/* ============================================
   Triops & Prehistoric Creatures, Styles
   Mobile-first, responsive, CSS-generated visuals
   ============================================ */

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

:root {
  --color-ocean: #0b3d5c;
  --color-ocean-deep: #061f30;
  --color-ocean-light: #1a6b8a;
  --color-sand: #c9a96e;
  --color-sand-light: #e8d5a8;
  --color-amber: #d4a017;
  --color-amber-glow: #f0c040;
  --color-cream: #faf3e6;
  --color-white: #ffffff;
  --color-text: #1a1a2e;
  --color-text-light: #e0dcd0;
  --color-accent: #2ecc71;
  --color-fossil: #8b7355;
  --font-heading: 'Georgia', 'Times New Roman', serif;
  --font-body: 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
  --max-width: 1100px;
  --gutter: 1rem;
}

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

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

a {
  color: var(--color-ocean-light);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
  transition: color 0.2s;
}
a:hover, a:focus {
  color: var(--color-amber);
}

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

/* --- Skip Link (Accessibility) --- */
.skip-link {
  position: absolute;
  top: -100%;
  left: 0;
  background: var(--color-ocean);
  color: var(--color-white);
  padding: 0.5rem 1rem;
  z-index: 1000;
  font-weight: 600;
}
.skip-link:focus {
  top: 0;
}

/* --- Header & Navigation --- */
.site-header {
  background: var(--color-ocean-deep);
  color: var(--color-text-light);
  padding: 0.75rem var(--gutter);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 8px rgba(0,0,0,0.3);
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.site-logo {
  font-family: var(--font-heading);
  font-size: 1.4rem;
  color: var(--color-amber-glow);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.site-logo:hover { color: var(--color-sand-light); }

/* CSS triops icon */
.logo-icon {
  width: 28px;
  height: 28px;
  border-radius: 50% 50% 40% 40%;
  background: radial-gradient(circle at 40% 35%, var(--color-sand), var(--color-fossil));
  position: relative;
  flex-shrink: 0;
}
.logo-icon::before {
  content: '';
  position: absolute;
  width: 8px; height: 8px;
  background: var(--color-ocean-deep);
  border-radius: 50%;
  top: 7px; left: 5px;
}
.logo-icon::after {
  content: '';
  position: absolute;
  width: 8px; height: 8px;
  background: var(--color-ocean-deep);
  border-radius: 50%;
  top: 7px; right: 5px;
}

.nav-toggle {
  display: none;
  background: none;
  border: 2px solid var(--color-text-light);
  color: var(--color-text-light);
  padding: 0.3rem 0.6rem;
  border-radius: 4px;
  font-size: 1.1rem;
  cursor: pointer;
}

.main-nav ul {
  list-style: none;
  display: flex;
  gap: 1.25rem;
}
.main-nav a {
  color: var(--color-text-light);
  text-decoration: none;
  font-size: 0.95rem;
  padding: 0.25rem 0;
  border-bottom: 2px solid transparent;
  transition: border-color 0.2s, color 0.2s;
}
.main-nav a:hover,
.main-nav a[aria-current="page"] {
  color: var(--color-amber-glow);
  border-bottom-color: var(--color-amber-glow);
}

/* --- Hero Section --- */
.hero {
  background: linear-gradient(135deg, var(--color-ocean-deep) 0%, var(--color-ocean) 50%, var(--color-ocean-light) 100%);
  color: var(--color-white);
  padding: 4rem var(--gutter) 3rem;
  text-align: center;
  position: relative;
  overflow: hidden;
}

/* CSS-generated water/bubble effect */
.hero::before {
  content: '';
  position: absolute;
  width: 200px; height: 200px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(255,255,255,0.08) 0%, transparent 70%);
  top: -40px; left: 10%;
  animation: float 8s ease-in-out infinite;
}
.hero::after {
  content: '';
  position: absolute;
  width: 300px; height: 300px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(255,255,255,0.05) 0%, transparent 70%);
  bottom: -80px; right: 5%;
  animation: float 10s ease-in-out infinite reverse;
}

@keyframes float {
  0%, 100% { transform: translateY(0) scale(1); }
  50% { transform: translateY(-20px) scale(1.05); }
}

