/* Elbstrom — Hamburg Green City & Sustainability Journal */
/* site.css — v2.1, last updated 2024-11-08 */

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

:root {
  --green-dark: #1B5E20;
  --green-mid: #2E7D32;
  --green-light: #4CAF50;
  --lime: #7CB342;
  --lime-pale: #C5E1A5;
  --bg: #FAFCFA;
  --bg-card: #FFFFFF;
  --text: #212121;
  --text-secondary: #555;
  --text-light: #777;
  --border: #E0E0E0;
  --shadow: 0 2px 8px rgba(0,0,0,.07);
  --shadow-hover: 0 4px 16px rgba(0,0,0,.12);
  --radius: 8px;
  --max-width: 1120px;
  --header-h: 64px;
  --font-body: Georgia, "Times New Roman", serif;
  --font-ui: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

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

body {
  font-family: var(--font-body);
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--green-dark);
  text-decoration: none;
  transition: color .2s;
}
a:hover {
  color: var(--lime);
}

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

/* -------- HEADER / NAV -------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--green-dark);
  color: #fff;
  height: var(--header-h);
  box-shadow: 0 2px 6px rgba(0,0,0,.15);
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.site-logo {
  font-family: var(--font-ui);
  font-size: 1.35rem;
  font-weight: 700;
  color: #fff;
  letter-spacing: .02em;
  display: flex;
  align-items: center;
  gap: 8px;
}
.site-logo span.leaf {
  font-size: 1.5rem;
}
.site-logo:hover {
  color: var(--lime-pale);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 28px;
}
.site-nav a {
  font-family: var(--font-ui);
  font-size: .9rem;
  font-weight: 500;
  color: rgba(255,255,255,.85);
  letter-spacing: .03em;
  text-transform: uppercase;
  padding: 4px 0;
  border-bottom: 2px solid transparent;
  transition: color .2s, border-color .2s;
}
.site-nav a:hover,
.site-nav a.active {
  color: #fff;
  border-bottom-color: var(--lime);
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  color: #fff;
  font-size: 1.6rem;
  cursor: pointer;
  padding: 4px;
  line-height: 1;
}

/* -------- MAIN CONTENT -------- */

main {
  flex: 1;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 40px 24px;
  width: 100%;
}

/* -------- HERO BANNER (home) -------- */

.hero-banner {
  background: linear-gradient(135deg, var(--green-dark), var(--green-mid));
  color: #fff;
  border-radius: var(--radius);
  padding: 48px 40px;
  margin-bottom: 40px;
}
.hero-banner h1 {
  font-family: var(--font-ui);
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 12px;
  line-height: 1.25;
}
.hero-banner p {
  font-size: 1.05rem;
  opacity: .9;
  max-width: 600px;
  line-height: 1.6;
}

/* -------- CARD GRID -------- */

.section-label {
  font-family: var(--font-ui);
  font-size: .8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: .08em;
  color: var(--text-light);
  margin-bottom: 20px;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  margin-bottom: 48px;
}

.card {
  background: var(--bg-card);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: box-shadow .25s, transform .25s;
  display: flex;
  flex-direction: column;
}
.card:hover {
  box-shadow: var(--shadow-hover);
  transform: translateY(-3px);
}

.card-thumb {
  height: 180px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 3.5rem;
  position: relative;
}
.card-thumb .thumb-tag {
  position: absolute;
  top: 12px;
  left: 12px;
  font-family: var(--font-ui);
  font-size: .7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: .06em;
  background: rgba(255,255,255,.92);
  color: var(--green-dark);
  padding: 3px 10px;
  border-radius: 4px;
}

.card-body {
  padding: 20px;
  flex: 1;
  display: flex;
  flex-direction: column;
}
.card-body h3 {
  font-family: var(--font-ui);
  font-size: 1.05rem;
  font-weight: 700;
  line-height: 1.35;
  margin-bottom: 8px;
  color: var(--text);
}
.card-body h3 a {
  color: inherit;
}
.card-body h3 a:hover {
  color: var(--green-mid);
}
.card-body .excerpt {
  font-size: .92rem;
  color: var(--text-secondary);
  line-height: 1.55;
  flex: 1;
  margin-bottom: 14px;
}
.card-meta {
  font-family: var(--font-ui);
  font-size: .78rem;
  color: var(--text-light);
  display: flex;
  gap: 12px;
}

