:root {
    --header-height: clamp(70px, 10vw, 90px);
    --header-padding: clamp(8px, 1.5vw, 10px);
    --header-bg-color: #ffffff;
    --header-border-radius: 0;
    --header-box-shadow: 0 20px 40px rgba(0, 0, 0, 0.4);
    --header-link-color: #000;
    --header-link-hover-color: #6f8c4c;
    --header-icon-size: clamp(20px, 3vw, 24px);
    --header-icon-hover-color: #C66B6B;
}

/* Responsive header height adjustments */
@media (max-width: 480px) {
    :root {
        --header-height: 70px;
    }
}

@media (min-width: 481px) and (max-width: 768px) {
    :root {
        --header-height: 75px;
    }
}

@media (min-width: 769px) and (max-width: 1024px) {
    :root {
        --header-height: 80px;
    }
}

@media (min-width: 1025px) {
    :root {
        --header-height: 90px;
    }
}

#header-section {
    position: fixed;
    top: 0px;
    left: 0;
    width: 100%;
    max-width: 100vw;
    height: var(--header-height);
    min-height: 60px;
    max-height: 110px;
    background: var(--header-bg-color);
    border-radius: var(--header-border-radius);
    box-shadow: var(--header-box-shadow);
    padding: var(--header-padding);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    box-sizing: border-box;
}

.header-links a {
    color: var(--header-link-color);
    text-decoration: none;
    transition: color 0.3s ease, margin 0.3s ease, transform 0.3s ease;
    padding: 0 clamp(5px, 1vw, 10px);
    white-space: nowrap;
    margin: 0 clamp(8px, 2vw, 15px);
    font-size: clamp(0.9rem, 2vw, 1.2rem);
    font-weight: 600;
    position: relative;
    display: inline-block;
}

.header-links a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 50%;
    width: 0;
    height: 2px;
    background-color: #6f8c4c; /* Darker tree green */
    transition: width 0.3s ease, left 0.3s ease;
}

/* Responsive header link adjustments */
@media (max-width: 480px) {
    .header-links a {
        margin: 0 5px;
        font-size: 0.75rem;
        padding: 0 4px;
    }
}

@media (min-width: 481px) and (max-width: 768px) {
    .header-links a {
        margin: 0 8px;
        font-size: 0.85rem;
        padding: 0 6px;
    }
}

@media (min-width: 769px) and (max-width: 1024px) {
    .header-links a {
        margin: 0 12px;
        font-size: 1rem;
    }
}

@media (min-width: 1025px) and (max-width: 1440px) {
    .header-links a {
        margin: 0 15px;
        font-size: 1.1rem;
    }
}

@media (min-width: 1441px) {
    .header-links a {
        margin: 0 20px;
        font-size: 1.2rem;
    }
}

.header-links a:hover {
    color: var(--header-link-hover-color); /* Pink hover color */
    transform: translateY(-3px); /* Slight raise effect */
}

.header-links a:hover::after {
    width: 60%; /* Narrow underline */
    left: 20%; /* Keep centered under text */
}

/* Anchor offset handled by dedicated spacer */
#section1 {
    margin-top: 0;
}

.header-logo {
    position: absolute;
    left: clamp(10px, 2vw, 20px);
    top: 50%;
    transform: translateY(-50%);
    height: clamp(40px, 8vw, 70px);
    min-height: 35px;
    max-height: 80px;
    width: auto;
    background-color: #ffffff;
    border-radius: clamp(12px, 2vw, 18px);
    transition: transform 0.3s ease;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

/* Responsive logo adjustments */
@media (max-width: 480px) {
    .header-logo {
        height: 40px;
        left: 8px;
        border-radius: 10px;
        background-color: #ffffff;
        box-shadow: 0 2px 6px rgba(0, 0, 0, 0.1);
    }
}

@media (min-width: 481px) and (max-width: 768px) {
    .header-logo {
        height: 50px;
        left: 12px;
        border-radius: 14px;
        background-color: #ffffff;
        box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    }
}

@media (min-width: 769px) and (max-width: 1024px) {
    .header-logo {
        height: 60px;
        left: 16px;
        border-radius: 16px;
        background-color: #ffffff;
        box-shadow: 0 3px 10px rgba(0, 0, 0, 0.12);
    }
}

@media (min-width: 1025px) {
    .header-logo {
        height: 70px;
        left: 20px;
        border-radius: 18px;
        background-color: #ffffff;
        box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    }
}

.header-logo:hover {
    transform: translateY(-50%) scale(clamp(1.05, 1.1, 1.15));
    filter: none;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.2);
}

@media (max-width: 768px) {
    .header-logo:hover {
        transform: translateY(-50%) scale(1.08);
        box-shadow: 0 3px 12px rgba(0, 0, 0, 0.18);
    }
}