/* ============================================================
   RESET & BASE
   ============================================================ */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}
html { scroll-behavior: smooth; }
body {
    font-family: var(--f-body);
    color: var(--txt);
    background: var(--bg-page);
    line-height: 1.7;
    font-size: 17px;
}

/* ============================================================
   LAYOUT
   ============================================================ */
.app {
    display: flex;
    min-height: 100vh;
}

.main {
    margin-left: var(--sidebar-w);
    flex: 1;
    min-height: 100vh;
    background: var(--bg-page);
}

/* ============================================================
   SECTIONS
   ============================================================ */
.section {
    display: none;
    padding: 48px 40px 64px;
    max-width: 1200px;
    margin: 0 auto;
}
.section.active {
    display: block;
    animation: fadeIn 0.3s ease;
}
@media (max-width: 800px) {
    .section { padding: 24px 16px 48px; }
}
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(8px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ============================================================
   MOBILE HEADER
   ============================================================ */
.mobile-header {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 150;
    background: var(--bg-sidebar);
    padding: 12px 16px;
    align-items: center;
    gap: 12px;
}
.mobile-header .hamburger {
    background: none;
    border: none;
    color: #e2e8f0;
    font-size: 20px;
    cursor: pointer;
    padding: 4px;
}
.mobile-header .m-brand {
    font-family: var(--f-brand);
    color: var(--accent);
    font-size: 16px;
}
.mobile-ers-link {
    margin-left: auto;
    color: #fff;
    background: var(--accent);
    border-radius: 999px;
    padding: 5px 13px;
    font-family: var(--f-head);
    font-size: 12px;
    font-weight: 700;
    text-decoration: none;
}
.overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
    z-index: 190;
}
.overlay.show { display: block; }

@media (max-width: 800px) {
    .sidebar {
        transform: translateX(-100%);
        transition: transform 0.3s ease;
    }
    .sidebar.open { transform: translateX(0); }
    .main {
        margin-left: 0;
        padding-top: 52px;
    }
    .mobile-header { display: flex; }
}