/* ========================================
   Osteo+ Landing Page
   ======================================== */

:root {
  --color-bg: #0b0b0f;
  --color-bg-alt: #111118;
  --color-bg-card: #16161e;
  --color-bg-card-hover: #1c1c26;
  --color-text: #e8e8ed;
  --color-text-muted: #8b8b9e;
  --color-accent: #FBC02D;
  --color-accent-light: #FDD835;
  --color-accent-glow: rgba(251, 192, 45, 0.15);
  --color-orange: #E47200;
  --color-blue: #1E88E5;
  --color-red: #D32F2F;
  --color-border: rgba(255, 255, 255, 0.06);
  --color-border-hover: rgba(255, 255, 255, 0.12);
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  --font: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
}

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

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
}

body {
  font-family: var(--font);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  overflow-x: hidden;
}

.container {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 24px;
}

img { max-width: 100%; height: auto; }
a { text-decoration: none; color: inherit; }

/* ---- Buttons ---- */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font);
  font-weight: 600;
  border: none;
  cursor: pointer;
  border-radius: var(--radius-sm);
  transition: all 0.2s ease;
}

.btn-sm {
  padding: 8px 18px;
  font-size: 0.875rem;
  background: var(--color-accent);
  color: #000;
  border-radius: 100px;
}

.btn-sm:hover {
  background: var(--color-accent-light);
  transform: translateY(-1px);
}

.btn-primary {
  background: var(--color-accent);
  color: #000;
  border-radius: var(--radius-md);
}

.btn-primary:hover {
  background: var(--color-accent-light);
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(245, 158, 11, 0.3);
}

.btn-lg {
  padding: 16px 32px;
  font-size: 1.05rem;
}

.apple-icon {
  width: 20px;
  height: 20px;
}

.app-store-badge {
  display: inline-block;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.app-store-badge:hover {
  transform: translateY(-2px);
  opacity: 0.85;
}

.app-store-badge img {
  display: block;
  border-radius: 10px;
}

.star-filled {
  color: var(--color-accent);
  font-size: 1.1rem;
  font-variation-settings: 'FILL' 1;
}

.nav-logo-img {
  width: 32px;
  height: 32px;
  border-radius: 8px;
}

.footer-brand-logo {
  display: flex;
  align-items: center;
  gap: 8px;
}

/* ---- Badge ---- */

.badge {
  display: inline-block;
  padding: 6px 14px;
  font-size: 0.8rem;
  font-weight: 600;
  border-radius: 100px;
  background: var(--color-accent-glow);
  color: var(--color-accent);
  border: 1px solid rgba(245, 158, 11, 0.2);
}

.badge-outline {
  background: transparent;
  color: var(--color-text-muted);
  border-color: var(--color-border);
}

/* ---- Section ---- */

.section-header {
  text-align: center;
  max-width: 600px;
  margin: 0 auto 60px;
}

.section-tag {
  display: inline-block;
  padding: 4px 14px;
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  border-radius: 100px;
  background: var(--color-accent-glow);
  color: var(--color-accent);
  margin-bottom: 16px;
}

.section-header h2 {
  font-size: 2.2rem;
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 12px;
}

.section-header p {
  color: var(--color-text-muted);
  font-size: 1.1rem;
}

.accent {
  color: var(--color-accent);
}

/* ========================================
   NAV
   ======================================== */

.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 16px 0;
  transition: all 0.3s ease;
}

.nav.scrolled {
  background: rgba(11, 11, 15, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--color-border);
  padding: 10px 0;
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 1.2rem;
  font-weight: 800;
}

.nav-logo-icon {
  font-size: 1.4rem;
}

.nav-links {
  display: flex;
  gap: 32px;
}

.nav-links a {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--color-text-muted);
  transition: color 0.2s;
}

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

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--color-text);
  border-radius: 2px;
  transition: all 0.3s;
}

/* ========================================
   HERO
   ======================================== */

.hero {
  padding: 160px 0 80px;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -200px;
  left: 50%;
  transform: translateX(-50%);
  width: 800px;
  height: 800px;
  background: radial-gradient(circle, var(--color-accent-glow) 0%, transparent 70%);
  pointer-events: none;
}

