/* ==========================================================================
   NiuFit Pre-Landing · Healthtech Design System (Sculpted Surface)
   ========================================================================== */

/* --- 1. Design Tokens --- */
:root {
  /* Brand Blues (Extracted from Logo identity) */
  --niufit-blue-950: #071126;
  --niufit-blue-900: #0d1a38;
  --niufit-blue-800: #17326c;
  --niufit-blue-700: #1d4ed8;
  --niufit-blue-600: #2563eb;
  --niufit-blue-500: #3b82f6;
  --niufit-blue-400: #60a5fa;
  --niufit-blue-200: #bfdbfe;
  --niufit-blue-100: #dbeafe;
  --niufit-blue-50: #eff6ff;
  
  /* Tinted Page Canvas */
  --color-bg: #f4f8fc;
  
  /* Sculpted Slate-Blue Surfaces */
  --surface-b2b: linear-gradient(168deg, #edf4fc 0%, #e0ebf7 100%);
  --surface-b2c: linear-gradient(168deg, #eef5fb 0%, #e1ebf6 100%);
  --surface-border: #ccdcee;
  --surface-border-hover: #93c5fd;
  
  /* Text System */
  --color-text-primary: #071126;
  --color-text-secondary: #475569;
  --color-text-tertiary: #64748b;
  --color-divider: rgba(186, 207, 233, 0.6);

  /* Typography */
  --font-sans: 'Plus Jakarta Sans', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;

  /* Radii */
  --radius-pill: 9999px;
  --radius-xl: 16px;
  --radius-lg: 12px;
  --radius-md: 8px;

  /* Shadows & Elevation */
  --shadow-subtle: 0 1px 3px 0 rgba(7, 17, 38, 0.03);
  --shadow-card: 
    inset 0 1px 0 rgba(255, 255, 255, 0.9),
    0 8px 24px -4px rgba(13, 26, 56, 0.06),
    0 2px 6px -1px rgba(37, 99, 235, 0.03);
  --shadow-card-hover: 
    inset 0 1px 0 rgba(255, 255, 255, 0.95),
    0 18px 36px -6px rgba(13, 26, 56, 0.11),
    0 4px 12px -2px rgba(37, 99, 235, 0.05);

  /* Transitions */
  --transition-smooth: 220ms cubic-bezier(0.16, 1, 0.3, 1);
  --transition-bounce: 260ms cubic-bezier(0.34, 1.56, 0.64, 1);
}

/* --- 2. Reset & Base Setup --- */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-family: var(--font-sans);
  background-color: var(--color-bg);
  color: var(--color-text-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

body {
  min-height: 100dvh;
  position: relative;
  overflow-x: hidden;
  display: flex;
  flex-direction: column;
}

/* --- 3. Atmosphere & Ambient Glow --- */
.ambient-glow {
  position: fixed;
  top: -12%;
  left: 50%;
  transform: translateX(-50%);
  width: 980px;
  height: 600px;
  background: radial-gradient(
    ellipse at 50% 10%,
    rgba(37, 99, 235, 0.12) 0%,
    rgba(59, 130, 246, 0.04) 45%,
    transparent 72%
  );
  pointer-events: none;
  z-index: 0;
}

/* --- 4. Main Page Container (Desktop Viewport Lock) --- */
.page-container {
  position: relative;
  z-index: 1;
  min-height: 100dvh;
  max-width: 1080px;
  width: 100%;
  margin: 0 auto;
  padding: 1.75rem 1.5rem 1.25rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  box-sizing: border-box;
}

/* --- 5. Header & Brand Identity --- */
.site-header {
  display: flex;
  align-items: center;
  justify-content: center;
  padding-bottom: 0.5rem;
}

.brand-link {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  text-decoration: none;
  transition: opacity var(--transition-smooth), transform var(--transition-smooth);
}

.brand-link:hover {
  opacity: 0.9;
  transform: translateY(-1px);
}

.brand-logo {
  display: block;
  width: 38px;
  height: 38px;
  border-radius: 9px;
  object-fit: cover;
  box-shadow: 0 2px 10px rgba(37, 99, 235, 0.22);
}

