:root {
    --nv-primary: #002e45;
    --nv-primary-deep: #001824;
    --nv-primary-soft: #0a4a63;
    --nv-accent: #ff8200;
    --nv-accent-soft: #ffab4d;
    --nv-accent-deep: #d66d00;
    --nv-text: #e6ecf3;
    --nv-muted: #8da2b8;
    --nv-border: rgba(255,255,255,0.08);
}
body { padding-top: 128px; }
@media (max-width: 991.98px) { body { padding-top: 88px; } }

.acad-nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: linear-gradient(180deg, var(--nv-primary) 0%, var(--nv-primary-deep) 100%);
    font-family: var(--body-font, 'Roboto'), sans-serif;
    box-shadow: 0 2px 0 var(--nv-border), 0 6px 24px -12px rgba(0,0,0,0.35);
    z-index: 1020;
}
.acad-nav::before {
    content: "";
    position: absolute;
    left: 0; right: 0; bottom: 0;
    height: 2px;
    background: linear-gradient(90deg, transparent 0%, var(--nv-accent) 20%, var(--nv-accent-soft) 50%, var(--nv-accent) 80%, transparent 100%);
    pointer-events: none;
}
.acad-nav::after {
    content: "";
    position: absolute; inset: 0;
    background-image:
        linear-gradient(rgba(255,255,255,0.025) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,0.025) 1px, transparent 1px);
    background-size: 44px 44px;
    mask-image: linear-gradient(90deg, transparent 0%, rgba(0,0,0,0.6) 20%, rgba(0,0,0,0.6) 80%, transparent 100%);
    -webkit-mask-image: linear-gradient(90deg, transparent 0%, rgba(0,0,0,0.6) 20%, rgba(0,0,0,0.6) 80%, transparent 100%);
    pointer-events: none;
}
.acad-nav .main-navigation,
.acad-nav .navbar,
.acad-nav .container {
    position: relative;
    z-index: 2;
    background: transparent !important;
}
.acad-nav .navbar { padding: 10px 0; }
.acad-nav .navbar-brand {
    padding: 6px 0;
    display: inline-flex;
    align-items: center;
    gap: 12px;
}
.acad-nav .navbar-brand img {
    max-height: 78px;
    width: auto;
    filter: drop-shadow(0 2px 6px rgba(0,0,0,0.25));
    transition: transform .25s ease;
}
.acad-nav .navbar-brand:hover img { transform: scale(1.03); }

.acad-nav .navbar-nav {
    gap: 0;
    align-items: center;
}
.acad-nav .nav-item { position: relative; }
.acad-nav .nav-link {
    color: var(--nv-text) !important;
    font-size: 13.5px !important;
    font-weight: 500;
    letter-spacing: 0.2px;
    padding: 9px 6px !important;
    border-radius: 2px;
    position: relative;
    transition: color .18s ease, background-color .18s ease;
    text-transform: none;
}
.acad-nav .nav-link::after {
    content: "";
    position: absolute;
    left: 6px;
    right: 6px;
    bottom: 3px;
    height: 2px;
    background: var(--nv-accent);
    border-radius: 2px;
    transform: scaleX(0);
    transform-origin: center;
    transition: transform .22s ease;
}
.acad-nav .nav-link:hover,
.acad-nav .nav-link:focus {
    color: #fff !important;
    background: rgba(255,255,255,0.04);
}
.acad-nav .nav-link:hover::after,
.acad-nav .nav-link.active::after {
    transform: scaleX(1);
}
.acad-nav .nav-link.dropdown-toggle::after {
    display: inline-block;
    width: 0; height: 0;
    margin-left: 6px;
    vertical-align: middle;
    content: "";
    border-top: 4px solid currentColor;
    border-right: 4px solid transparent;
    border-bottom: 0;
    border-left: 4px solid transparent;
    background: transparent;
    position: static;
    transform: none;
    border-radius: 0;
}
.acad-nav .dropdown-menu {
    background: linear-gradient(180deg, var(--nv-primary) 0%, var(--nv-primary-deep) 100%);
    border: 1px solid var(--nv-border);
    border-radius: 3px;
    padding: 8px;
    margin-top: 6px !important;
    box-shadow: 0 20px 40px -20px rgba(0,0,0,0.55);
    min-width: 220px;
}
.acad-nav .dropdown-menu::before {
    content: "";
    position: absolute;
    top: 0; left: 0; right: 0;
    height: 2px;
    background: var(--nv-accent);
    border-radius: 2px 2px 0 0;
    opacity: 0.7;
}
.acad-nav .dropdown-item {
    color: var(--nv-text);
    font-size: 13px;
    font-weight: 500;
    padding: 9px 12px;
    border-radius: 2px;
    display: flex;
    align-items: center;
    gap: 10px;
    transition: background-color .18s ease, color .18s ease;
}
.acad-nav .dropdown-item i {
    color: var(--nv-accent);
    width: 16px;
    text-align: center;
    font-size: 12px;
}
.acad-nav .dropdown-item:hover,
.acad-nav .dropdown-item:focus {
    background: rgba(255,130,0,0.14);
    color: #fff;
}