.hero-inner {
  display: flex;
  align-items: center;
  gap: 60px;
}

.hero-content {
  flex: 1;
}

.hero-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 28px;
}

.hero h1 {
  font-size: 3.8rem;
  font-weight: 800;
  line-height: 1.08;
  letter-spacing: -0.02em;
  margin-bottom: 20px;
}

.hero-sub {
  font-size: 1.15rem;
  color: var(--color-text-muted);
  line-height: 1.7;
  max-width: 480px;
  margin-bottom: 32px;
}

.hero-cta {
  display: flex;
  gap: 16px;
  margin-bottom: 14px;
}

.hero-note {
  font-size: 0.85rem;
  color: var(--color-text-muted);
}

.hero-phone {
  flex-shrink: 0;
}

.phone-frame {
  width: 280px;
  border-radius: 36px;
  overflow: hidden;
  box-shadow:
    0 30px 80px rgba(0, 0, 0, 0.5),
    0 0 120px var(--color-accent-glow);
  position: relative;
  background: var(--color-bg);
}

.phone-frame img {
  display: block;
  width: 100%;
  height: auto;
}

/* ========================================
   PROOF BAR
   ======================================== */

.proof-bar {
  padding: 40px 0;
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
}

.proof-items {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 48px;
  flex-wrap: wrap;
}

.proof-item {
  text-align: center;
}

.proof-item strong {
  display: block;
  font-size: 1.8rem;
  font-weight: 800;
  color: var(--color-accent);
}

.proof-item span {
  font-size: 0.85rem;
  color: var(--color-text-muted);
}

.proof-divider {
  width: 1px;
  height: 40px;
  background: var(--color-border);
}

/* ========================================
   FEATURES
   ======================================== */

.features {
  padding: 100px 0;
}

.feature-main {
  display: flex;
  align-items: center;
  gap: 60px;
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: 48px;
  margin-bottom: 32px;
}

.feature-main-text {
  flex: 1;
}

.feature-main-text h3 {
  font-size: 1.6rem;
  font-weight: 700;
  margin-bottom: 12px;
}

.feature-main-text p {
  color: var(--color-text-muted);
  font-size: 1.05rem;
  line-height: 1.7;
}

.feature-main-visual {
  flex-shrink: 0;
  width: 160px;
  height: 160px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-accent-glow);
  border-radius: var(--radius-lg);
}

.feature-icon-large {
  font-size: 4rem;
  color: var(--color-accent);
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.feature-card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 32px;
  transition: all 0.3s ease;
}

.feature-card:hover {
  background: var(--color-bg-card-hover);
  border-color: var(--color-border-hover);
  transform: translateY(-4px);
}

.feature-card-icon {
  font-size: 2rem;
  margin-bottom: 16px;
  color: var(--color-accent);
}

.feature-card h4 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.feature-card p {
  color: var(--color-text-muted);
  font-size: 0.95rem;
  line-height: 1.6;
}

/* ========================================
   HOW IT WORKS
   ======================================== */

.how-it-works {
  padding: 100px 0;
  background: var(--color-bg-alt);
}

.steps {
  display: flex;
  align-items: flex-start;
  justify-content: center;
  gap: 24px;
}

.step {
  flex: 1;
  max-width: 280px;
  text-align: center;
}

.step-number {
  width: 56px;
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--color-accent);
  color: #000;
  font-size: 1.3rem;
  font-weight: 800;
  margin: 0 auto 20px;
}

.step h4 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.step p {
  color: var(--color-text-muted);
  font-size: 0.95rem;
  line-height: 1.6;
}

.step-arrow {
  padding-top: 16px;
  color: var(--color-text-muted);
  opacity: 0.3;
  flex-shrink: 0;
}

/* ========================================
   WHY US
   ======================================== */

.why-us {
  padding: 100px 0;
}

.why-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.why-card {
  text-align: center;
  padding: 32px 20px;
}

