/* ============================================
   BioCalcHub — Homepage Stylesheet
   ============================================ */

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

:root {
  --green-deep:    #1a3a2a;
  --green-mid:     #2d6a4f;
  --green-accent:  #52b788;
  --green-light:   #b7e4c7;
  --green-pale:    #f0f7f2;

  --ink:           #1a2620;
  --ink-muted:     #4a6358;
  --ink-faint:     #8aada0;

  --surface:       #ffffff;
  --surface-alt:   #f5f9f6;
  --border:        #d4e6db;
  --border-light:  #e8f2ec;

  --soon-bg:       #f4f7f5;
  --soon-border:   #dde8e2;
  --soon-text:     #8aada0;

  --radius-sm:  6px;
  --radius-md:  12px;
  --radius-lg:  18px;

  --font-display: 'Fraunces', Georgia, serif;
  --font-body:    'DM Sans', system-ui, sans-serif;

  --max-w: 1060px;
}

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-body);
  background: var(--surface-alt);
  color: var(--ink);
  line-height: 1.65;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ---- Utility ---- */
.container {
  width: 100%;
  max-width: var(--max-w);
  margin-inline: auto;
  padding-inline: clamp(1.25rem, 5vw, 2.5rem);
}

/* ============================================
   HEADER
   ============================================ */
.site-header {
  background: var(--green-deep);
  padding: 1rem 0;
  position: sticky;
  top: 0;
  z-index: 10;
  border-bottom: 1px solid rgba(255,255,255,0.06);
}

.site-header .container {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.logo-mark {
  flex-shrink: 0;
  line-height: 0;
}

.site-name {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 600;
  color: #ffffff;
  letter-spacing: -0.01em;
}

/* ============================================
   HERO
   ============================================ */
.hero {
  background: var(--green-deep);
  padding: clamp(3rem, 8vw, 5.5rem) 0 clamp(2.5rem, 6vw, 4.5rem);
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 60% 80% at 110% 50%, rgba(82,183,136,0.12) 0%, transparent 60%),
    radial-gradient(ellipse 40% 60% at -10% 60%, rgba(45,106,79,0.4) 0%, transparent 55%);
  pointer-events: none;
}

.hero-inner {
  position: relative;
}

.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(2.1rem, 5vw, 3.4rem);
  font-weight: 600;
  color: #ffffff;
  line-height: 1.18;
  letter-spacing: -0.025em;
  max-width: 700px;
  margin-bottom: 1.5rem;
}

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

.hero-lead {
  font-size: clamp(1rem, 2vw, 1.125rem);
  color: rgba(255,255,255,0.78);
  max-width: 600px;
  margin-bottom: 1rem;
  line-height: 1.7;
}

.hero-note {
  font-size: 0.825rem;
  color: rgba(255,255,255,0.42);
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.hero-note::before {
  content: '';
  display: inline-block;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--green-accent);
  flex-shrink: 0;
}

/* ============================================
   CALCULATORS SECTION
   ============================================ */
.calculators {
  padding: clamp(2.5rem, 6vw, 4rem) 0;
}

.section-label {
  font-family: var(--font-body);
  font-size: 0.7rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin-bottom: 1.5rem;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.25rem;
}

/* ---- Base card ---- */
.calc-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  transition: border-color 0.2s, box-shadow 0.2s;
}

.calc-card.active:hover {
  border-color: var(--green-accent);
  box-shadow: 0 0 0 3px rgba(82,183,136,0.12);
}

.calc-card.coming-soon {
  background: var(--soon-bg);
  border-color: var(--soon-border);
  opacity: 0.85;
}

/* ---- Card icon ---- */
.card-icon {
  width: 56px;
  height: 56px;
  background: var(--green-pale);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.coming-soon .card-icon {
  background: var(--soon-border);
}

/* ---- Card body ---- */
.card-body {
  flex: 1;
}

.card-body h3 {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--ink);
  letter-spacing: -0.01em;
  margin-bottom: 0.5rem;
}

