/* ==================== HEADER ==================== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--header-height);
    padding: 0 var(--container-padding);
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: rgba(5, 5, 5, 0.8);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid transparent;
    z-index: var(--z-header);
    transition: all 0.3s var(--ease-out-expo);
}

[data-theme="light"] .header {
    background: rgba(250, 250, 250, 0.8);
}

.header.scrolled {
    border-bottom-color: var(--color-border);
    background: rgba(5, 5, 5, 0.95);
}

[data-theme="light"] .header.scrolled {
    background: rgba(250, 250, 250, 0.95);
}

/* Logo */
.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    text-decoration: none;
}

.logo__image {
    height: 36px;
    width: auto;
}

.logo__text {
    font-family: var(--font-mono);
    font-size: 16px;
    font-weight: 600;
    color: var(--color-text);
}

.logo__text::before {
    content: './';
    color: var(--color-accent);
}

/* Navigation */
.nav {
    display: flex;
    align-items: center;
    gap: 32px;
}

.nav__list {
    display: flex;
    align-items: center;
    gap: 8px;
}

@media (max-width: 768px) {
    .nav__list {
        position: fixed;
        top: var(--header-height);
        left: 0;
        right: 0;
        background: var(--color-bg-secondary);
        border-bottom: 1px solid var(--color-border);
        padding: 16px;
        flex-direction: column;
        gap: 8px;
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: all 0.3s var(--ease-out-expo);
    }
    
    .nav__list.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }
}

.nav__link {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 8px 16px;
    font-family: var(--font-mono);
    font-size: 13px;
    color: var(--color-text-secondary);
    border-radius: var(--radius-sm);
    transition: all 0.2s ease;
}

.nav__link:hover {
    color: var(--color-text);
    background: var(--color-bg-tertiary);
}

.nav__link.active {
    color: var(--color-accent);
}

.nav__link svg {
    width: 16px;
    height: 16px;
    opacity: 0.7;
}

@media (max-width: 768px) {
    .nav__link {
        width: 100%;
        padding: 12px 16px;
    }
}

/* Special MFlip Game Link */
.nav__link--game {
    color: var(--color-accent);
    background: var(--color-accent-glow);
    border: 1px solid rgba(0, 255, 136, 0.2);
}

.nav__link--game:hover {
    background: rgba(0, 255, 136, 0.15);
    border-color: var(--color-accent);
}

.nav__link--game svg {
    opacity: 1;
    color: var(--color-accent);
}

/* SEELIO link */
.nav__link--seelio {
    color: #38bdf8;
    background: rgba(56, 189, 248, 0.1);
    border: 1px solid rgba(56, 189, 248, 0.2);
}

.nav__link--seelio:hover {
    background: rgba(56, 189, 248, 0.15);
    border-color: #38bdf8;
    color: #38bdf8;
}

.nav__link--seelio svg {
    opacity: 1;
    color: #38bdf8;
}

/* BILLEVO app link */
.nav__link--app {
    color: var(--color-accent-secondary);
    background: rgba(0, 204, 255, 0.1);
    border: 1px solid rgba(0, 204, 255, 0.2);
}

.nav__link--app:hover {
    background: rgba(0, 204, 255, 0.15);
    border-color: var(--color-accent-secondary);
    color: var(--color-accent-secondary);
}

.nav__link--app svg {
    opacity: 1;
    color: var(--color-accent-secondary);
}

/* Header Actions */
.header__actions {
    display: flex;
    align-items: center;
    gap: 12px;
}

.theme-toggle {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-sm);
    background: var(--color-bg-tertiary);
    border: 1px solid var(--color-border);
    color: var(--color-text-secondary);
    transition: all 0.2s ease;
}

.theme-toggle:hover {
    color: var(--color-accent);
    border-color: var(--color-accent);
}

.theme-toggle svg {
    width: 18px;
    height: 18px;
}

/* Dark/Light icons */
[data-theme="dark"] .theme-toggle .icon-sun { display: block; }
[data-theme="dark"] .theme-toggle .icon-moon { display: none; }
[data-theme="light"] .theme-toggle .icon-sun { display: none; }
[data-theme="light"] .theme-toggle .icon-moon { display: block; }

/* Language Toggle */
.lang-toggle {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-sm);
    background: var(--color-bg-tertiary);
    border: 1px solid var(--color-border);
    color: var(--color-text-secondary);
    font-family: var(--font-mono);
    font-size: 12px;
    font-weight: 600;
    transition: all 0.2s ease;
    cursor: pointer;
}

.lang-toggle:hover {
    color: var(--color-accent);
    border-color: var(--color-accent);
}

/* Command Palette Button */
.cmd-btn {
    display: none;
    align-items: center;
    gap: 8px;
    padding: 8px 12px;
    font-family: var(--font-mono);
    font-size: 12px;
    color: var(--color-text-muted);
    background: var(--color-bg-tertiary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    transition: all 0.2s ease;
}

@media (min-width: 768px) {
    .cmd-btn { display: flex; }
}

.cmd-btn:hover {
    color: var(--color-text);
    border-color: var(--color-accent);
}

.cmd-btn kbd {
    display: flex;
    align-items: center;
    gap: 2px;
    padding: 2px 6px;
    font-size: 11px;
    background: var(--color-bg);
    border-radius: 4px;
}

/* Mobile Menu Toggle */
.mobile-menu {
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 40px;
    height: 40px;
    padding: 8px;
    background: var(--color-bg-tertiary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
}

@media (min-width: 769px) {
    .mobile-menu { display: none; }
}

.mobile-menu span {
    display: block;
    width: 100%;
    height: 2px;
    background: var(--color-text);
    border-radius: 1px;
    transition: all 0.3s ease;
}

.mobile-menu.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.mobile-menu.active span:nth-child(2) {
    opacity: 0;
}

.mobile-menu.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

/* Back Link (for subpages) */
.back-link {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 16px;
    font-family: var(--font-mono);
    font-size: 13px;
    color: var(--color-text-secondary);
    background: var(--color-bg-tertiary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    transition: all 0.2s ease;
}

.back-link:hover {
    color: var(--color-text);
    border-color: var(--color-accent);
}

.back-link svg {
    width: 16px;
    height: 16px;
}