
  font-size: 1rem;
  transition: background 0.2s, transform 0.2s;
  position: relative;
}
.btn:hover {
  background: var(--color-accent-light);
  color: #fff;
  transform: translateY(-1px);
}

/* === Page Header === */
.page-header {
  background: var(--color-bg-alt);
  padding: 3rem 0 2.5rem;
  border-bottom: 1px solid var(--color-border);
  position: relative;
  overflow: hidden;
}
.page-header::after {
  content: "";
  position: absolute;
  right: -30px;
  top: -20px;
  width: 220px;
  height: 280px;
  width: 200px;
  height: 200px;
  border: 1px solid rgba(27,94,59,0.06);
  border-radius: 50%;
  pointer-events: none;
}
.page-header h1 { margin-bottom: 0.5rem; position: relative; }
.lead {
  font-size: 1.1rem;
  color: var(--color-text-light);
  max-width: 720px;
  position: relative;
}

.breadcrumb {
  font-size: 0.85rem;
  margin-bottom: 0.75rem;
  color: var(--color-text-light);
  position: relative;
}
.breadcrumb a { color: var(--color-text-light); }
.breadcrumb a:hover { color: var(--color-accent); }

/* === Topic Date === */
.topic-date {
  font-size: 0.85rem;
  color: var(--color-text-light);
  margin-top: 0.5rem;
  position: relative;
}
.topic-date strong { color: var(--color-primary); font-weight: 600; }

/* === Content Sections === */
.content-section {
  padding: 3rem 0;
}

.home-about {
  max-width: 800px;
  margin: 0 auto;
  text-align: center;
}
.home-about .container { max-width: 800px; }

.home-topics {
  background: var(--color-bg-alt);
  position: relative;
  overflow: hidden;
}
.home-topics::before {
  content: "";
  position: absolute;
  top: 50%;
  left: -100px;
  width: 250px;
  height: 250px;
  border: 1px solid rgba(27,94,59,0.05);
  border-radius: 50%;
  transform: translateY(-50%);
  pointer-events: none;
}
.home-topics::after {
  content: "";
  position: absolute;
  bottom: -60px;
  right: -40px;
  width: 180px;
  height: 180px;
  border: 1px solid rgba(27,94,59,0.05);
  border-radius: 50%;
  pointer-events: none;
}
.home-topics h2 {
  text-align: center;
  margin-bottom: 2rem;
  font-size: 1.75rem;
  position: relative;
}

/* === Card Grid === */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.5rem;
  position: relative;
}

.card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 6px;
  overflow: hidden;
  transition: box-shadow 0.2s, transform 0.2s;
  border-top: 3px solid transparent;
}
.card:hover {
  box-shadow: 0 4px 16px rgba(0,0,0,0.08);
  transform: translateY(-2px);
  border-top-color: var(--color-primary-light);
}

.card a {
  display: block;
  padding: 1.75rem;
  color: var(--color-text);
  height: 100%;
}
.card a:hover { color: var(--color-text); }

.card-icon {
  font-size: 2rem;
  display: block;
  margin-bottom: 0.75rem;
}

.card h2, .card h3 {
  font-size: 1.15rem;
  margin: 0 0 0.5rem;
  color: var(--color-primary);
}
.card p {
  font-size: 0.92rem;
  color: var(--color-text-light);
  margin-bottom: 0.75rem;
}

.card-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-bottom: 0.75rem;
}
.tag {
  font-size: 0.75rem;
  background: var(--color-bg-alt);
  color: var(--color-text-light);
  padding: 0.2rem 0.5rem;
  border-radius: 3px;
  border: 1px solid var(--color-border);
}

.read-more {
  font-size: 0.9rem;
  color: var(--color-accent);
  font-weight: 600;
}

/* === Topic Page === */
.topic-layout {
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: 3rem;
  padding: 2.5rem 0 4rem;
}

.topic-sidebar {
  position: sticky;
  top: 80px;
  align-self: start;
}

.sidebar-block {
  margin-bottom: 2rem;
  padding: 1.25rem;
  background: var(--color-bg-alt);
  border-radius: 6px;
  border: 1px solid var(--color-border);
}
.sidebar-block h3 {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--color-text-light);
  margin: 0 0 0.75rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--color-border);
  font-weight: 600;
}
.sidebar-block ul { list-style: none; padding: 0; margin: 0; }
.sidebar-block li {
  font-size: 0.85rem;
  padding: 0.3rem 0;
  color: var(--color-text-light);
  border-bottom: 1px solid rgba(0,0,0,0.04);
}
.sidebar-block li:last-child { border-bottom: none; }

