/* ===== HEADER & NAVIGATION ===== */
.header {
    position: fixed;
    top: var(--spacing-sm);
    left: 50%;
    transform: translateX(-50%);
    width: 94%;
    max-width: 1400px;
    z-index: 1000;
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.45) 0%, rgba(255, 255, 255, 0.05) 100%);
    backdrop-filter: blur(40px) saturate(200%);
    -webkit-backdrop-filter: blur(40px) saturate(200%);
    border: 1px solid rgba(255, 255, 255, 0.4);
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: var(--radius-full);
    padding: 0.5rem 2rem;
    height: auto;
    transition: all var(--transition-medium);
    box-shadow: 0 12px 36px rgba(0, 0, 0, 0.2), inset 0 1px 0 rgba(255, 255, 255, 0.8);
}

.header.scrolled {
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.75) 0%, rgba(255, 255, 255, 0.25) 100%);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.08), inset 0 1px 0 rgba(255, 255, 255, 0.9);
    border-color: rgba(255, 255, 255, 0.6);
    padding: 0.35rem 2rem;
}

body.dark-mode .header {
    background: linear-gradient(135deg, rgba(30, 30, 30, 0.6) 0%, rgba(10, 10, 10, 0.2) 100%);
    border-color: rgba(255, 255, 255, 0.1);
    box-shadow: 0 12px 36px rgba(255, 255, 255, 0.15), inset 0 1px 0 rgba(255, 255, 255, 0.3);
}

body.dark-mode .header.scrolled {
    background: linear-gradient(135deg, rgba(40, 40, 40, 0.75) 0%, rgba(20, 20, 20, 0.3) 100%);
    border-color: rgba(255, 255, 255, 0.15);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.6), inset 0 1px 0 rgba(255, 255, 255, 0.2);
}

.header-content {
    display: grid;
    grid-template-columns: auto 1fr auto;
    align-items: center;
    width: 100%;
    max-width: none;
    height: 100%;
    gap: 1rem;
}

.header-right-actions {
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

.nav-desktop {
    display: flex;
    align-items: center;
    gap: 2rem;
    justify-content: center;
}

/* Logo */
.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    z-index: 2;
    flex-shrink: 0;
}

.logo-img {
    height: 56px;
    width: auto;
    object-fit: contain;
    transition: height var(--transition-medium);
}

.header.scrolled .logo-img {
    height: 44px;
}

.logo-light { display: block; }
.logo-dark { display: none; }

body.dark-mode .logo-light { display: none; }
body.dark-mode .logo-dark { display: block; }

/* Desktop Nav - centered in middle column */
.nav-desktop {
    display: flex;
    gap: 0.5rem;
    align-items: center;
    justify-content: center;
}

.nav-desktop a {
    position: relative;
    color: var(--color-text-main);
    font-size: 1rem;
    font-weight: 600;
    padding: 0.5rem 1.1rem;
    border-radius: var(--radius-full);
    transition: color var(--transition-fast), opacity var(--transition-fast);
    z-index: 1;
}

.nav-desktop a::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.8) 0%, rgba(255, 255, 255, 0.3) 100%);
    border-radius: var(--radius-full);
    z-index: -1;
    opacity: 0;
    transform: scale(0.85);
    transition: opacity var(--transition-medium), transform var(--transition-medium);
    box-shadow: inset 0 1px 2px rgba(255, 255, 255, 0.9), 0 8px 18px rgba(0, 0, 0, 0.15);
    backdrop-filter: blur(10px);
}

body.dark-mode .nav-desktop a::before {
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.15) 0%, rgba(255, 255, 255, 0.05) 100%);
    box-shadow: inset 0 1px 2px rgba(255, 255, 255, 0.1), 0 4px 12px rgba(0, 0, 0, 0.3);
}

.nav-desktop a:hover {
    color: var(--color-text-main);
    opacity: 1;
}

.nav-desktop a:hover::before {
    opacity: 1;
    transform: scale(1);
}

/* Header Actions */
.header-actions {
    display: flex;
    gap: 0.5rem;
    align-items: center;
    z-index: 2;
    flex-shrink: 0;
}

/* Theme Toggle */
.theme-toggle-btn {
    position: relative;
    width: 38px;
    height: 38px;
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-text-main);
    transition: color var(--transition-fast), background var(--transition-fast), box-shadow var(--transition-fast);
    overflow: hidden;
}

.theme-toggle-btn:hover {
    background: rgba(0, 0, 0, 0.04);
    box-shadow: inset 0 1px 2px rgba(0, 0, 0, 0.05);
}

body.dark-mode .theme-toggle-btn:hover {
    background: rgba(255, 255, 255, 0.08);
    box-shadow: inset 0 1px 2px rgba(255, 255, 255, 0.1);
}

