/* ===========================
   LAYOUT & NAVIGATION
   =========================== */

/* Main Content */
.main-content {
    opacity: 0;
    transition: opacity 0.8s ease-in;
}

.main-content.hidden {
    display: none;
}

.main-content.visible {
    display: block;
    opacity: 1;
}

/* Header Sticky */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: rgba(0, 0, 0, 0.45);
    background-image: var(--gradient-accent-soft);
    backdrop-filter: blur(16px);
    z-index: 1000;
    padding: 1.5rem 0;
    border-bottom: 1px solid var(--color-border);
    opacity: 0;
    transform: translateY(-100%);
    transition: opacity 0.5s ease, transform 0.5s ease;
}

.header.visible {
    opacity: 1;
    transform: translateY(0);
}

.nav {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

/* Logo */
.nav-logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--accent-primary);
    text-decoration: none;
    letter-spacing: 0.05em;
    display: none;
}

/* Menu hamburger - caché sur desktop */
.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    width: 40px;
    height: 40px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 0;
    z-index: 1001;
}

.hamburger,
.hamburger::before,
.hamburger::after {
    width: 25px;
    height: 2px;
    background-color: var(--text-primary);
    transition: all 0.3s ease;
    border-radius: 2px;
}

.hamburger {
    position: relative;
}

.hamburger::before,
.hamburger::after {
    content: '';
    position: absolute;
    left: 0;
}

.hamburger::before {
    transform: translateY(-8px);
}

.hamburger::after {
    transform: translateY(8px);
}

/* Animation du hamburger en X */
.mobile-menu-toggle.active .hamburger {
    background-color: transparent;
}

.mobile-menu-toggle.active .hamburger::before {
    transform: rotate(45deg);
}

.mobile-menu-toggle.active .hamburger::after {
    transform: rotate(-45deg);
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-left: auto;
}

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 500;
    letter-spacing: 0.5px;
    position: relative;
    transition: color 0.3s ease;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-accent);
    transition: width 0.3s ease;
}

.nav-link:hover {
    color: var(--accent-primary);
}

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

/* Container commun */
.container {
    max-width: 1200px;
    margin: 0 auto;
}

/* Section Title */
.section-title {
    font-size: clamp(2rem, 5vw, 3rem);
    font-weight: 300;
    color: var(--text-primary);
    margin-bottom: 4rem;
    letter-spacing: 1px;
}

.theme-toggle {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.4rem 0.9rem;
    border-radius: 999px;
    border: 1px solid var(--color-border-strong);
    background: var(--color-surface);
    color: var(--text-secondary);
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    cursor: pointer;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.theme-toggle:hover {
    transform: translateY(-1px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
}

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

/* Menu mobile */
@media (max-width: 768px) {
    .header {
        padding: 0.75rem 0;
    }

    .nav {
        padding: 0 1rem;
    }

    .nav-logo {
        display: block;
    }

    .mobile-menu-toggle {
        display: flex;
    }

    .nav-actions {
        position: fixed;
        top: 57px;
        left: 0;
        right: 0;
        flex-direction: column;
        gap: 0;
        background: var(--color-bg);
        backdrop-filter: blur(20px);
        padding: 0;
        margin: 0;
        max-height: 0;
        overflow: hidden;
        opacity: 0;
        transition: max-height 0.4s ease, opacity 0.3s ease;
        border-bottom: 1px solid var(--color-border);
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    }

    .nav-actions.active {
        max-height: 100vh;
        opacity: 1;
    }

    .nav-link {
        width: 100%;
        padding: 1.2rem 1.5rem;
        font-size: 1rem;
        border-bottom: 1px solid var(--color-border);
        text-align: left;
    }

    .nav-link::after {
        display: none;
    }

    .nav-link:hover {
        background: var(--color-surface);
        color: var(--accent-primary);
    }

    .theme-toggle {
        width: calc(100% - 3rem);
        margin: 1rem 1.5rem;
        justify-content: center;
    }

    .theme-toggle-text {
        display: inline;
    }
}

@media (max-width: 480px) {
    .header {
        padding: 0.6rem 0;
    }

    .nav {
        padding: 0 0.75rem;
    }

    .nav-actions {
        top: 50px;
    }

    .mobile-menu-toggle {
        width: 35px;
        height: 35px;
    }

    .hamburger,
    .hamburger::before,
    .hamburger::after {
        width: 22px;
    }
}