.hero h1 {
  font-family: var(--font-heading);
  font-size: clamp(2rem, 5vw, 3.2rem);
  margin-bottom: 1rem;
  position: relative;
  z-index: 1;
}
.hero p {
  font-size: clamp(1rem, 2.5vw, 1.25rem);
  max-width: 650px;
  margin: 0 auto 1.5rem;
  opacity: 0.92;
  position: relative;
  z-index: 1;
}
.hero-cta {
  display: inline-block;
  background: var(--color-amber);
  color: var(--color-ocean-deep);
  padding: 0.75rem 1.8rem;
  border-radius: 6px;
  text-decoration: none;
  font-weight: 700;
  font-size: 1.05rem;
  transition: background 0.2s, transform 0.15s;
  position: relative;
  z-index: 1;
}
.hero-cta:hover {
  background: var(--color-amber-glow);
  transform: translateY(-2px);
}

/* --- Section Styles --- */
.section {
  padding: 3rem var(--gutter);
}
.section-inner {
  max-width: var(--max-width);
  margin: 0 auto;
}
.section h2 {
  font-family: var(--font-heading);
  font-size: clamp(1.5rem, 3.5vw, 2.2rem);
  color: var(--color-ocean);
  margin-bottom: 1rem;
  border-bottom: 3px solid var(--color-sand);
  padding-bottom: 0.5rem;
}
.section h3 {
  font-family: var(--font-heading);
  font-size: 1.2rem;
  color: var(--color-ocean-light);
  margin-top: 1.5rem;
  margin-bottom: 0.5rem;
}
.section p {
  margin-bottom: 1rem;
  max-width: 80ch;
}

/* Alternating section backgrounds */
.section--alt {
  background: var(--color-white);
}
.section--ocean {
  background: linear-gradient(180deg, var(--color-ocean) 0%, var(--color-ocean-deep) 100%);
  color: var(--color-text-light);
}
.section--ocean h2 {
  color: var(--color-amber-glow);
  border-bottom-color: var(--color-ocean-light);
}
.section--ocean p { color: var(--color-text-light); }

/* --- Feature Cards (Homepage) --- */
.card-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
  margin-top: 1.5rem;
}
.card {
  background: var(--color-white);
  border-radius: 10px;
  padding: 1.5rem;
  box-shadow: 0 2px 10px rgba(0,0,0,0.08);
  transition: transform 0.2s, box-shadow 0.2s;
  border-left: 4px solid var(--color-sand);
}
.card:hover {
  transform: translateY(-3px);
  box-shadow: 0 6px 20px rgba(0,0,0,0.12);
}
.card h3 {
  font-family: var(--font-heading);
  color: var(--color-ocean);
  margin-bottom: 0.5rem;
}
.card p { font-size: 0.95rem; }
.card a.card-link {
  display: inline-block;
  margin-top: 0.75rem;
  font-weight: 600;
  font-size: 0.9rem;
}

/* --- Creature Profile Cards --- */
.creature-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
  margin-top: 2rem;
}
.creature-card {
  background: var(--color-white);
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 4px 16px rgba(0,0,0,0.1);
  transition: transform 0.2s;
}
.creature-card:hover { transform: translateY(-4px); }

.creature-visual {
  height: 180px;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
}

/* CSS-generated creature silhouettes */
.creature-visual--triops {
  background: linear-gradient(180deg, #1a6b8a 0%, #0b3d5c 100%);
}
.creature-visual--trilobite {
  background: linear-gradient(180deg, #5c4a1e 0%, #3a2e10 100%);
}
.creature-visual--ammonite {
  background: linear-gradient(180deg, #4a3060 0%, #2a1a40 100%);
}
.creature-visual--anomalocaris {
  background: linear-gradient(180deg, #2a5a3a 0%, #1a3a2a 100%);
}
.creature-visual--eurypterus {
  background: linear-gradient(180deg, #5a3a2a 0%, #3a2218 100%);
}
.creature-visual--hallucigenia {
  background: linear-gradient(180deg, #4a3a5a 0%, #2a2040 100%);
}
.creature-visual--opabinia {
  background: linear-gradient(180deg, #3a5a5a 0%, #1a3a3a 100%);
}

.creature-visual .silhouette {
  width: 100px;
  height: 80px;
  background: rgba(255,255,255,0.15);
  border-radius: 50%;
}

.creature-card .card-body {
  padding: 1.25rem;
}
.creature-card h3 {
  font-family: var(--font-heading);
  font-size: 1.15rem;
  color: var(--color-ocean);
  margin-bottom: 0.25rem;
}
.creature-card .taxonomy {
  font-size: 0.8rem;
  color: var(--color-fossil);
  font-style: italic;
  margin-bottom: 0.5rem;
}
.creature-card p {
  font-size: 0.9rem;
  line-height: 1.5;
}
.creature-card .era-badge {
  display: inline-block;
  background: var(--color-sand-light);
  color: var(--color-ocean-deep);
  padding: 0.2rem 0.6rem;
  border-radius: 20px;
  font-size: 0.75rem;
  font-weight: 600;
  margin-top: 0.5rem;
}

