/* ── RESET & BASE ── */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 72px;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  font-size: 15px;
  line-height: 1.7;
  color: #1a1a1a;
  background: #fafafa;
}

/* ── NAV ── */
nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid #e5e5e5;
}

.nav-inner {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 1.5rem;
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-brand {
  font-weight: 700;
  font-size: 1rem;
  color: #1a1a1a;
  text-decoration: none;
  letter-spacing: -0.01em;
}

.nav-links {
  display: flex;
  gap: 1.5rem;
  list-style: none;
}

.nav-links a {
  color: #666;
  text-decoration: none;
  font-size: 0.82rem;
  font-weight: 500;
  transition: color 0.15s;
}

.nav-links a:hover {
  color: #1a1a1a;
}

/* ── LAYOUT ── */
main {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

section {
  padding: 3rem 0;
  border-bottom: 1px solid #e5e5e5;
}

section:last-child {
  border-bottom: none;
}

/* ── HERO ── */
.hero {
  padding-top: 7rem;
  padding-bottom: 3rem;
  text-align: center;
}

.hero h1 {
  font-size: 2.8rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  color: #1a1a1a;
  margin-bottom: 0.75rem;
}

.hero-sub {
  font-size: 1rem;
  color: #555;
  line-height: 1.8;
  margin-bottom: 1.5rem;
}

.hero-badges {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 1.5rem;
}

.badge {
  display: inline-block;
  padding: 0.25rem 0.65rem;
  font-size: 0.72rem;
  font-weight: 500;
  border: 1px solid #ddd;
  border-radius: 4px;
  color: #555;
  background: #fff;
}

.badge-orange {
  border-color: #e67e22;
  color: #e67e22;
  background: #fef5ec;
}

/* ── SPRINT INDICATOR (hero) ── */
.sprint-indicator {
  display: inline-block;
  padding: 0.5rem 1rem;
  font-size: 0.85rem;
  font-weight: 600;
  border-radius: 6px;
  background: #eef7ee;
  color: #2d7d2d;
  border: 1px solid #c3e6c3;
}

.sprint-indicator.completed {
  background: #f0f0f0;
  color: #666;
  border-color: #ddd;
}

.sprint-indicator:empty {
  display: none;
}

/* ── TYPOGRAPHY ── */
h2 {
  font-size: 1.6rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 1rem;
  color: #1a1a1a;
}

h3 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-top: 2rem;
  margin-bottom: 0.75rem;
  color: #1a1a1a;
}

p {
  margin-bottom: 0.75rem;
  color: #333;
}

ul {
  margin: 0.5rem 0 1rem 1.25rem;
  color: #333;
}

li {
  margin-bottom: 0.35rem;
}

strong {
  font-weight: 600;
  color: #1a1a1a;
}

code {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.85em;
  background: #f0f0f0;
  padding: 0.1em 0.35em;
  border-radius: 3px;
  color: #c7254e;
}

/* ── TABLES ── */
table {
  width: 100%;
  border-collapse: collapse;
  margin: 1rem 0;
  font-size: 0.88rem;
}

thead {
  background: #f5f5f5;
}

th {
  text-align: left;
  font-weight: 600;
  padding: 0.6rem 0.75rem;
  border-bottom: 2px solid #ddd;
  color: #333;
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

td {
  padding: 0.55rem 0.75rem;
  border-bottom: 1px solid #eee;
  color: #444;
}

tr:hover td {
  background: #fafafa;
}

/* ── DIAGRAMS ── */
.diagram-container {
  margin: 1.5rem 0;
  padding: 1.5rem;
  background: #fff;
  border: 1px solid #e5e5e5;
  border-radius: 8px;
  overflow-x: auto;
}

.diagram-container .mermaid {
  display: flex;
  justify-content: center;
}

/* ── SPRINT CARDS ── */
.sprint-cards {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-top: 1.5rem;
}

.sprint-card {
  padding: 1.25rem 1.5rem;
  background: #fff;
  border: 1px solid #e5e5e5;
  border-radius: 8px;
  border-left: 4px solid #ddd;
  transition: border-color 0.2s, box-shadow 0.2s;
}

.sprint-card.current {
  border-left-color: #2d7d2d;
  box-shadow: 0 0 0 1px #c3e6c3;
  background: #fcfefb;
}

.sprint-card.completed {
  border-left-color: #999;
  opacity: 0.7;
}

.sprint-card.completed .sprint-header h3::after {
  content: " (Completed)";
  font-size: 0.75rem;
  font-weight: 500;
  color: #999;
}

.sprint-card.current .sprint-header h3::after {
  content: " (Current)";
  font-size: 0.75rem;
  font-weight: 500;
  color: #2d7d2d;
}

.sprint-header {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 0.5rem;
}

.sprint-header h3 {
  margin: 0;
  font-size: 1.05rem;
}

.sprint-dates {
  font-size: 0.78rem;
  color: #888;
  font-weight: 500;
}

.sprint-goal {
  font-size: 0.88rem;
  color: #555;
  font-style: italic;
  margin-bottom: 0.75rem;
}

.sprint-card ul {
  margin-bottom: 0;
  font-size: 0.88rem;
}

/* ── SPRINT MILESTONE LABEL ── */
.sprint-milestone {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: #e67e22;
  background: #fef5ec;
  border: 1px solid #f5d5b0;
  border-radius: 4px;
  padding: 0.15rem 0.5rem;
  margin-bottom: 0.75rem;
}

/* ── FOOTER ── */
footer {
  max-width: 960px;
  margin: 0 auto;
  padding: 2rem 1.5rem;
  text-align: center;
  font-size: 0.8rem;
  color: #888;
  border-top: 1px solid #e5e5e5;
}

footer p {
  color: #888;
  margin-bottom: 0.25rem;
}

footer a {
  color: #666;
  text-decoration: none;
  transition: color 0.15s;
}

footer a:hover {
  color: #1a1a1a;
}

/* ── RESPONSIVE ── */
@media (max-width: 640px) {
  .nav-links {
    gap: 0.75rem;
  }

  .nav-links a {
    font-size: 0.72rem;
  }

  .hero h1 {
    font-size: 2rem;
  }

  h2 {
    font-size: 1.35rem;
  }

  .sprint-header {
    flex-direction: column;
  }

  table {
    font-size: 0.8rem;
  }

  th, td {
    padding: 0.4rem 0.5rem;
  }
}