.theme-toggle-btn svg {
    width: 20px;
    height: 20px;
    transition: transform 0.5s cubic-bezier(0.34, 1.56, 0.64, 1), opacity 0.3s ease;
    position: absolute;
}

.theme-toggle-btn .sun-icon {
    opacity: 1;
    transform: rotate(0deg) scale(1);
}

.theme-toggle-btn .moon-icon {
    opacity: 0;
    transform: rotate(-90deg) scale(0.5);
}

body.dark-mode .theme-toggle-btn .sun-icon {
    opacity: 0;
    transform: rotate(90deg) scale(0.5);
}

body.dark-mode .theme-toggle-btn .moon-icon {
    opacity: 1;
    transform: rotate(0deg) scale(1);
}

/* Login Button */
.btn-login {
    color: var(--color-text-main);
    font-size: 1rem;
    font-weight: 600;
    padding: 0.5rem 1rem;
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.btn-login:hover {
    background: rgba(0, 0, 0, 0.04);
    box-shadow: inset 0 1px 2px rgba(0, 0, 0, 0.05);
}

body.dark-mode .btn-login:hover {
    background: rgba(255, 255, 255, 0.08);
    box-shadow: inset 0 1px 2px rgba(255, 255, 255, 0.1);
}

/* CTA Button */
.btn-cta {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.6rem 1.4rem;
    background: var(--color-text-main);
    color: var(--color-bg-body);
    font-weight: 600;
    font-size: 0.9rem;
    border-radius: var(--radius-full);
    transition: all var(--transition-medium);
    position: relative;
    overflow: hidden;
}

.btn-cta::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(255,255,255,0.2) 0%, transparent 50%);
    opacity: 0;
    transition: opacity var(--transition-medium);
}

.btn-cta:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.15);
    opacity: 0.9;
}

.btn-cta:hover::before {
    opacity: 1;
}

.btn-cta:active {
    transform: translateY(0);
}

/* Mobile Menu Toggle */
.menu-toggle {
    display: none;
    color: var(--color-text-main);
    width: 40px;
    height: 40px;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-md);
    transition: background var(--transition-fast);
}

.menu-toggle:hover {
    background: rgba(0, 0, 0, 0.06);
}

body.dark-mode .menu-toggle:hover {
    background: rgba(255, 255, 255, 0.1);
}

/* Mobile Navigation Overlay */
.mobile-nav {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background: var(--glass-bg);
    backdrop-filter: blur(30px);
    -webkit-backdrop-filter: blur(30px);
    z-index: 999;
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition-medium), visibility var(--transition-medium);
    padding-top: calc(var(--header-height) + 1rem);
}

.mobile-nav.open {
    opacity: 1;
    visibility: visible;
}

.mobile-nav-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    padding: 2rem;
}

.mobile-nav-content a {
    font-size: 1.25rem;
    font-weight: 500;
    color: var(--color-text-main);
    padding: 1rem 2rem;
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
    width: 100%;
    text-align: center;
}

.mobile-nav-content a:hover {
    background: rgba(var(--color-primary-rgb), 0.08);
    color: var(--color-primary);
}

.mobile-nav-actions {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    width: 100%;
    margin-top: 1.5rem;
    padding: 0 1rem;
}

/* ===== FOOTER ===== */
.footer {
    background-color: var(--color-bg-card);
    border-top: 1px solid var(--color-border);
    padding-bottom: var(--spacing-md);
}

.footer-content {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
}

.footer-brand .logo-img {
    height: 48px;
    margin-bottom: 1rem;
}

.footer-brand p {
    color: var(--color-text-muted);
    max-width: 300px;
    font-size: 0.9rem;
    line-height: 1.6;
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-md);
}

.link-group h4 {
    color: var(--color-text-main);
    margin-bottom: var(--spacing-sm);
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    font-weight: 600;
}

.link-group a {
    display: block;
    color: var(--color-text-muted);
    margin-bottom: 0.5rem;
    font-size: 0.9rem;
    transition: color var(--transition-fast);
}

.link-group a:hover {
    color: var(--color-primary);
}

.copyright {
    border-top: 1px solid var(--color-border);
    padding-top: var(--spacing-md);
    text-align: center;
    color: var(--color-text-muted);
    font-size: 0.85rem;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
    .nav-desktop,
    .header-actions {
        display: none;
    }

    .menu-toggle {
        display: flex;
    }

    .mobile-nav {
        display: block;
    }

    .header {
        padding: 0.5rem 1rem;
        width: 96%;
    }

    .footer-content {
        grid-template-columns: 1fr;
    }

    .footer-links {
        grid-template-columns: 1fr 1fr;
    }
}