.why-icon {
  font-size: 2.4rem;
  margin-bottom: 16px;
  color: var(--color-accent);
}

.why-card h4 {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.why-card p {
  color: var(--color-text-muted);
  font-size: 0.9rem;
  line-height: 1.6;
}

/* ========================================
   AUDIENCE
   ======================================== */

.audience {
  padding: 100px 0;
  background: var(--color-bg-alt);
}

.audience-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 20px;
}

.audience-card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 28px 20px;
  text-align: center;
  transition: all 0.3s ease;
}

.audience-card:hover {
  border-color: var(--color-accent);
  transform: translateY(-4px);
}

.audience-icon {
  font-size: 2rem;
  margin-bottom: 14px;
  color: var(--color-accent);
}

.audience-card h4 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.audience-card p {
  color: var(--color-text-muted);
  font-size: 0.85rem;
  line-height: 1.5;
}

/* ========================================
   REVIEWS
   ======================================== */

.reviews {
  padding: 100px 0;
}

.review-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.review-card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 28px;
  transition: all 0.3s ease;
}

.review-card:hover {
  background: var(--color-bg-card-hover);
}

.review-stars {
  display: flex;
  gap: 2px;
  margin-bottom: 14px;
}

.review-card p {
  font-size: 0.95rem;
  line-height: 1.6;
  margin-bottom: 18px;
  color: var(--color-text);
}

.review-author strong {
  display: block;
  font-size: 0.9rem;
}

.review-author span {
  font-size: 0.8rem;
  color: var(--color-text-muted);
}

/* ========================================
   FAQ
   ======================================== */

.faq {
  padding: 100px 0;
  background: var(--color-bg-alt);
}

.faq-list {
  max-width: 680px;
  margin: 0 auto;
}

.faq-item {
  border-bottom: 1px solid var(--color-border);
}

.faq-item summary {
  padding: 20px 0;
  font-size: 1.05rem;
  font-weight: 600;
  cursor: pointer;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: color 0.2s;
}

.faq-item summary:hover {
  color: var(--color-accent);
}

.faq-item summary::after {
  content: '+';
  font-size: 1.4rem;
  font-weight: 300;
  color: var(--color-text-muted);
  transition: transform 0.3s;
}

.faq-item[open] summary::after {
  transform: rotate(45deg);
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item p {
  padding: 0 0 20px;
  color: var(--color-text-muted);
  font-size: 0.95rem;
  line-height: 1.7;
}

/* ========================================
   BONE ATLAS
   ======================================== */

.bone-atlas {
  padding: 100px 0;
  background: var(--color-bg-alt);
}

.atlas-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin-bottom: 32px;
}

.atlas-card {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  padding: 20px;
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: all 0.2s ease;
}

.atlas-card:hover {
  border-color: var(--color-accent);
  transform: translateY(-3px);
  background: var(--color-bg-card-hover);
}

.atlas-icon {
  color: var(--color-accent);
  font-size: 1.5rem;
  flex-shrink: 0;
  margin-top: 2px;
}

.atlas-card h4 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 4px;
}

.atlas-card p {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  line-height: 1.5;
}

.atlas-bottom {
  display: flex;
  gap: 24px;
  margin-bottom: 24px;
}

.atlas-browse {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--color-accent);
  transition: gap 0.2s;
}

.atlas-browse:hover {
  gap: 10px;
}

.atlas-browse .material-symbols-outlined {
  font-size: 1.1rem;
}

.atlas-personas {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  padding-top: 20px;
  border-top: 1px solid var(--color-border);
}

.atlas-persona-link {
  padding: 6px 16px;
  font-size: 0.8rem;
  font-weight: 600;
  border-radius: 100px;
  border: 1px solid var(--color-border);
  color: var(--color-text-muted);
  transition: all 0.2s;
}

.atlas-persona-link:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

/* ========================================
   FINAL CTA
   ======================================== */

.final-cta {
  padding: 100px 0;
}

.cta-inner {
  text-align: center;
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: 80px 40px;
  position: relative;
  overflow: hidden;
}

