/* AquariumLab.co — style.css */
/* Design: Deep ocean blues, clean white text, authoritative "lab" feel */

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

:root {
  --deep-blue:    #020c1b;
  --blue-mid:     #0a1929;
  --blue-light:   #112240;
  --ice:          #e6f1ff;
  --frost:        #a8c7fa;
  --white:        #ffffff;
  --muted:        #8892b0;
  --accent:       #00d4aa;
  --accent-hov:   #00b892;
  --accent-warm:  #ff7043;
  --text:         #ccd6f6;
  --border:       rgba(255,255,255,0.08);
  --font:         -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
}

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  background: var(--deep-blue);
  color: var(--text);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ── Nav ── */
nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(2, 12, 27, 0.95);
  backdrop-filter: blur(6px);
  border-bottom: 1px solid var(--border);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 24px;
  max-width: 1100px;
  margin: 0 auto;
}

.nav-logo {
  font-size: 1.2rem;
  font-weight: 800;
  letter-spacing: 0.02em;
  color: var(--white);
  text-decoration: none;
}

.nav-logo span { color: var(--accent); }

.nav-links {
  display: flex;
  gap: 32px;
  list-style: none;
}

.nav-links a {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.9rem;
  transition: color 0.2s;
}

.nav-links a:hover { color: var(--white); }

/* ── Hero ── */
.hero {
  padding: 100px 0 80px;
  text-align: center;
  background: linear-gradient(180deg, var(--deep-blue) 0%, var(--blue-mid) 100%);
}

.hero-eyebrow {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 20px;
}

.hero h1 {
  font-size: clamp(2.2rem, 5vw, 3.6rem);
  font-weight: 800;
  line-height: 1.15;
  color: var(--white);
  max-width: 800px;
  margin: 0 auto 24px;
  letter-spacing: -0.02em;
}

.hero h1 em {
  font-style: normal;
  color: var(--accent);
}

.hero-sub {
  font-size: 1.1rem;
  color: var(--muted);
  max-width: 600px;
  margin: 0 auto 40px;
}

.btn-primary {
  display: inline-block;
  background: var(--accent);
  color: var(--white);
  text-decoration: none;
  font-weight: 600;
  font-size: 0.95rem;
  padding: 14px 32px;
  border-radius: 6px;
  transition: background 0.2s, transform 0.1s;
}

.btn-primary:hover {
  background: var(--accent-hov);
  transform: translateY(-1px);
}

.btn-secondary {
  display: inline-block;
  border: 1px solid var(--accent);
  color: var(--accent);
  text-decoration: none;
  font-weight: 600;
  font-size: 0.95rem;
  padding: 14px 32px;
  border-radius: 6px;
  margin-left: 12px;
  transition: all 0.2s;
}

.btn-secondary:hover {
  background: var(--accent);
  color: var(--white);
}

/* ── Section base ── */
section { padding: 80px 0; }

.section-label {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 12px;
}

.section-title {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  font-weight: 800;
  color: var(--white);
  letter-spacing: -0.02em;
  margin-bottom: 16px;
}

.section-sub {
  font-size: 1rem;
  color: var(--muted);
  max-width: 560px;
  margin-bottom: 48px;
}

/* ── Featured Guides ── */
.guides {
  background: var(--blue-mid);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.guides-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
}

.guide-card {
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 28px;
  background: var(--blue-light);
  text-decoration: none;
  display: block;
  transition: border-color 0.2s, transform 0.15s;
}

.guide-card:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
}

.guide-tag {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 10px;
}

.guide-card h3 {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--white);
  margin-bottom: 8px;
}

.guide-card p {
  font-size: 0.88rem;
  color: var(--muted);
  line-height: 1.6;
}

/* ── About ── */
.about { background: var(--deep-blue); }

.about-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}

.about-text p {
  font-size: 0.95rem;
  color: var(--muted);
  margin-bottom: 16px;
  line-height: 1.7;
}

