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

:root {
  --blue: #2563eb;
  --blue-dark: #1d4ed8;
  --blue-light: #eff6ff;
  --text: #111827;
  --muted: #6b7280;
  --border: #e5e7eb;
  --bg: #ffffff;
  --radius: 12px;
  --shadow: 0 1px 3px rgba(0,0,0,.08), 0 8px 24px rgba(0,0,0,.06);
}

html { scroll-behavior: smooth; }

body {
  font-family: 'Inter', system-ui, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  font-size: 1rem;
}

a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }
img { max-width: 100%; display: block; }

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  border-radius: 8px;
  cursor: pointer;
  transition: background .15s, transform .1s, box-shadow .15s;
  text-decoration: none;
  border: none;
  gap: .5rem;
}
.btn:active { transform: translateY(1px); }

.btn-primary {
  background: var(--blue);
  color: #fff;
}
.btn-primary:hover { background: var(--blue-dark); box-shadow: 0 4px 14px rgba(37,99,235,.35); }

.btn-white {
  background: #fff;
  color: var(--blue);
}
.btn-white:hover { background: #f0f6ff; }

.btn-sm  { padding: .45rem 1rem;  font-size: .875rem; }
.btn-lg  { padding: .85rem 2rem;  font-size: 1.05rem; }

/* ===== Header / Nav ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255,255,255,.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}

.nav {
  display: flex;
  align-items: center;
  gap: 2rem;
  height: 64px;
}

.logo {
  display: flex;
  align-items: center;
  gap: .5rem;
  font-weight: 700;
  font-size: 1rem;
  white-space: nowrap;
  color: var(--text);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 1.75rem;
  margin-left: auto;
}

.nav-links a {
  font-size: .9rem;
  color: var(--muted);
  font-weight: 500;
  transition: color .15s;
}
.nav-links a:hover { color: var(--text); }

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  margin-left: auto;
  padding: .25rem;
}
.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: transform .2s, opacity .2s;
}

/* ===== Hero ===== */
.hero {
  padding: 5rem 0 4rem;
  background: linear-gradient(160deg, #f0f6ff 0%, #ffffff 60%);
}

.hero-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: center;
}

.badge {
  display: inline-block;
  background: var(--blue-light);
  color: var(--blue);
  font-size: .8rem;
  font-weight: 600;
  padding: .3rem .8rem;
  border-radius: 999px;
  margin-bottom: 1.25rem;
  letter-spacing: .02em;
}

.hero-text h1 {
  font-size: clamp(2rem, 4vw, 2.75rem);
  font-weight: 800;
  line-height: 1.15;
  margin-bottom: 1.25rem;
  letter-spacing: -.02em;
}

.hero-sub {
  font-size: 1.1rem;
  color: var(--muted);
  margin-bottom: 2rem;
  max-width: 440px;
}

.hero-note {
  margin-top: .75rem;
  font-size: .85rem;
  color: var(--muted);
}

/* Plan preview card */
.hero-card {
  display: flex;
  justify-content: flex-end;
}

.plan-preview {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 1.5rem;
  width: 100%;
  max-width: 340px;
}

.week-label {
  display: block;
  font-weight: 700;
  font-size: .8rem;
  text-transform: uppercase;
  letter-spacing: .08em;
  color: var(--blue);
  margin-bottom: 1rem;
}

.run-row {
  display: flex;
  align-items: center;
  gap: .75rem;
  padding: .45rem 0;
  border-bottom: 1px solid var(--border);
  font-size: .875rem;
}
.run-row:last-child { border-bottom: none; }

.day {
  width: 30px;
  font-weight: 600;
  color: var(--muted);
  flex-shrink: 0;
}

.run-desc { flex: 1; }

.run-tag {
  font-size: .7rem;
  font-weight: 600;
  padding: .15rem .5rem;
  border-radius: 4px;
  flex-shrink: 0;
}
.run-tag.easy  { background: #dcfce7; color: #15803d; }
.run-tag.tempo { background: #fef9c3; color: #a16207; }
.run-tag.long  { background: #fee2e2; color: #b91c1c; }

/* ===== Stats strip ===== */
.stats-strip {
  background: var(--blue);
  padding: 2.5rem 0;
}

.stats-inner {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
  text-align: center;
}