/* --- Deep Dive Content --- */
.content-block {
  margin-bottom: 2rem;
}
.content-block h3 {
  font-size: 1.3rem;
  color: var(--color-ocean);
  margin-bottom: 0.75rem;
}

.info-table {
  width: 100%;
  border-collapse: collapse;
  margin: 1rem 0;
  font-size: 0.9rem;
}
.info-table th,
.info-table td {
  padding: 0.6rem 0.8rem;
  text-align: left;
  border-bottom: 1px solid #e0dcd0;
}
.info-table th {
  background: var(--color-ocean);
  color: var(--color-white);
  font-weight: 600;
}
.info-table tr:nth-child(even) {
  background: rgba(0,0,0,0.03);
}

/* --- Timeline --- */
.timeline {
  position: relative;
  padding-left: 2rem;
  margin: 1.5rem 0;
}
.timeline::before {
  content: '';
  position: absolute;
  left: 0.5rem;
  top: 0;
  bottom: 0;
  width: 3px;
  background: var(--color-sand);
  border-radius: 3px;
}
.timeline-item {
  position: relative;
  margin-bottom: 1.5rem;
  padding-left: 1rem;
}
.timeline-item::before {
  content: '';
  position: absolute;
  left: -1.65rem;
  top: 0.3rem;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--color-ocean-light);
  border: 3px solid var(--color-sand);
}
.timeline-item .era {
  font-weight: 700;
  color: var(--color-ocean);
  font-size: 0.95rem;
}
.timeline-item .desc {
  font-size: 0.9rem;
  color: #555;
}

/* --- Pet Care Section --- */
.care-steps {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.25rem;
  margin-top: 1.5rem;
}
.care-step {
  background: var(--color-white);
  border-radius: 8px;
  padding: 1.25rem;
  box-shadow: 0 2px 8px rgba(0,0,0,0.06);
  border-left: 4px solid var(--color-accent);
}
.care-step h4 {
  color: var(--color-ocean);
  margin-bottom: 0.4rem;
}

/* --- About Page --- */
.team-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
  margin-top: 1.5rem;
}
.team-card {
  background: var(--color-white);
  border-radius: 10px;
  padding: 1.5rem;
  text-align: center;
  box-shadow: 0 2px 10px rgba(0,0,0,0.08);
}
.avatar-placeholder {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  margin: 0 auto 1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2rem;
  font-family: var(--font-heading);
  color: var(--color-white);
}
.avatar-placeholder--1 { background: var(--color-ocean-light); }
.avatar-placeholder--2 { background: var(--color-sand); }
.avatar-placeholder--3 { background: var(--color-fossil); }

/* --- Footer --- */
.site-footer {
  background: var(--color-ocean-deep);
  color: var(--color-text-light);
  padding: 2rem var(--gutter);
  margin-top: auto;
}
.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
  justify-content: space-between;
  align-items: start;
}
.footer-col h4 {
  color: var(--color-amber-glow);
  margin-bottom: 0.5rem;
  font-size: 0.95rem;
}
.footer-col ul {
  list-style: none;
}
.footer-col a {
  color: var(--color-text-light);
  text-decoration: none;
  font-size: 0.88rem;
}
.footer-col a:hover { color: var(--color-amber-glow); }
.footer-bottom {
  max-width: var(--max-width);
  margin: 1.5rem auto 0;
  padding-top: 1rem;
  border-top: 1px solid rgba(255,255,255,0.15);
  text-align: center;
  font-size: 0.8rem;
  opacity: 0.7;
}

/* --- Responsive Breakpoints --- */
@media (min-width: 600px) {
  .card-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .creature-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .care-steps {
    grid-template-columns: repeat(2, 1fr);
  }
  .team-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (min-width: 900px) {
  :root { --gutter: 2rem; }
  .hero {
    padding: 6rem var(--gutter) 4rem;
  }
  .creature-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (max-width: 640px) {
  .nav-toggle { display: block; }
  .main-nav {
    display: none;
    width: 100%;
  }
  .main-nav.open {
    display: block;
  }
  .main-nav ul {
    flex-direction: column;
    gap: 0.5rem;
    padding: 0.5rem 0;
  }
  .main-nav a {
    display: block;
    padding: 0.5rem 0;
    font-size: 1.05rem;
  }
}

/* --- Print --- */
@media print {
  .site-header, .site-footer, .nav-toggle { display: none; }
  .hero { background: #eee; color: #000; padding: 2rem; }
  .card, .creature-card { box-shadow: none; border: 1px solid #ccc; }
}