.about-stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.stat-box {
  background: var(--blue-mid);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 20px;
  text-align: center;
}

.stat-box .number {
  font-size: 1.8rem;
  font-weight: 800;
  color: var(--accent);
  display: block;
}

.stat-box .label {
  font-size: 0.78rem;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

/* ── Newsletter CTA ── */
.newsletter {
  background: var(--blue-mid);
  text-align: center;
  border-top: 1px solid var(--border);
}

.newsletter h2 {
  font-size: clamp(1.6rem, 3vw, 2.4rem);
  font-weight: 800;
  color: var(--white);
  margin-bottom: 16px;
}

.newsletter p {
  font-size: 1rem;
  color: var(--muted);
  max-width: 480px;
  margin: 0 auto 32px;
}

.email-form {
  display: flex;
  gap: 12px;
  max-width: 460px;
  margin: 0 auto;
}

.email-form input {
  flex: 1;
  padding: 14px 18px;
  border-radius: 6px;
  border: 1px solid var(--border);
  background: var(--deep-blue);
  color: var(--white);
  font-size: 0.95rem;
}

.email-form input::placeholder { color: var(--muted); }

.email-form button {
  background: var(--accent);
  color: var(--white);
  border: none;
  padding: 14px 24px;
  border-radius: 6px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.2s;
}

.email-form button:hover { background: var(--accent-hov); }

/* ── Footer ── */
footer {
  background: var(--deep-blue);
  border-top: 1px solid var(--border);
  padding: 36px 0;
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
}

.footer-logo {
  font-weight: 700;
  font-size: 0.9rem;
  color: var(--muted);
}

.footer-logo span { color: var(--accent); }

.footer-copy {
  font-size: 0.82rem;
  color: var(--muted);
}

.footer-links {
  display: flex;
  gap: 20px;
  list-style: none;
}

.footer-links a {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.82rem;
  transition: color 0.2s;
}

.footer-links a:hover { color: var(--accent); }

/* ── Article pages ── */
.article-header {
  padding: 80px 0 40px;
  text-align: center;
  background: linear-gradient(180deg, var(--deep-blue) 0%, var(--blue-mid) 100%);
}

.article-header h1 {
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  font-weight: 800;
  color: var(--white);
  max-width: 800px;
  margin: 0 auto 16px;
}

.article-meta {
  font-size: 0.85rem;
  color: var(--muted);
}

.article-body {
  max-width: 760px;
  margin: 0 auto;
  padding: 48px 24px 80px;
}

.article-body h2 {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--white);
  margin: 40px 0 16px;
}

.article-body h3 {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--frost);
  margin: 32px 0 12px;
}

.article-body p {
  font-size: 1rem;
  color: var(--text);
  margin-bottom: 16px;
  line-height: 1.75;
}

.article-body ul, .article-body ol {
  margin: 0 0 20px 24px;
  color: var(--text);
}

.article-body li {
  margin-bottom: 8px;
  line-height: 1.65;
}

.product-box {
  background: var(--blue-light);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 24px;
  margin: 24px 0;
}

.product-box h4 {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--white);
  margin-bottom: 8px;
}

.product-box p {
  font-size: 0.9rem;
  color: var(--muted);
}

.product-box .price {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--accent);
  margin-top: 8px;
}

.affiliate-btn {
  display: inline-block;
  background: var(--accent);
  color: var(--white);
  text-decoration: none;
  font-weight: 600;
  font-size: 0.9rem;
  padding: 10px 20px;
  border-radius: 6px;
  margin-top: 12px;
  transition: background 0.2s;
}

.affiliate-btn:hover { background: var(--accent-hov); }

/* ── Mobile ── */
@media (max-width: 640px) {
  .nav-links { display: none; }
  .hero { padding: 60px 0 56px; }
  section { padding: 60px 0; }
  .about-content { grid-template-columns: 1fr; }
  .email-form { flex-direction: column; }
  .footer-inner { flex-direction: column; text-align: center; }
}