/* -------- ARTICLE LAYOUT -------- */

.article-header {
  margin-bottom: 36px;
  padding-bottom: 28px;
  border-bottom: 1px solid var(--border);
}
.article-header .tag {
  display: inline-block;
  font-family: var(--font-ui);
  font-size: .75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: .07em;
  color: #fff;
  background: var(--lime);
  padding: 3px 12px;
  border-radius: 4px;
  margin-bottom: 14px;
}
.article-header h1 {
  font-family: var(--font-ui);
  font-size: 2.1rem;
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 14px;
  color: var(--text);
}
.article-header .meta {
  font-family: var(--font-ui);
  font-size: .85rem;
  color: var(--text-light);
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.article-content {
  max-width: 720px;
}
.article-content p {
  margin-bottom: 1.4em;
}
.article-content h2 {
  font-family: var(--font-ui);
  font-size: 1.35rem;
  font-weight: 700;
  margin: 2em 0 .8em;
  color: var(--green-dark);
}
.article-content h3 {
  font-family: var(--font-ui);
  font-size: 1.1rem;
  font-weight: 600;
  margin: 1.6em 0 .6em;
}
.article-content ul,
.article-content ol {
  margin: 0 0 1.4em 1.6em;
}
.article-content li {
  margin-bottom: .4em;
}
.article-content blockquote {
  border-left: 4px solid var(--lime);
  margin: 1.6em 0;
  padding: 16px 24px;
  background: #F1F8E9;
  border-radius: 0 var(--radius) var(--radius) 0;
  font-style: italic;
  color: var(--text-secondary);
}
.article-content blockquote cite {
  display: block;
  margin-top: 8px;
  font-style: normal;
  font-size: .88rem;
  color: var(--text-light);
}
.article-content .article-thumb {
  width: 100%;
  height: 280px;
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 5rem;
  margin-bottom: 32px;
}

/* -------- PAGE LAYOUT (about, contact, privacy) -------- */

.page-header {
  margin-bottom: 32px;
}
.page-header h1 {
  font-family: var(--font-ui);
  font-size: 2rem;
  font-weight: 800;
  color: var(--text);
}

.page-content {
  max-width: 720px;
}
.page-content p {
  margin-bottom: 1.3em;
}
.page-content h2 {
  font-family: var(--font-ui);
  font-size: 1.3rem;
  font-weight: 700;
  margin: 1.8em 0 .7em;
  color: var(--green-dark);
}
.page-content h3 {
  font-family: var(--font-ui);
  font-size: 1.05rem;
  font-weight: 600;
  margin: 1.4em 0 .5em;
}
.page-content ul {
  margin: 0 0 1.3em 1.5em;
}
.page-content li {
  margin-bottom: .35em;
}
.page-content address {
  font-style: normal;
  background: #F1F8E9;
  padding: 20px 24px;
  border-radius: var(--radius);
  border-left: 4px solid var(--lime);
  margin: 1.2em 0;
  line-height: 1.8;
}

/* -------- FOOTER -------- */

.site-footer {
  background: var(--green-dark);
  color: rgba(255,255,255,.8);
  margin-top: auto;
  padding: 36px 24px;
}
.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 24px;
}
.footer-brand {
  font-family: var(--font-ui);
  font-size: 1.1rem;
  font-weight: 700;
  color: #fff;
  margin-bottom: 6px;
}
.footer-copy {
  font-family: var(--font-ui);
  font-size: .82rem;
  opacity: .7;
}
.footer-links {
  display: flex;
  gap: 20px;
}
.footer-links a {
  font-family: var(--font-ui);
  font-size: .85rem;
  color: rgba(255,255,255,.75);
}
.footer-links a:hover {
  color: var(--lime-pale);
}

/* -------- RESPONSIVE -------- */

@media (max-width: 900px) {
  .card-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
  }
  .hero-banner {
    padding: 36px 28px;
  }
  .hero-banner h1 {
    font-size: 1.6rem;
  }
}

@media (max-width: 640px) {
  :root {
    --header-h: 56px;
  }
  .site-nav {
    display: none;
    position: absolute;
    top: var(--header-h);
    left: 0;
    right: 0;
    background: var(--green-dark);
    flex-direction: column;
    padding: 16px 24px;
    gap: 12px;
    box-shadow: 0 4px 12px rgba(0,0,0,.2);
  }
  .site-nav.open {
    display: flex;
  }
  .nav-toggle {
    display: block;
  }
  .card-grid {
    grid-template-columns: 1fr;
    gap: 18px;
  }
  .hero-banner {
    padding: 28px 20px;
  }
  .hero-banner h1 {
    font-size: 1.35rem;
  }
  .article-header h1 {
    font-size: 1.55rem;
  }
  .footer-inner {
    flex-direction: column;
    text-align: center;
    align-items: center;
  }
  .footer-links {
    flex-wrap: wrap;
    justify-content: center;
  }
}