@import url('https://fonts.googleapis.com/css2?family=Source+Serif+4:ital,opsz,wght@0,8..60,300;0,8..60,400;0,8..60,600;0,8..60,700;1,8..60,400&family=JetBrains+Mono:wght@400;500&display=swap');

:root {
  --navy: #1B2A4A;
  --navy-light: #243557;
  --navy-dark: #121D35;
  --blue: #4A90D9;
  --blue-light: #7BA3CC;
  --teal: #5BC0BE;
  --green: #2ECC71;
  --white: #F5F5F0;
  --cream: #E8E6DF;
  --muted: #9CA3AF;
  --body-text: #D4D2CB;
  --serif: 'Source Serif 4', Georgia, serif;
  --mono: 'JetBrains Mono', monospace;
  --max-w: 720px;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--serif);
  background: var(--navy-dark);
  color: var(--body-text);
  font-size: 18px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--blue); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--teal); }

/* ── NAV ── */
nav {
  position: fixed; top: 0; width: 100%; z-index: 100;
  background: rgba(18, 29, 53, 0.92); backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(74, 144, 217, 0.1);
}
nav .nav-inner {
  max-width: 1100px; margin: 0 auto;
  display: flex; justify-content: space-between; align-items: center;
  padding: 16px 24px;
}
nav .logo { font-size: 18px; font-weight: 600; color: var(--white); letter-spacing: 0.5px; }
nav .logo span { color: var(--blue); }
nav .nav-links { display: flex; gap: 32px; font-size: 15px; }
nav .nav-links a { color: var(--muted); font-weight: 400; }
nav .nav-links a:hover { color: var(--white); }

/* ── HERO ── */
.hero {
  padding: 160px 24px 100px;
  text-align: center;
  max-width: 900px; margin: 0 auto;
}
.hero h1 {
  font-size: 48px; line-height: 1.2; font-weight: 700;
  color: var(--white); margin-bottom: 24px;
}
.hero h1 .accent { color: var(--teal); }
.hero .subtitle {
  font-size: 20px; color: var(--muted); max-width: 640px;
  margin: 0 auto 40px; line-height: 1.6;
}
.hero .formula {
  font-family: var(--mono); font-size: 24px;
  color: var(--blue); margin-bottom: 48px;
  letter-spacing: 2px;
}
.hero .cta-row { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.btn {
  display: inline-block; padding: 14px 32px; border-radius: 6px;
  font-family: var(--serif); font-size: 16px; font-weight: 600;
  transition: all 0.2s;
}
.btn-primary { background: var(--blue); color: var(--white); }
.btn-primary:hover { background: var(--teal); color: var(--navy-dark); }
.btn-outline { border: 1px solid var(--blue); color: var(--blue); }
.btn-outline:hover { background: var(--blue); color: var(--white); }

/* ── SECTION ── */
section { padding: 80px 24px; }
section.alt { background: var(--navy); }

.section-inner { max-width: var(--max-w); margin: 0 auto; }
.section-wide { max-width: 1100px; margin: 0 auto; }

h2 {
  font-size: 32px; font-weight: 700; color: var(--white);
  margin-bottom: 16px; line-height: 1.3;
}
h2 .accent { color: var(--teal); }

.section-sub {
  font-size: 18px; color: var(--muted); margin-bottom: 48px;
  max-width: 600px;
}

/* ── THREE PILLARS ── */
.pillars { display: grid; grid-template-columns: repeat(3, 1fr); gap: 32px; margin-top: 48px; }
.pillar {
  background: var(--navy-dark); border: 1px solid rgba(74, 144, 217, 0.15);
  border-radius: 8px; padding: 32px; transition: border-color 0.2s;
}
.pillar:hover { border-color: var(--blue); }
.pillar h3 { font-size: 20px; color: var(--white); margin-bottom: 12px; font-weight: 600; }
.pillar p { font-size: 16px; color: var(--muted); line-height: 1.6; }
.pillar .icon {
  font-family: var(--mono); font-size: 28px; color: var(--teal);
  margin-bottom: 16px; display: block;
}

/* ── BLOG INDEX ── */
.article-list { display: flex; flex-direction: column; gap: 24px; }
.article-card {
  display: block; padding: 28px 32px;
  background: var(--navy); border: 1px solid rgba(74, 144, 217, 0.1);
  border-radius: 8px; transition: all 0.2s;
}
.article-card:hover { border-color: var(--blue); transform: translateY(-2px); }
.article-card .meta {
  font-size: 13px; color: var(--muted); font-family: var(--mono);
  margin-bottom: 8px; text-transform: uppercase; letter-spacing: 1px;
}
.article-card h3 { font-size: 22px; color: var(--white); margin-bottom: 8px; font-weight: 600; }
.article-card p { font-size: 16px; color: var(--muted); line-height: 1.5; }
.article-card .tags { margin-top: 12px; display: flex; gap: 8px; flex-wrap: wrap; }
.tag {
  font-family: var(--mono); font-size: 12px;
  padding: 3px 10px; border-radius: 4px;
  background: rgba(74, 144, 217, 0.1); color: var(--blue-light);
}