.brand-name {
  font-size: 1.25rem;
  font-weight: 800;
  letter-spacing: -0.035em;
  color: var(--niufit-blue-950);
}

/* --- 6. Main Content Area --- */
.main-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  max-width: 860px;
  margin: 0 auto;
  width: 100%;
  padding: 0.75rem 0 1.25rem;
}

/* --- 7. Hero Section --- */
.hero-section {
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  margin-bottom: 1.75rem;
}

.hero-title {
  font-size: clamp(2.1rem, 3.8vw, 3.15rem);
  font-weight: 800;
  line-height: 1.12;
  letter-spacing: -0.038em;
  color: var(--color-text-primary);
  margin-bottom: 0.85rem;
  max-width: 22ch;
}

.highlight-blue {
  color: var(--niufit-blue-600);
  display: inline;
}

.hero-subtitle {
  font-size: clamp(0.95rem, 1.35vw, 1.075rem);
  font-weight: 450;
  line-height: 1.55;
  color: var(--color-text-secondary);
  max-width: 44ch;
  margin: 0 auto 1.35rem;
}

/* Editorial Transition Prompt */
.prompt-wrap {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
}

.prompt-wrap::before,
.prompt-wrap::after {
  content: '';
  width: 28px;
  height: 1px;
  background: rgba(37, 99, 235, 0.28);
}

.prompt-text {
  font-size: 0.8125rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--niufit-blue-700);
}

/* --- 8. Route Grid & Sculpted Cards --- */
.route-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.35rem;
  width: 100%;
}

/* Route Card Base */
.route-card {
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-xl);
  padding: 1.6rem 1.65rem 1.35rem;
  text-decoration: none;
  color: inherit;
  box-shadow: var(--shadow-card);
  transition: 
    transform var(--transition-smooth),
    box-shadow var(--transition-smooth),
    border-color var(--transition-smooth);
  overflow: hidden;
  cursor: pointer;
  outline: none;
}

/* Specific Surface Tones */
.b2b-card {
  background: var(--surface-b2b);
}

.b2c-card {
  background: var(--surface-b2c);
}

/* Card Top Glow Line */
.card-glow {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2.5px;
  background: linear-gradient(90deg, transparent, var(--niufit-blue-500), transparent);
  opacity: 0;
  transition: opacity var(--transition-smooth);
}

/* Card Hover & Focus States */
.route-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-card-hover);
  border-color: var(--surface-border-hover);
}

.route-card:hover .card-glow {
  opacity: 1;
}

.route-card:active {
  transform: translateY(-1px) scale(0.996);
}

.route-card:focus-visible {
  outline: 2px solid var(--niufit-blue-600);
  outline-offset: 3px;
}

/* Card Header */
.card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1.1rem;
}

.card-icon-box {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(255, 255, 255, 0.7);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  box-shadow: 0 1px 3px rgba(7, 17, 38, 0.04);
  transition: transform var(--transition-bounce), background-color var(--transition-smooth);
}

.b2b-icon-box {
  color: var(--niufit-blue-700);
  border: 1px solid rgba(191, 219, 254, 0.8);
}

.b2c-icon-box {
  color: #0284c7;
  border: 1px solid rgba(186, 230, 253, 0.8);
}

.card-svg {
  width: 18px;
  height: 18px;
}

.route-card:hover .card-icon-box {
  transform: scale(1.08);
  background: rgba(255, 255, 255, 0.95);
}

.card-meta {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--color-text-tertiary);
}

/* Card Body */
.card-body {
  margin-bottom: 1.35rem;
}

.card-title {
  font-size: 1.175rem;
  font-weight: 750;
  letter-spacing: -0.025em;
  color: var(--color-text-primary);
  line-height: 1.3;
  margin-bottom: 0.45rem;
}

.card-description {
  font-size: 0.8875rem;
  font-weight: 400;
  line-height: 1.5;
  color: var(--color-text-secondary);
}

/* Card Footer & CTA */
.card-footer {
  margin-top: auto;
  padding-top: 0.85rem;
  border-top: 1px solid var(--color-divider);
}

.card-cta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  font-size: 0.8875rem;
  font-weight: 700;
  color: var(--niufit-blue-700);
  letter-spacing: -0.01em;
  transition: color var(--transition-smooth);
}

