/* ==========================================
   NAVIGATION & SCROLL RAIL
   ========================================== */
.nav-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 1.5rem 2rem;
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    align-items: center;
    gap: 0.8rem;
}

.scroll-nav {
    position: fixed;
    top: 50%;
    right: var(--scroll-rail-offset);
    transform: translateY(-50%);
    z-index: 2000;
    pointer-events: auto;
    padding-left: 12rem;
    width: auto;
    height: var(--scroll-rail-height);
}

.section-scroll-track {
    position: absolute;
    right: 0;
    width: 28px;
    height: 100%;
    display: flex;
    align-items: center;
}

body.intro-active .scroll-nav {
    opacity: 0;
    visibility: hidden;
}

.section-scroll-line {
    position: relative;
    width: var(--scroll-rail-width);
    height: 100%;
    margin: 0 auto;
    background: var(--text-color);
    border-radius: 999px;
    opacity: var(--scroll-rail-opacity-idle);
    transition: opacity 0.35s ease;
}

.section-scroll-track.is-scrolling .section-scroll-line {
    opacity: var(--scroll-rail-opacity-active);
}

.section-scroll-dot {
    position: absolute;
    left: 50%;
    width: var(--scroll-rail-dot-size);
    height: var(--scroll-rail-dot-size);
    background: var(--text-color);
    border-radius: 50%;
    transform: translate(-50%, -50%);
    transition: background-color 0.25s ease, box-shadow 0.25s ease;
}

.section-scroll-dot.active {
    background: var(--accent-color);
    box-shadow: 0 0 6px rgba(255, 0, 0, 0.35);
}

.section-scroll-current {
    position: absolute;
    left: 50%;
    width: var(--scroll-rail-current-width);
    height: var(--scroll-rail-dot-size);
    background: var(--accent-color);
    border-radius: 999px;
    transform: translate(-50%, -50%);
    box-shadow: 0 0 8px color-mix(in srgb, var(--accent-color) 70%, transparent);
}

/* ==========================================
   NAV BAR
   ========================================== */
.main-nav {
    position: absolute;
    left: 50%;
    bottom: 4em;
    transform: translateX(-50%);
    width: min(92vw, 1200px);
    z-index: 900;
    background: transparent;
    backdrop-filter: none;
    box-shadow: none;
    display: block;
    margin: 0 auto;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.45s ease;
}

.main-nav.nav-visible {
    opacity: 1;
    pointer-events: auto;
}

.nav-buttons {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.9rem;
    width: 100%;
}

.nav-button,
.nav-button::before,
.nav-button::after {
    border-radius: 2em !important;
}

.nav-button {
    letter-spacing: 0.5px;
    min-width: 5rem;
    text-align: center;
    white-space: nowrap;
}

.nav-button.active {
    color: var(--accent-color) !important;
    border-left: 1px solid var(--accent-color);
    border-right: 1px solid var(--accent-color);
    box-shadow: 0 0 12px rgba(255, 0, 0, 0.25);
}

.logo {
    font-family: 'Nasalization', sans-serif;
    font-size: 2em;
    font-weight: bold;
    color: #fff;
    letter-spacing: 1px;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-menu a {
    font-weight: 100;
    color: #fff;
    text-decoration: none;
    transition: color 0.3s ease;
    padding: 0.5rem 0;
    position: relative;
}

.nav-menu a.active {
    color: var(--accent-color);
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: color-mix(in srgb, var(--accent-color) 75%, transparent);
    transition: width 0.3s ease;
}

.nav-menu a:hover {
    color: color-mix(in srgb, var(--accent-color) 85%, var(--heading-color));
}

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

.nav-toggle {
    display: none;
    flex-direction: column;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
}

.nav-toggle span {
    width: 25px;
    height: 3px;
    background: #fff;
    margin: 3px 0;
    transition: all 0.3s ease;
}


/* ==========================================
   MOBILE NAV OVERLAY
   ========================================== */
.mobile-nav-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.78);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s ease;
    z-index: 1200;
    padding: 1.5rem;
}

.mobile-nav-overlay.open {
    opacity: 1;
    pointer-events: auto;
}

.mobile-nav-panel {
    width: min(520px, 92vw);
    background: rgba(10, 10, 16, 0.95);
    border: 1px solid color-mix(in srgb, var(--heading-color) 20%, transparent);
    border-radius: 1.2rem;
    box-shadow: 0 14px 40px rgba(0, 0, 0, 0.55);
    padding: 1.5rem 1.25rem 1.25rem;
    display: grid;
    gap: 0.75rem;
    justify-items: center;
}

.mobile-nav-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
    gap: 1rem;
}

.mobile-nav-title {
    font-family: 'Nasalization', sans-serif;
    font-size: 1.1rem;
    letter-spacing: 0.5px;
}

.mobile-nav-close {
    background: transparent;
    color: var(--heading-color);
    border: 1px solid color-mix(in srgb, var(--heading-color) 40%, transparent);
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: grid;
    place-items: center;
    cursor: pointer;
    transition: transform 0.2s ease, border-color 0.2s ease;
}

.mobile-nav-close:hover,
.mobile-nav-close:focus-visible {
    border-color: var(--accent-color);
    color: var(--accent-color);
    transform: scale(1.05);
}

.mobile-nav-buttons {
    width: 100%;
    display: grid;
    gap: 0.65rem;
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.mobile-nav-buttons .nav-button {
    width: 100%;
    justify-content: center;
}

body.nav-overlay-open {
    overflow: hidden;
}

/* ==========================================
   BACK TO TOP BUTTON
   ========================================== */
.back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 60px;
    height: 60px;
    background: transparent;
    border: none;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    z-index: 950;
    padding: 0;
    display: flex;
    align-items: center;
    justify-content: center;
}

.back-to-top img {
    width: 100%;
    height: 100%;
    filter: drop-shadow(0 4px 15px rgba(0, 0, 0, 0.5));
    transition: all 0.3s ease;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    transform: translateY(-5px);
}

.back-to-top:hover img {
    filter: drop-shadow(0 6px 20px rgba(255, 0, 0, 0.8));
    transform: scale(1.1);
}

/* ==========================================
   RESPONSIVE NAV & RAIL
   ========================================== */
@media (max-width: 1024px) {
    .nav-container {
        padding: 1rem 1.5rem;
    }
}

@media (max-width: 768px) {
    .back-to-top {
        width: 45px;
        height: 45px;
        bottom: 1.5rem;
        right: 1.5rem;
    }

    .main-nav {
        display: none;
    }

    .scroll-nav {
        display: none;
    }
}

@media (min-width: 769px) {

    body,
    html {
        scrollbar-width: thin;
        scrollbar-color: transparent transparent;
    }

    body::-webkit-scrollbar,
    html::-webkit-scrollbar {
        width: 1px;
    }

    body::-webkit-scrollbar-thumb,
    html::-webkit-scrollbar-thumb {
        background: transparent !important;
        border: none;
        box-shadow: none;
    }

    body::-webkit-scrollbar-track,
    html::-webkit-scrollbar-track {
        background: transparent;
    }
}