.coming-soon .card-body h3 {
  color: var(--soon-text);
}

.card-desc {
  font-size: 0.9rem;
  color: var(--ink-muted);
  line-height: 1.6;
  margin-bottom: 0.85rem;
}

.coming-soon .card-desc {
  color: var(--soon-text);
}

/* ---- Index pills ---- */
.index-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  list-style: none;
}

.index-list li {
  font-size: 0.7rem;
  font-weight: 500;
  letter-spacing: 0.05em;
  color: var(--green-mid);
  background: var(--green-pale);
  border: 1px solid var(--border);
  padding: 0.2rem 0.55rem;
  border-radius: 100px;
}

/* ---- Badge ---- */
.badge-soon {
  display: inline-block;
  font-size: 0.68rem;
  font-weight: 500;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--soon-text);
  background: var(--soon-border);
  padding: 0.2rem 0.6rem;
  border-radius: 100px;
  margin-bottom: 0.6rem;
}

/* ---- CTA button ---- */
.card-cta {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  align-self: flex-start;
  font-size: 0.875rem;
  font-weight: 500;
  color: #ffffff;
  background: var(--green-mid);
  padding: 0.6rem 1.1rem;
  border-radius: var(--radius-sm);
  text-decoration: none;
  transition: background 0.18s, transform 0.12s;
}

.card-cta:hover {
  background: var(--green-deep);
}

.card-cta:active {
  transform: scale(0.98);
}

.card-cta:focus-visible {
  outline: 3px solid var(--green-accent);
  outline-offset: 2px;
}

.card-cta.disabled {
  background: var(--soon-border);
  color: var(--soon-text);
  cursor: default;
  pointer-events: none;
}

/* ============================================
   ABOUT SECTION
   ============================================ */
.about {
  background: var(--green-deep);
  padding: clamp(2.5rem, 6vw, 4rem) 0;
}

.about-inner {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: clamp(2rem, 5vw, 4rem);
  align-items: center;
}

.about-text h2 {
  font-family: var(--font-display);
  font-size: clamp(1.4rem, 3vw, 1.9rem);
  font-weight: 600;
  color: #ffffff;
  letter-spacing: -0.015em;
  margin-bottom: 1rem;
}

.about-text p {
  font-size: 0.925rem;
  color: rgba(255,255,255,0.65);
  line-height: 1.75;
  max-width: 520px;
}

.about-text p + p {
  margin-top: 0.85rem;
}

/* ---- Stat block ---- */
.about-stat-block {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  flex-shrink: 0;
}

.stat {
  text-align: right;
}

.stat-num {
  display: block;
  font-family: var(--font-display);
  font-size: 2.2rem;
  font-weight: 600;
  color: var(--green-accent);
  line-height: 1;
  letter-spacing: -0.02em;
}

.stat-label {
  display: block;
  font-size: 0.75rem;
  color: rgba(255,255,255,0.42);
  margin-top: 0.25rem;
  letter-spacing: 0.02em;
}

/* ============================================
   FOOTER
   ============================================ */
.site-footer {
  background: #111e17;
  padding: 1.5rem 0;
  margin-top: auto;
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem;
  font-size: 0.8rem;
  color: rgba(255,255,255,0.35);
}

.footer-note {
  font-style: italic;
}

/* ============================================
   RESPONSIVE
   ============================================ */
@media (max-width: 680px) {
  .about-inner {
    grid-template-columns: 1fr;
  }

  .about-stat-block {
    flex-direction: row;
    flex-wrap: wrap;
    gap: 1rem 2rem;
  }

  .stat {
    text-align: left;
  }

  .footer-inner {
    flex-direction: column;
    text-align: center;
  }
}

@media (max-width: 420px) {
  .card-grid {
    grid-template-columns: 1fr;
  }
}

/* ============================================
   REDUCED MOTION
   ============================================ */
@media (prefers-reduced-motion: reduce) {
  .calc-card,
  .card-cta {
    transition: none;
  }
}