/* Header */
.header {
    background: var(--bg-color);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
    transition: all 0.3s ease;
    padding: 10px 0;
    /* Space above and below */
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

#logo {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 0;
    /* remove excessive padding */
}

#f2s-logo {
    max-width: 160px;
    height: auto;
    object-fit: contain;
    display: block;
}

.logo:hover {
    transform: scale(1.05);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 30px;
    margin: 0;
    padding: 0;
}

.nav-item {
    position: relative;
}

.nav-link {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    padding: 8px 0;
    transition: all 0.3s ease;
    position: relative;
    display: inline-block;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    width: 0;
    height: 2px;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    transition: width 0.3s ease;
    margin-top: 5px;
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

.subscribe-btn {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    padding: 12px 24px;
    border: none;
    border-radius: 25px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: var(--shadow);
}

.subscribe-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 15px -3px rgba(37, 99, 235, 0.3);
}

/* Desktop by default */
.hamburger {
    display: none;
}

/* Mobile-first responsive adjustments */
@media (max-width: 768px) {
    .nav-container {
        flex-wrap: wrap;
        height: auto;
        padding: 10px 15px;
    }

    #logo {
        justify-content: flex-start;
        margin-bottom: 10px;
    }

    #f2s-logo {
        max-width: 140px;
    }

    nav {
        width: 100%;
        order: 3;
        display: none;
    }

    nav.active {
        display: block;
    }

    .nav-menu {
        flex-direction: column;
        gap: 10px;
        align-items: flex-start;
        margin-top: 10px;
    }

    .nav-link {
        padding: 10px 5px;
        font-size: 16px;
    }

    .subscribe-btn {
        padding: 10px 20px;
        font-size: 14px;
        margin-left: auto;
        order: 2;
    }

    /* Hamburger Button */
    .hamburger {
        display: block;
        font-size: 24px;
        background: none;
        border: none;
        color: var(--text-color);
        cursor: pointer;
        order: 1;
        margin-left: auto;
    }
}