.lang-link {
  display: block;
  text-align: center;
  padding: 0.5rem;
  border: 1px solid var(--color-primary-light);
  border-radius: 4px;
  font-size: 0.9rem;
  color: var(--color-primary-light);
}
.lang-link:hover {
  background: var(--color-primary-light);
  color: #fff;
}

.topic-content h2 {
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--color-bg-alt);
}

.topic-content h3 {
  color: var(--color-primary-light);
}

.topic-content blockquote {
  border-left: 3px solid var(--color-primary-light);
  padding: 0.75rem 1.25rem;
  margin: 1.5rem 0;
  background: var(--color-bg-alt);
  border-radius: 0 4px 4px 0;
  color: var(--color-text-light);
  font-style: italic;
}

/* === UN Treaty Body Box === */
.un-observations {
  background: var(--color-bg-alt);
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--color-primary);
  border-radius: 0 6px 6px 0;
  padding: 1.5rem 1.75rem;
  margin: 2rem 0;
}
.un-observations h3 {
  color: var(--color-primary);
  font-size: 1.05rem;
  margin: 0 0 0.75rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.un-observations h3::before {
  content: "\1F310";
  font-size: 1.1rem;
}
.un-observations p { font-size: 0.95rem; }
.un-observations ul { font-size: 0.95rem; }

/* === Reports === */
.reports-list { max-width: 800px; }
.report-item {
  padding: 1.5rem 0;
  border-bottom: 1px solid var(--color-border);
}
.report-item:first-child { padding-top: 0; }
.report-item h2 { font-size: 1.2rem; margin: 0 0 0.5rem; }
.report-meta {
  display: inline-block;
  font-size: 0.85rem;
  color: var(--color-text-light);
  background: var(--color-bg-alt);
  padding: 0.15rem 0.6rem;
  border-radius: 3px;
  margin-right: 0.5rem;
  margin-bottom: 0.5rem;
}

.btn-download {
  display: inline-block;
  margin-top: 1.5rem;
  background: var(--color-primary);
  color: #fff;
  padding: 0.7rem 1.5rem;
  border-radius: 4px;
  font-weight: 600;
  font-size: 0.95rem;
  transition: background 0.2s;
}
.btn-download:hover { background: var(--color-primary-light); color: #fff; }

.btn-download-sm {
  display: inline-block;
  margin-top: 0.5rem;
  color: var(--color-primary);
  font-weight: 600;
  font-size: 0.9rem;
  border: 1px solid var(--color-primary);
  padding: 0.35rem 1rem;
  border-radius: 4px;
  transition: background 0.2s, color 0.2s;
}
.btn-download-sm:hover { background: var(--color-primary); color: #fff; }

/* === Single Page (About etc.) === */
.single-page .content-body {
  max-width: 800px;
  padding: 2.5rem 0 4rem;
}

/* === Footer === */
.site-footer {
  background: var(--color-primary-dark);
  color: rgba(255,255,255,0.8);
  padding: 2.5rem 0;
  font-size: 0.9rem;
  position: relative;
  overflow: hidden;
}
.site-footer::before {
  content: "";
  position: absolute;
  top: -50px;
  right: -50px;
  width: 200px;
  height: 200px;
  border: 1px solid rgba(255,255,255,0.03);
  border-radius: 50%;
  pointer-events: none;
}
.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  position: relative;
}
.footer-title {
  font-size: 1rem;
  color: #fff;
  margin-bottom: 0.35rem;
  font-weight: 600;
}
.footer-info p { margin-bottom: 0.25rem; }
.footer-info a { color: var(--color-accent-light); }
.footer-info a:hover { color: #fff; }
.footer-copy { text-align: right; opacity: 0.6; font-size: 0.85rem; }

/* === Responsive === */
@media (max-width: 768px) {
  .hero { padding: 3.5rem 0 3rem; }
  .hero h1 { font-size: 2rem; }
  .hero-subtitle { font-size: 1.1rem; }

  .nav-toggle { display: flex; }
  .nav-list {
    display: none;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: var(--color-primary);
    flex-direction: column;
    padding: 1rem;
    box-shadow: 0 4px 12px rgba(0,0,0,0.2);
  }
  .nav-list.open { display: flex; }
  .nav-list a { display: block; padding: 0.75rem 1rem; }

  .topic-layout {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
  .topic-sidebar {
    position: static;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
  }

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

  .footer-inner { flex-direction: column; align-items: flex-start; gap: 1rem; }
  .footer-copy { text-align: left; }
}