:root {
  /* Colorful Food Theme Color palette */
  --cardio-wellness-bg: #FAF9F6; /* Warm cream */
  --cardio-wellness-surface: #FFFFFF; /* Pure white */
  --cardio-wellness-border: #E8E5DF; /* Pale sand border */
  --cardio-wellness-ink: #1B2B24; /* Deep moss forest color for typography */
  
  /* Primary accents */
  --cardio-wellness-accent-green: #2B7A53; /* Deep rich fresh green */
  --cardio-wellness-accent-red: #D13438; /* Vibrant red-berry tint */
  --cardio-wellness-accent-gold: #F0A500; /* Warm citrus yellow for stars */
  
  /* Gradients */
  --cardio-wellness-gradient-primary: linear-gradient(135deg, #173629 0%, #0A1C14 100%); /* Elegant forest health gradient */
  --cardio-wellness-gradient-coral: linear-gradient(135deg, #D13438 0%, #B82529 100%); /* Energy-packed warm red gradient */

  /* Fonts */
  --font-display: 'Montserrat', sans-serif;
  --font-body: 'Open Sans', sans-serif;

  /* Custom styles */
  --cardio-wellness-radius: 16px; /* Soft round border radius */
}

/* Scroll Progress indicator dynamics */
.scroll-progress {
  height: 4px;
  width: 0%;
  animation: cardio-progress-grow linear forwards;
  animation-timeline: scroll();
}

@keyframes cardio-progress-grow {
  to {
    width: 100%;
  }
}

/* CSS-only responsive burger transitions */
#cardio-menu-toggle:checked ~ .cardio-nav-deck {
  display: flex;
  flex-direction: column;
  position: absolute;
  top: 100%;
  left: 0;
  width: 100%;
  background: #ffffff;
  padding: 1.5rem;
  border-bottom: 2px solid var(--cardio-wellness-border);
  box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
  z-index: 40;
}

/* Scroll animations for sections (pure CSS, no JS) */
.cardio-content-row, .cardio-features-shelf, .cardio-feedback-zone, .cardio-form-station {
  animation: cardio-fade-snap linear both;
  animation-timeline: view();
  animation-range: entry 5% cover 30%;
}

@keyframes cardio-fade-snap {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Custom styling for inputs */
input, textarea {
  border: 1px solid var(--cardio-wellness-border);
  transition: all 0.3s ease;
}
input:focus, textarea:focus {
  border-color: var(--cardio-wellness-accent-green);
  box-shadow: 0 0 0 3px rgba(43, 122, 83, 0.15);
}

/* Standard accessibility active effects */
a:focus-visible, button:focus-visible {
  outline: 3px solid var(--cardio-wellness-accent-red);
  outline-offset: 2px;
}