/* ── ARTICLE PAGE ── */
.article-header { padding: 140px 24px 60px; max-width: var(--max-w); margin: 0 auto; }
.article-header .meta {
  font-family: var(--mono); font-size: 13px; color: var(--muted);
  text-transform: uppercase; letter-spacing: 1px; margin-bottom: 16px;
}
.article-header h1 {
  font-size: 40px; line-height: 1.25; font-weight: 700;
  color: var(--white); margin-bottom: 16px;
}
.article-header .subtitle-text {
  font-size: 20px; color: var(--muted); line-height: 1.5;
  font-style: italic;
}

.article-body { max-width: var(--max-w); margin: 0 auto; padding: 0 24px 80px; }
.article-body h2 {
  font-size: 26px; margin-top: 48px; margin-bottom: 16px;
  padding-top: 24px; border-top: 1px solid rgba(74, 144, 217, 0.15);
}
.article-body p { margin-bottom: 20px; }
.article-body strong { color: var(--white); font-weight: 600; }
.article-body em { color: var(--blue-light); }
.article-body blockquote {
  border-left: 3px solid var(--teal); padding: 16px 24px;
  margin: 28px 0; background: rgba(91, 192, 190, 0.05);
  font-style: italic; color: var(--cream);
}
.article-body code {
  font-family: var(--mono); font-size: 15px;
  background: var(--navy); padding: 2px 6px; border-radius: 3px;
}
.article-body pre {
  background: var(--navy); border: 1px solid rgba(74, 144, 217, 0.15);
  border-radius: 6px; padding: 20px 24px; overflow-x: auto;
  margin: 24px 0; line-height: 1.5;
}
.article-body pre code { background: none; padding: 0; font-size: 14px; }
.article-body table {
  width: 100%; border-collapse: collapse; margin: 24px 0;
  font-size: 15px;
}
.article-body th {
  text-align: left; padding: 10px 16px; border-bottom: 2px solid var(--blue);
  color: var(--white); font-weight: 600;
}
.article-body td {
  padding: 10px 16px; border-bottom: 1px solid rgba(74, 144, 217, 0.1);
}
.article-body hr {
  border: none; border-top: 1px solid rgba(74, 144, 217, 0.15);
  margin: 40px 0;
}
.article-body ul, .article-body ol { margin: 16px 0 20px 24px; }
.article-body li { margin-bottom: 8px; }

/* ── CALLOUT BOXES ── */
.callout {
  border-left: 3px solid var(--blue); padding: 20px 24px;
  margin: 28px 0; background: rgba(74, 144, 217, 0.05);
  border-radius: 0 6px 6px 0;
}
.callout.danger { border-left-color: #E74C3C; background: rgba(231, 76, 60, 0.05); }
.callout.success { border-left-color: var(--green); background: rgba(46, 204, 113, 0.05); }

/* ── NOTE FROM US ── */
.note-from-us {
  margin-top: 60px; padding: 40px 32px;
  background: var(--navy); border-radius: 8px;
  border: 1px solid rgba(74, 144, 217, 0.15);
}
.note-from-us h2 { font-size: 22px; margin-bottom: 16px; }
.note-from-us a.email {
  font-family: var(--mono); font-size: 18px;
  color: var(--teal); display: block; margin: 16px 0;
}

/* ── SERIES NAV ── */
.series-nav {
  margin-top: 48px; padding-top: 32px;
  border-top: 1px solid rgba(74, 144, 217, 0.15);
  display: flex; justify-content: space-between; gap: 24px;
}
.series-nav a {
  font-size: 15px; color: var(--muted);
  display: flex; flex-direction: column; gap: 4px;
}
.series-nav a:hover { color: var(--white); }
.series-nav .label { font-family: var(--mono); font-size: 12px; text-transform: uppercase; letter-spacing: 1px; }
.series-nav .next { text-align: right; }

/* ── FOOTER ── */
footer {
  padding: 48px 24px; text-align: center;
  border-top: 1px solid rgba(74, 144, 217, 0.1);
  font-size: 14px; color: var(--muted);
}
footer .footer-links { margin-bottom: 16px; display: flex; justify-content: center; gap: 24px; }
footer a { color: var(--muted); }
footer a:hover { color: var(--white); }
footer .tagline { font-family: var(--mono); font-size: 13px; color: rgba(74, 144, 217, 0.5); }

/* ── RESPONSIVE ── */
@media (max-width: 768px) {
  .hero h1 { font-size: 32px; }
  .hero .formula { font-size: 18px; }
  .pillars { grid-template-columns: 1fr; }
  .article-header h1 { font-size: 28px; }
  nav .nav-links { gap: 20px; font-size: 14px; }
  .series-nav { flex-direction: column; }
}