.cta-inner::before {
  content: '';
  position: absolute;
  top: -100px;
  left: 50%;
  transform: translateX(-50%);
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, var(--color-accent-glow) 0%, transparent 70%);
  pointer-events: none;
}

.cta-inner h2 {
  font-size: 2.4rem;
  font-weight: 800;
  margin-bottom: 12px;
  position: relative;
}

.cta-inner p {
  color: var(--color-text-muted);
  font-size: 1.1rem;
  margin-bottom: 32px;
  position: relative;
}

.cta-inner .btn {
  position: relative;
}

/* ========================================
   FOOTER
   ======================================== */

.footer {
  padding: 40px 0;
  border-top: 1px solid var(--color-border);
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 24px;
}

.footer-brand p {
  color: var(--color-text-muted);
  font-size: 0.85rem;
  margin-top: 4px;
}

.footer-links {
  display: flex;
  gap: 28px;
}

.footer-links a {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  transition: color 0.2s;
}

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

.footer-bottom {
  text-align: center;
  padding-top: 24px;
  border-top: 1px solid var(--color-border);
}

.footer-bottom p {
  font-size: 0.8rem;
  color: var(--color-text-muted);
}

.footer-bottom time {
  font-size: 0.75rem;
  color: var(--color-text-muted);
  opacity: 0.7;
}

/* ========================================
   ANIMATIONS
   ======================================== */

.fade-in {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ========================================
   RESPONSIVE
   ======================================== */

@media (max-width: 1024px) {
  .hero h1 { font-size: 3rem; }
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
  .why-grid { grid-template-columns: repeat(2, 1fr); }
  .audience-grid { grid-template-columns: repeat(3, 1fr); }
  .review-grid { grid-template-columns: repeat(2, 1fr); }
  .atlas-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  .nav-links { display: none; }
  .nav .btn-sm { display: none; }
  .nav-toggle { display: flex; }

  .nav-links.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: rgba(11, 11, 15, 0.95);
    backdrop-filter: blur(20px);
    padding: 24px;
    gap: 16px;
    border-bottom: 1px solid var(--color-border);
  }

  .hero {
    padding: 120px 0 60px;
  }

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

  .hero h1 {
    font-size: 2.6rem;
  }

  .hero-sub {
    margin: 0 auto 32px;
  }

  .hero-cta {
    justify-content: center;
  }

  .hero-phone {
    order: -1;
    margin-bottom: 32px;
  }

  .phone-frame {
    width: 220px;
    margin: 0 auto;
  }

  .hero-badges {
    justify-content: center;
  }

  .hero-note {
    text-align: center;
  }

  .section-header h2 {
    font-size: 1.8rem;
  }

  .feature-main {
    flex-direction: column;
    padding: 32px;
    text-align: center;
  }

  .feature-grid {
    grid-template-columns: 1fr;
  }

  .steps {
    flex-direction: column;
    align-items: center;
  }

  .step-arrow {
    transform: rotate(90deg);
    padding: 0;
  }

  .why-grid {
    grid-template-columns: 1fr 1fr;
  }

  .audience-grid {
    grid-template-columns: 1fr 1fr;
  }

  .review-grid {
    grid-template-columns: 1fr;
  }

  .atlas-grid {
    grid-template-columns: 1fr;
  }

  .atlas-bottom {
    flex-direction: column;
    gap: 12px;
  }

  .footer-inner {
    flex-direction: column;
    gap: 20px;
    text-align: center;
  }

  .footer-links {
    flex-wrap: wrap;
    justify-content: center;
  }

  .cta-inner {
    padding: 60px 24px;
  }

  .cta-inner h2 {
    font-size: 1.8rem;
  }

  .proof-items {
    gap: 24px;
  }

  .proof-divider {
    display: none;
  }

  .proof-items {
    display: grid;
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 480px) {
  .hero h1 {
    font-size: 2.1rem;
  }

  .audience-grid {
    grid-template-columns: 1fr;
  }

  .why-grid {
    grid-template-columns: 1fr;
  }
}