/* Header & Navigation - Compact */
header {
    background-color: rgba(255, 255, 255, 0.1); /* More transparent for glass effect */
    border-bottom: 1px solid rgba(255, 255, 255, 0.2); /* Subtle white border */
    padding: 0.5rem 0;  /* Reduced from 1rem to 0.5rem */
    text-align: center;
    position: sticky;
    top: 0;
    z-index: 1000;
    backdrop-filter: blur(20px) saturate(180%) brightness(1.1);
    -webkit-backdrop-filter: blur(20px) saturate(180%) brightness(1.1);
    transition: all 0.3s ease;
}

header h1 {
    margin: 0 0 clamp(4px, 1.25vw, 6px) 0;
    font-size: clamp(1.75rem, 3.8vw, 3.2rem);
    font-weight: 600;
    transition: font-size 0.3s ease, margin 0.3s ease;
}

header h2 {
    margin: 0;
    font-size: clamp(0.85rem, 1.8vw, 1.1rem);
    font-weight: 300;
    color: var(--secondary-text-light);
    transition: font-size 0.3s ease;
}

nav ul {
    list-style: none;
    padding: 0;
    margin: 0.25rem 0 0 0;  /* Reduced from 0.5rem */
    display: flex;
    justify-content: center;
    gap: 15px;  /* Reduced from 20px */
    transition: margin 0.3s ease, gap 0.3s ease;
}

nav ul li a {
    color: var(--nav-link-light);
    text-decoration: none;
    padding: clamp(4px, 1.25vw, 8px) clamp(8px, 1.5vw, 10px);
    border-radius: 5px;
    font-weight: 500;
    font-size: clamp(0.9rem, 1.5vw, 1rem);
    transition: color 0.2s ease, background-color 0.2s ease;
}

nav ul li a:hover {
    color: var(--nav-link-hover-light);
    background-color: rgba(0, 123, 255, 0.1);
}

/* Compact Header on Scroll */
header.compact {
    background-color: rgba(255, 255, 255, 0.15); /* Slightly more opaque for visibility */
    backdrop-filter: blur(25px) saturate(200%) brightness(1.05);
    -webkit-backdrop-filter: blur(25px) saturate(200%) brightness(1.05);
    padding: 0.15rem 0; /* Even tighter vertical padding */
}

header.compact h1 {
    margin: 0 0 0.08rem 0;
    font-size: 1.5rem;
}

header.compact h2 {
    font-size: 0.9rem;
}

header.compact nav {
    margin: 0.05rem 0 0 0; /* Minimal margin */
}

header.compact nav ul {
    gap: clamp(8px, 1.25vw, 12px);
}

header.compact nav ul li a {
    padding: clamp(3px, 1vw, 5px) clamp(5px, 1.2vw, 7px);
    font-size: clamp(0.85rem, 1.2vw, 0.95rem);
}

/* Compact container for tighter overall header */
header.compact .container {
    padding: 0 20px; /* Less horizontal padding */
}

/* Footer */
footer {
    text-align: center;
    padding: 2rem 0;
    margin-top: 2rem;
    color: var(--secondary-text-light);
}