/* ===========================
   Layout System
   Header, Footer, Grid
   =========================== */

/* === Container === */
.container {
    width: 100%;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--container-padding);
}

.container--narrow {
    max-width: var(--container-narrow);
}

.container--wide {
    max-width: var(--container-wide);
}

/* === Section === */
.section {
    padding: var(--space-20) 0;
}

.section--sm {
    padding: var(--space-12) 0;
}

.section--lg {
    padding: var(--space-32) 0;
}

.section--dark {
    background-color: var(--color-bg-primary);
    color: var(--color-text-primary);
}

.section--dark h2,
.section--dark h3,
.section--dark h4 {
    color: var(--color-text-primary);
}

.section--dark p {
    color: var(--color-text-secondary);
}

.section--premium {
    background: var(--color-bg-secondary);
    position: relative;
    overflow: hidden;
}

.section--premium::before {
    content: '';
    position: absolute;
    top: -10%;
    right: -10%;
    width: 40%;
    height: 40%;
    background: radial-gradient(circle, rgba(212, 175, 55, 0.05), transparent 70%);
    pointer-events: none;
}

.section--gray {
    background-color: var(--color-bg-secondary);
}

/* === Section Header === */
.section-header {
    text-align: center;
    max-width: 680px;
    margin: 0 auto var(--space-12);
}

.section-header__label {
    display: inline-block;
    font-size: var(--text-sm);
    font-weight: var(--font-semibold);
    color: var(--color-accent);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: var(--space-3);
}

.section-header__title {
    margin-bottom: var(--space-4);
}

.section-header__desc {
    font-size: var(--text-lg);
    color: var(--color-text-secondary);
    margin-bottom: 0;
}

/* === Grid System === */
.grid {
    display: grid;
    gap: var(--space-6);
}

.grid--2 {
    grid-template-columns: repeat(2, 1fr);
}

.grid--3 {
    grid-template-columns: repeat(3, 1fr);
}

.grid--4 {
    grid-template-columns: repeat(4, 1fr);
}

/* === Header === */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: var(--z-header);
    background: rgba(2, 6, 23, 0.7);
    -webkit-backdrop-filter: blur(16px);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    transition: all var(--transition-base);
}

.header.scrolled {
    background: rgba(2, 6, 23, 0.9);
    border-bottom-color: rgba(212, 175, 55, 0.2);
    box-shadow: var(--shadow-md);
}

.header__inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.header__logo {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    font-family: var(--font-heading);
    font-size: var(--text-2xl);
    font-weight: var(--font-extrabold);
    color: var(--color-white);
    text-decoration: none;
    letter-spacing: -0.02em;
}

.header__logo-icon {
    width: 36px;
    height: 36px;
    background: var(--gradient-accent);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-white);
    font-weight: var(--font-extrabold);
    font-size: var(--text-sm);
}

.header__nav {
    display: flex;
    align-items: center;
    gap: var(--space-1);
}

.header__link {
    display: inline-flex;
    align-items: center;
    padding: var(--space-2) var(--space-4);
    font-size: var(--text-sm);
    font-weight: var(--font-medium);
    color: var(--color-text-secondary);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
    text-decoration: none;
}

.header__link:hover,
.header__link.active {
    color: var(--color-accent);
    background-color: rgba(212, 175, 55, 0.1);
}

.header__cta {
    margin-left: var(--space-4);
}

/* Mobile menu toggle */
.header__menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    padding: var(--space-2);
    cursor: pointer;
    background: none;
    border: none;
}

.header__menu-btn span {
    display: block;
    width: 24px;
    height: 2px;
    background-color: var(--color-text-primary);
    border-radius: 2px;
    transition: all var(--transition-base);
}

.header__menu-btn.active span:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
}

.header__menu-btn.active span:nth-child(2) {
    opacity: 0;
}

.header__menu-btn.active span:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
}

