/*
 * nav.css
 * Sticky navbar: hides on scroll-down, reappears on scroll-up.
 * Hamburger menu with staggered link animations.
 */

/* --- Sticky wrapper ------------------------------------------------- */
.nav-wrapper {
    position: sticky;
    top: 0;
    z-index: 200;
    background-color: rgba(255, 255, 255, 0.88);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid transparent;
    transition:
        transform 0.35s cubic-bezier(0.4, 0, 0.2, 1),
        background-color 0.4s ease,
        border-color 0.4s ease;
}

body.dark-mode .nav-wrapper {
    background-color: rgba(0, 0, 0, 0.88);
}

/* scrolled state — slight border for depth */
.nav-wrapper.scrolled {
    border-bottom-color: var(--border-color);
}

/* hidden state — slide up */
.nav-wrapper.nav-hidden {
    transform: translateY(-100%);
}

/* --- Nav inner layout ----------------------------------------------- */
nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: var(--nav-height);
    padding: 0 5%;
    max-width: 1400px;
    margin: 0 auto;
}

/* --- Logo ----------------------------------------------------------- */
.logo {
    font-family: var(--font-display);
    font-size: 1.55rem;
    font-weight: 900;
    letter-spacing: -0.04em;
    color: var(--text-color);
    transition: color 0.2s;
}

.logo span {
    color: var(--primary-blue);
}

/* --- Desktop links -------------------------------------------------- */
.nav-links {
    display: flex;
    gap: 28px;
    align-items: center;
}

.nav-links a {
    font-family: var(--font-body);
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-color);
    opacity: 0.75;
    transition: opacity 0.2s, color 0.2s;
    white-space: nowrap;
}

.nav-links a:hover {
    opacity: 1;
    color: var(--primary-blue);
}

/* --- CTA 3D button in nav ------------------------------------------- */
/* Wraps a .btn-3d-top inside an anchor — same mechanics as hero button */
.nav-btn-cta {
    /* override default btn-3d-container background for nav context */
    background-color: var(--primary-blue-dark) !important;
    border-radius: 15px !important;
    opacity: 1 !important;
    padding: 5px 0 0 0 !important; /* match btn-3d-container padding-top fix */
}

.nav-btn-cta .btn-3d-top {
    padding: 9px 18px;
    font-size: 0.88rem;
    border-radius: 12px;
}

/* --- Hamburger button ----------------------------------------------- */
.hamburger {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 40px;
    height: 40px;
    cursor: pointer;
    border: none;
    background: none;
    padding: 6px;
    border-radius: 10px;
    transition: background-color 0.2s;
    z-index: 201;
}

.hamburger:hover {
    background-color: var(--surface-color);
}

.hamburger span {
    display: block;
    height: 2.5px;
    background-color: var(--text-color);
    border-radius: 3px;
    transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1),
                opacity 0.3s ease,
                width 0.3s ease;
    transform-origin: center;
}

.hamburger span:nth-child(1) { width: 22px; }
.hamburger span:nth-child(2) { width: 16px; }
.hamburger span:nth-child(3) { width: 22px; }

/* X state */
.hamburger.open span:nth-child(1) {
    width: 22px;
    transform: translateY(7.5px) rotate(45deg);
}
.hamburger.open span:nth-child(2) {
    opacity: 0;
    transform: scaleX(0);
}
.hamburger.open span:nth-child(3) {
    width: 22px;
    transform: translateY(-7.5px) rotate(-45deg);
}

/* --- Mobile nav drawer ---------------------------------------------- */
@media (max-width: 1024px) {
    .hamburger { display: flex; }

    .nav-links {
        position: fixed;
        top: var(--nav-height);
        left: 0;
        right: 0;
        background: var(--card-bg);
        flex-direction: column;
        align-items: stretch;
        padding: var(--sp-3);
        gap: var(--sp-1);
        border-bottom: 1px solid var(--border-color);
        box-shadow: var(--shadow-lg);
        /* hidden by default */
        pointer-events: none;
        opacity: 0;
        transform: translateY(-8px);
        transition: opacity 0.28s ease, transform 0.28s cubic-bezier(0.4, 0, 0.2, 1);
    }

    .nav-links.active {
        pointer-events: auto;
        opacity: 1;
        transform: translateY(0);
    }

    .nav-links a {
        padding: 14px 16px;
        border-radius: var(--radius-sm);
        font-size: 1rem;
        opacity: 0;
        transform: translateX(-10px);
        transition: opacity 0.25s ease, transform 0.25s ease,
                    background-color 0.15s, color 0.15s;
    }

    /* stagger reveal */
    .nav-links.active a:nth-child(1)  { opacity: 0.85; transform: translateX(0); transition-delay: 0.04s; }
    .nav-links.active a:nth-child(2)  { opacity: 0.85; transform: translateX(0); transition-delay: 0.08s; }
    .nav-links.active a:nth-child(3)  { opacity: 0.85; transform: translateX(0); transition-delay: 0.12s; }
    .nav-links.active a:nth-child(4)  { opacity: 0.85; transform: translateX(0); transition-delay: 0.16s; }
    .nav-links.active a:nth-child(5)  { opacity: 0.85; transform: translateX(0); transition-delay: 0.20s; }
    .nav-links.active a:nth-child(6)  { opacity: 0.85; transform: translateX(0); transition-delay: 0.24s; }
    .nav-links.active a:nth-child(7)  { opacity: 0.85; transform: translateX(0); transition-delay: 0.28s; }
    /* 8th child = the 3D CTA button */
    .nav-links.active a:nth-child(8)  { opacity: 1;    transform: translateX(0); transition-delay: 0.32s; }

    .nav-links a:hover {
        opacity: 1;
        background-color: var(--surface-color);
        color: var(--primary-blue);
    }

    /* CTA button inside mobile drawer — must be block-level to stretch */
    .nav-links .nav-btn-cta {
        display: block;       /* inline-block won't stretch; block will */
        margin-top: var(--sp-1);
        text-align: center;
    }

    .nav-links .nav-btn-cta .btn-3d-top {
        display: block;
        width: 100%;
        text-align: center;
        padding: 12px 18px;
        box-sizing: border-box;
    }
}