h1 {
    font-size: clamp(2rem, 5vw, 3rem);  /* min 32px, fluid, max 48px */  /* fluid scale */ 
    line-height: 1.2;                   /* 120% for compact heading */   /* tight but readable */ 
}

h2 {
    font-size: clamp(1.75rem, 4.5vw, 2.5rem);  /* min 28px, fluid, max 40px */ 
    line-height: 1.25;                         /* 125% */                       
}

h3 {
    font-size: clamp(1.5rem, 4vw, 2rem);       /* min 24px, fluid, max 32px */ 
    line-height: 1.3;                          /* 130% */                       
}

h4 {
    font-size: clamp(1.25rem, 3.5vw, 1.5rem);  /* min 20px, fluid, max 24px */ 
    line-height: 1.35;                         /* 135% */                       
}

h5 {
    font-size: clamp(1rem, 3vw, 1.25rem);      /* min 16px, fluid, max 20px */ 
    line-height: 1.35;                         /* 135% */                       
}

h6 {
    font-size: clamp(0.875rem, 2.5vw, 1rem);    /* min 14px, fluid, max 16px */ 
    line-height: 1.35;                          /* 135% */                       
}