/* Mobile navigation overlay */
.mobile-nav {
    display: none;
    position: fixed;
    top: 72px;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(255, 255, 255, 0.98);
    -webkit-backdrop-filter: blur(20px);
    backdrop-filter: blur(20px);
    z-index: var(--z-overlay);
    padding: var(--space-8) var(--space-6);
    opacity: 0;
    transform: translateY(-10px);
    transition: all var(--transition-base);
}

.mobile-nav.open {
    opacity: 1;
    transform: translateY(0);
}

.mobile-nav__link {
    display: block;
    padding: var(--space-4) 0;
    font-size: var(--text-lg);
    font-weight: var(--font-medium);
    color: var(--color-text-primary);
    text-decoration: none;
    border-bottom: 1px solid var(--color-gray-100);
    transition: color var(--transition-fast);
}

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

/* === Footer === */
.footer {
    background-color: var(--color-bg-dark);
    color: var(--color-text-inverse);
    padding: var(--space-16) 0 var(--space-8);
}

.footer__grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: var(--space-10);
    margin-bottom: var(--space-12);
}

.footer__brand-desc {
    font-size: var(--text-sm);
    color: var(--color-gray-400);
    line-height: var(--leading-relaxed);
    margin-bottom: var(--space-6);
    max-width: 320px;
}

.footer__social {
    display: flex;
    gap: var(--space-3);
}

.footer__social-link {
    width: 40px;
    height: 40px;
    border-radius: var(--radius-md);
    background-color: var(--color-bg-dark-secondary);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-gray-400);
    transition: all var(--transition-fast);
    text-decoration: none;
}

.footer__social-link:hover {
    background-color: var(--color-accent);
    color: var(--color-white);
}

.footer__heading {
    font-size: var(--text-sm);
    font-weight: var(--font-semibold);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: var(--space-6);
    color: var(--color-white);
}

.footer__list {
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
}

.footer__link {
    font-size: var(--text-sm);
    color: var(--color-gray-400);
    text-decoration: none;
    transition: color var(--transition-fast);
}

.footer__link:hover {
    color: var(--color-accent-light);
}

.footer__bottom {
    border-top: 1px solid var(--color-bg-dark-secondary);
    padding-top: var(--space-8);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.footer__copyright {
    font-size: var(--text-sm);
    color: var(--color-gray-500);
}

.footer__bottom-links {
    display: flex;
    gap: var(--space-6);
}

.footer__bottom-links a {
    font-size: var(--text-sm);
    color: var(--color-gray-500);
    text-decoration: none;
    transition: color var(--transition-fast);
}

.footer__bottom-links a:hover {
    color: var(--color-gray-300);
}

/* === Responsive === */
@media (max-width: 1024px) {
    .grid--4 {
        grid-template-columns: repeat(2, 1fr);
    }

    .footer__grid {
        grid-template-columns: 1fr 1fr;
        gap: var(--space-8);
    }
}

@media (max-width: 768px) {
    h1 {
        font-size: var(--text-4xl);
    }

    h2 {
        font-size: var(--text-3xl);
    }

    h3 {
        font-size: var(--text-2xl);
    }

    .section {
        padding: var(--space-12) 0;
    }

    .section--lg {
        padding: var(--space-20) 0;
    }

    .grid--2,
    .grid--3,
    .grid--4 {
        grid-template-columns: 1fr;
    }

    .header__nav {
        display: none;
    }

    .header__cta {
        display: none;
    }

    .header__menu-btn {
        display: flex;
    }

    .mobile-nav {
        display: block;
    }

    .footer__grid {
        grid-template-columns: 1fr;
    }

    .footer__bottom {
        flex-direction: column;
        gap: var(--space-4);
        text-align: center;
    }
}

@media (max-width: 480px) {
    h1 {
        font-size: var(--text-3xl);
    }

    h2 {
        font-size: var(--text-2xl);
    }

    .container {
        padding: 0 var(--space-4);
    }
}