.cta-arrow {
  font-size: 1.05rem;
  display: inline-block;
  transition: transform var(--transition-bounce);
}

.route-card:hover .card-cta {
  color: var(--niufit-blue-600);
}

.route-card:hover .cta-arrow {
  transform: translateX(4px);
}

/* --- 9. Minimal Footer --- */
.site-footer {
  text-align: center;
  padding-top: 0.75rem;
}

.footer-copy {
  font-size: 0.8125rem;
  color: var(--color-text-tertiary);
  letter-spacing: -0.01em;
}

.footer-brand {
  font-weight: 600;
  color: var(--color-text-secondary);
}

/* --- 10. Responsive Design --- */

/* Laptop & Large Tablet (1024px - 1280px) */
@media (max-width: 1280px) {
  .page-container {
    max-width: 980px;
    padding: 1.5rem 1.5rem 1.25rem;
  }
}

/* Tablet (max-width: 860px) */
@media (max-width: 860px) {
  .page-container {
    padding: 1.35rem 1.25rem 1rem;
  }

  .main-content {
    max-width: 100%;
  }

  .route-grid {
    gap: 1.1rem;
  }

  .route-card {
    padding: 1.45rem 1.35rem 1.25rem;
  }

  .hero-section {
    margin-bottom: 1.5rem;
  }

  .hero-title {
    font-size: 2.15rem;
  }
}

/* Small Tablet & Large Mobile (max-width: 768px) */
@media (max-width: 768px) {
  .route-grid {
    grid-template-columns: 1fr;
    gap: 1rem;
    max-width: 480px;
    margin: 0 auto;
  }

  .route-card {
    padding: 1.35rem 1.35rem 1.2rem;
  }

  .hero-subtitle {
    max-width: 38ch;
  }
}

/* Mobile Devices (max-width: 480px) / iPhone 390px & 375px */
@media (max-width: 480px) {
  .page-container {
    padding: 1.1rem 0.95rem 1.35rem;
    min-height: 100dvh;
    justify-content: flex-start;
  }

  .site-header {
    padding-bottom: 0.35rem;
  }

  .brand-logo {
    width: 34px;
    height: 34px;
    border-radius: 8px;
  }

  .brand-name {
    font-size: 1.15rem;
  }

  .main-content {
    padding: 0.35rem 0 1rem;
  }

  .hero-section {
    margin-bottom: 1.25rem;
  }

  .hero-title {
    font-size: clamp(1.65rem, 7vw, 1.95rem);
    line-height: 1.16;
    margin-bottom: 0.65rem;
  }

  .hero-subtitle {
    font-size: 0.9rem;
    line-height: 1.5;
    margin-bottom: 1.1rem;
    max-width: 32ch;
  }

  .prompt-wrap {
    gap: 0.5rem;
  }

  .prompt-wrap::before,
  .prompt-wrap::after {
    width: 18px;
  }

  .prompt-text {
    font-size: 0.75rem;
    letter-spacing: 0.04em;
  }

  .route-grid {
    grid-template-columns: 1fr;
    gap: 0.85rem;
    max-width: 100%;
  }

  .route-card {
    padding: 1.2rem 1.15rem 1.05rem;
    border-radius: var(--radius-lg);
  }

  .card-header {
    margin-bottom: 0.85rem;
  }

  .card-icon-box {
    width: 34px;
    height: 34px;
  }

  .card-svg {
    width: 17px;
    height: 17px;
  }

  .card-meta {
    font-size: 0.68rem;
  }

  .card-body {
    margin-bottom: 1.1rem;
  }

  .card-title {
    font-size: 1.075rem;
    margin-bottom: 0.35rem;
  }

  .card-description {
    font-size: 0.825rem;
    line-height: 1.45;
  }

  .card-footer {
    padding-top: 0.75rem;
  }

  .card-cta {
    font-size: 0.825rem;
  }

  .site-footer {
    padding-top: 1.25rem;
  }

  .footer-copy {
    font-size: 0.75rem;
  }
}

/* --- 11. Accessibility & Motion Preferences --- */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}