.stat strong {
  display: block;
  font-size: 1.5rem;
  font-weight: 800;
  color: #fff;
}
.stat span {
  font-size: .85rem;
  color: rgba(255,255,255,.75);
  margin-top: .25rem;
}

/* ===== Section shared ===== */
.section-title {
  font-size: clamp(1.6rem, 3vw, 2.1rem);
  font-weight: 800;
  text-align: center;
  margin-bottom: .75rem;
  letter-spacing: -.02em;
}
.section-sub {
  text-align: center;
  color: var(--muted);
  font-size: 1rem;
  margin-bottom: 3rem;
}

/* ===== How it works ===== */
.how-it-works { padding: 5rem 0; }

.steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
  margin-bottom: 3rem;
  counter-reset: steps;
}

.step {
  text-align: center;
}

.step-icon {
  width: 52px;
  height: 52px;
  border-radius: 50%;
  background: var(--blue-light);
  color: var(--blue);
  font-weight: 800;
  font-size: 1.25rem;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 1.25rem;
}

.step h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: .5rem;
}

.step p {
  color: var(--muted);
  font-size: .925rem;
}

.cta-center { text-align: center; }

/* ===== Features ===== */
.features {
  background: #f9fafb;
  padding: 5rem 0;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.feature-card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.75rem;
  transition: box-shadow .2s;
}
.feature-card:hover { box-shadow: var(--shadow); }

.feature-icon {
  font-size: 1.75rem;
  margin-bottom: 1rem;
}

.feature-card h3 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: .5rem;
}

.feature-card p {
  font-size: .9rem;
  color: var(--muted);
  line-height: 1.55;
}

/* ===== FAQ ===== */
.faq { padding: 5rem 0; }

.faq-inner { max-width: 700px; margin: 0 auto; }

.faq-list { display: flex; flex-direction: column; gap: 0; }

.faq-item {
  border-bottom: 1px solid var(--border);
  padding: 1.4rem 0;
}
.faq-item:first-child { border-top: 1px solid var(--border); }

.faq-item dt {
  font-weight: 700;
  font-size: 1rem;
  margin-bottom: .5rem;
}

.faq-item dd {
  color: var(--muted);
  font-size: .925rem;
  line-height: 1.6;
}

/* ===== Final CTA ===== */
.final-cta {
  background: var(--blue);
  padding: 5rem 0;
  text-align: center;
}

.final-cta h2 {
  font-size: clamp(1.75rem, 3.5vw, 2.5rem);
  font-weight: 800;
  color: #fff;
  margin-bottom: 1rem;
}

.final-cta p {
  color: rgba(255,255,255,.8);
  font-size: 1.05rem;
  margin-bottom: 2rem;
}

/* ===== Footer ===== */
.site-footer {
  background: #111827;
  padding: 2.5rem 0;
}

.footer-inner {
  display: flex;
  align-items: center;
  gap: 2rem;
  flex-wrap: wrap;
}

.footer-logo {
  color: #fff;
  font-weight: 700;
  font-size: .95rem;
}

.footer-nav {
  display: flex;
  gap: 1.5rem;
  margin-left: auto;
}
.footer-nav a {
  font-size: .875rem;
  color: rgba(255,255,255,.6);
  transition: color .15s;
}
.footer-nav a:hover { color: #fff; }

.footer-copy {
  width: 100%;
  font-size: .8rem;
  color: rgba(255,255,255,.35);
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .hero-inner { grid-template-columns: 1fr; }
  .hero-card { display: none; }
  .hero-text h1 { font-size: 2rem; }

  .steps { grid-template-columns: 1fr; }
  .features-grid { grid-template-columns: 1fr 1fr; }
  .stats-inner { grid-template-columns: 1fr 1fr; gap: 2rem; }

  .nav-links { display: none; flex-direction: column; }
  .nav-toggle { display: flex; }

  .nav-links.open {
    display: flex;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: #fff;
    border-bottom: 1px solid var(--border);
    padding: 1rem 1.5rem;
    gap: 1rem;
    box-shadow: 0 4px 16px rgba(0,0,0,.08);
  }

  .footer-inner { flex-direction: column; align-items: flex-start; }
  .footer-nav { margin-left: 0; flex-wrap: wrap; }
}

@media (max-width: 480px) {
  .features-grid { grid-template-columns: 1fr; }
  .stats-inner { grid-template-columns: 1fr 1fr; }
}