.acad-nav .nav-user {
    margin-left: 8px;
    padding: 9px 16px !important;
    border-radius: 2px;
    border: 1px solid rgba(255,130,0,0.35);
    background: rgba(255,255,255,0.04);
    display: inline-flex !important;
    align-items: center;
    gap: 10px;
}
.acad-nav .nav-user::before {
    content: "";
    width: 7px; height: 7px;
    border-radius: 50%;
    background: var(--nv-accent);
    box-shadow: 0 0 0 3px rgba(255,130,0,0.18);
}
.acad-nav .nav-user::after { margin-left: 4px; }
.acad-nav .nav-user:hover {
    background: rgba(255,255,255,0.08);
    border-color: rgba(255,130,0,0.35);
}

.acad-nav .navbar-toggler {
    border: 1.5px solid var(--nv-accent);
    background: var(--nv-accent);
    color: var(--nv-primary-deep);
    padding: 9px 14px;
    border-radius: 2px;
    transition: background-color .18s ease, color .18s ease, box-shadow .2s ease, transform .15s ease;
    box-shadow: 0 6px 16px -6px rgba(255,130,0,0.55);
}
.acad-nav .navbar-toggler:hover {
    background: var(--nv-accent-soft);
    border-color: var(--nv-accent-soft);
    transform: translateY(-1px);
}
.acad-nav .navbar-toggler:focus { box-shadow: 0 0 0 4px rgba(255,130,0,0.35); outline: none; }
.acad-nav .navbar-toggler-mobile-icon i { color: var(--nv-primary-deep); font-size: 18px; }

@media (max-width: 991.98px) {
    .acad-nav .navbar-brand img { max-height: 60px; }
    .acad-nav .navbar-collapse {
        margin-top: 14px;
        padding: 12px;
        border-top: 1px solid var(--nv-border);
        background: rgb(0 0 0 / 83%);
        border-radius: 0 0 3px 3px;
    }
    .acad-nav .navbar-nav { gap: 2px; align-items: stretch; }
    .acad-nav .nav-link {
        padding: 12px 14px !important;
        border-radius: 2px;
    }
    .acad-nav .nav-link::after {
        left: 0; right: auto; bottom: 50%;
        width: 3px; height: 18px;
        transform: scaleY(0);
        transform-origin: center;
        border-radius: 3px;
        margin-bottom: -9px;
    }
    .acad-nav .nav-link:hover::after,
    .acad-nav .nav-link.active::after { transform: scaleY(1); }
    .acad-nav .dropdown-menu {
        background: rgba(255,255,255,0.03);
        border: 1px solid var(--nv-border);
        margin-top: 2px !important;
        box-shadow: none;
    }
    .acad-nav .nav-login,
    .acad-nav .nav-user {
        margin-left: 0;
        margin-top: 6px;
        justify-content: center;
    }
}