/**
 * ======================================================
 * İşletme Dersleri UI Design System
 * Sidebar — eKampüs tarzı (açık tema)
 * ======================================================
 */
.sidebar {
    width: 100%;
    display: flex;
    flex-direction: column;
    gap: var(--space-lg);
    padding: var(--space-lg) var(--space-md);
    background: #EEF0F3;
    border-right: 1px solid #E1E4E9;
}
/* ---------------- Logo ---------------- */
.logo {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}
.logo-icon {
    width: 42px;
    height: 42px;
    border-radius: 50%;
    display: grid;
    place-items: center;
    font-family: var(--font-mono);
    font-weight: 700;
    font-size: 18px;
    color: #FFFFFF;
    background: #1B3A5B;
}
.logo-text {
    display: flex;
    flex-direction: column;
}
.logo-text strong {
    font-family: var(--font-display);
    font-size: var(--font-section);
    color: #1F2733;
    letter-spacing: .2px;
}
.logo-text span {
    font-family: var(--font-mono);
    font-size: 10.5px;
    letter-spacing: 1px;
    text-transform: uppercase;
    color: #8A93A0;
}
/* ---------------- Nav kartı ---------------- */
.sidebar-nav {
    display: flex;
    flex-direction: column;
    gap: 4px;
    background: #FFFFFF;
    border-radius: 20px;
    padding: var(--space-sm);
    box-shadow: 0 2px 10px rgba(20, 30, 45, 0.06);
}
.nav-item {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    padding: 13px 16px;
    border: none;
    background: transparent;
    border-radius: 999px;
    cursor: pointer;
    transition: .18s;
    color: #5B6472;
    font-family: var(--font-body);
    font-weight: 600;
    font-size: var(--font-body-size);
    text-align: left;
}
.nav-item:hover {
    background: #F1F3F6;
    color: #1F2733;
}
.nav-item.active {
    background: #1B3A5B;
    color: #FFFFFF;
    box-shadow: 0 4px 12px rgba(27, 58, 91, 0.35);
}
.nav-icon {
    width: 20px;
    text-align: center;
    flex-shrink: 0;
}
/* ---------------- Nav Submenu (Dersler > Programlar) ---------------- */
.nav-submenu {
    display: flex;
    flex-direction: column;
    gap: 2px;
    margin: 2px 0 6px 34px;
    padding-left: var(--space-sm);
    border-left: 2px solid #E1E4E9;
    max-height: 240px;
    overflow-y: auto;
    scrollbar-width: thin;
    scrollbar-color: #D3D8DF transparent;
}
.nav-submenu::-webkit-scrollbar {
    width: 5px;
}
.nav-submenu::-webkit-scrollbar-thumb {
    background: #D3D8DF;
    border-radius: var(--radius-sm);
}
.nav-subitem {
    padding: 8px 10px;
    border: none;
    background: transparent;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: .18s;
    color: #8A93A0;
    font-family: var(--font-body);
    font-size: 13px;
    text-align: left;
}
.nav-subitem:hover {
    background: #F1F3F6;
    color: #1F2733;
}
.nav-subitem.active {
    color: #1B3A5B;
    background: #E7ECF2;
    font-weight: 600;
}
@media (max-width: 900px) {
    .sidebar {
        flex-direction: row;
        align-items: center;
        overflow-x: auto;
        border-right: none;
        border-bottom: 1px solid #E1E4E9;
        padding: var(--space-sm);
    }
    .sidebar-nav {
        flex-direction: row;
        box-shadow: none;
        background: transparent;
        padding: 0;
    }
}
.nav-dersler-ok {
    margin-left: auto;
    transition: transform 0.2s;
    transform: rotate(-90deg);
}
.nav-item-acik .nav-dersler-ok {
    transform: rotate(0deg);
}
.nav-submenu-kapali {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.25s ease;
}