.nav {
    position: sticky;
    top: 0;
    left: 0;
    right: 0;
    z-index: 10;
    background: var(--c-bg-nav);
    border-bottom: 1px solid var(--c-border);
    transition: box-shadow .25s ease;
}
.nav--scrolled {
    box-shadow: 0 2px 24px rgba(0,0,0,.10);
}

.nav__inner {
    max-width: var(--max-w);
    margin: 0 auto;
    padding: 20px var(--pad) 21px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 32px;
}

.nav__logo {
    display: flex;
    align-items: baseline;
    gap: 5px;
    text-decoration: none;
    flex-shrink: 0;
}
.nav__logo-brand {
    font-family: var(--f-body);
    font-size: 17px;
    font-weight: 700;
    color: var(--c-dark);
    letter-spacing: -0.01em;
}
.nav__logo-sep {
    font-size: 10px;
    color: var(--c-blue);
    margin: 0 2px;
}
.nav__logo-academy {
    font-family: 'Mulish', sans-serif;
    font-weight: 300;
    font-size: 17px;
    color: var(--c-text-3);
    letter-spacing: -0.02em;
}

.nav__menu { flex: 1; display: flex; justify-content: center; }
.nav__list {
    display: flex;
    align-items: center;
    gap: 64px;
}
.nav__link {
    font-family: var(--f-mono);
    font-size: 14px;
    font-weight: 400;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    color: var(--c-dark);
    transition: color .15s;
}
.nav__link:hover { color: var(--c-blue); }

.nav__cta { flex-shrink: 0; }

.nav__burger {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 28px;
    height: 28px;
    flex-shrink: 0;
    background: none;
    border: none;
    cursor: pointer;
}
.nav__burger-line {
    display: block;
    width: 100%;
    height: 2px;
    background: var(--c-dark);
    border-radius: 2px;
    transition: transform .25s, opacity .25s;
}
.nav__burger--active .nav__burger-line:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav__burger--active .nav__burger-line:nth-child(2) { opacity: 0; }
.nav__burger--active .nav__burger-line:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

.nav__logo-img {
    height: 18px;
    width: auto;
}

.subnav {
    background: var(--c-bg-nav);
    border-bottom: 1px solid var(--c-border);
}
.subnav__inner {
    max-width: var(--max-w);
    margin: 0 auto;
    padding: 0 var(--pad);
    height: 60px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 24px;
}
.subnav__tag {
    font-family: var(--f-mono);
    font-size: 12px;
    font-weight: 400;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--c-blue);
}
.subnav__date {
    font-family: var(--f-mono);
    font-size: 14px;
    font-weight: 500;
    letter-spacing: 0.05em;
    color: var(--c-blue);
    text-decoration: underline;
    transition: opacity .15s;
}
.subnav__date:hover { opacity: .75; }

@media (max-width: 1023px) {
    .nav__list { gap: 36px; }
}

@media (max-width: 767px) {
    .nav__inner { padding: 16px var(--pad-sm); }
    .nav__burger { display: flex; }
    .nav__cta { display: none; }

    .nav__menu {
        display: block;
        pointer-events: none;
        position: absolute;
        top: 100%;
        left: 0; right: 0;
        background: var(--c-bg-nav);
        border-bottom: 1px solid var(--c-border);
        padding: 24px var(--pad-sm) 28px;
        transform: scaleY(0%);
        transform-origin: top center;
        transition: transform 0.3s, opacity 0.3s;
    }
    .nav__menu--open {
        opacity: 1;
        pointer-events: all;
        transform: scaleY(100%);
    }
    .nav__list { flex-direction: column; align-items: flex-start; gap: 20px; }

    .subnav__inner {
        padding: 0 var(--pad-sm);
        height: auto;
        flex-direction: column;
        align-items: flex-start;
        gap: 4px;
        padding-top: 12px;
        padding-bottom: 12px;
    }
    .subnav__date { font-size: 12px; }
}

@media (max-width: 390px) {
    .nav__inner    { padding: 16px; }
    .subnav__inner { padding: 10px 16px; }
    .subnav__tag   { font-size: 10px; }
    .subnav__date  { font-size: 10px; }
}