:root {
  /* Foundation — deep blues */
  --qb-deep-space:     #050B1F;
  --qb-quantum-navy:   #0A1F4A;
  --qb-royal:          #1E3A8A;
  --qb-ink:            #0B1A2B;

  /* Signature accent — dark-mode variant */
  --qb-sky-dark:       #7DD3FC;
  --qb-electric-blue:  #3B82F6;

  /* Signature accent — light-mode variant */
  --qb-sky-light:      #0EA5E9;
  --qb-cobalt:         #2563EB;

  /* Neutrals */
  --qb-cool-white:     #F0F4FF;
  --qb-mist:           #F4F6FA;
  --qb-slate:          #94A3B8;
  --qb-graphite:       #6B7280;

  /* Canonical gradient strings */
  --qb-gradient-accent-dark:      linear-gradient(90deg,  #7DD3FC 0%, #3B82F6 100%);
  --qb-gradient-accent-dark-135:  linear-gradient(135deg, #7DD3FC 0%, #3B82F6 100%);
  --qb-gradient-accent-light:     linear-gradient(90deg,  #0EA5E9 0%, #2563EB 100%);
  --qb-gradient-accent-light-135: linear-gradient(135deg, #0EA5E9 0%, #2563EB 100%);
  --qb-gradient-hero:             linear-gradient(135deg, #050B1F 0%, #0A1F4A 60%, #1E3A8A 100%);
}