.app-shell {
    display: grid;
    grid-template-columns: 258px 1fr;
    grid-template-rows: 64px 1fr;
    grid-template-areas:
        "topbar topbar"
        "sidebar main";
    min-height: 100vh;
    background:
        linear-gradient(180deg, rgba(255, 255, 255, 0.015), transparent 160px),
        transparent;
}

.topbar {
    grid-area: topbar;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 var(--space-6);
    border-bottom: 1px solid var(--brand-border);
    background: rgba(36, 34, 36, 0.88);
    backdrop-filter: blur(12px);
    position: sticky;
    top: 0;
    z-index: 40;
}

.topbar__brand {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    font-weight: 750;
    letter-spacing: 0.04em;
    font-size: 1rem;
}

.topbar__brand img {
    border-radius: 8px;
    box-shadow: 0 0 0 1px var(--brand-border-strong);
}

.topbar__brand .dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--brand-orange);
}

.topbar__right {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    color: var(--brand-fg-muted);
    font-size: 0.9rem;
}

.sidebar {
    grid-area: sidebar;
    border-right: 1px solid var(--brand-border);
    background:
        linear-gradient(180deg, rgba(255, 255, 255, 0.025), transparent 160px),
        rgba(36, 34, 36, 0.72);
    padding: var(--space-5) var(--space-3);
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
}

.sidebar a.nav-item {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: 11px 14px;
    border-radius: 12px;
    border: 1px solid transparent;
    color: var(--brand-fg-muted);
    font-weight: 620;
    text-decoration: none;
    transition: background 0.15s, border-color 0.15s, color 0.15s, transform 0.15s;
}

.sidebar a.nav-item:hover {
    background: rgba(255, 255, 255, 0.04);
    border-color: var(--brand-border);
    color: var(--brand-fg);
    text-decoration: none;
    transform: translateX(2px);
}

.sidebar a.nav-item.active {
    background:
        linear-gradient(90deg, var(--brand-orange-soft), rgba(222, 95, 59, 0.05));
    border-color: rgba(222, 95, 59, 0.36);
    color: #ffd2c5;
    box-shadow: inset 3px 0 0 var(--brand-orange);
}

.sidebar a.nav-item .icon {
    width: 16px;
    height: 16px;
    flex-shrink: 0;
}

.main {
    grid-area: main;
    padding: var(--space-6) clamp(20px, 4vw, 58px);
    overflow-y: auto;
}

.auth-shell {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-5);
    background:
        linear-gradient(135deg, rgba(222, 95, 59, 0.17), transparent 32%),
        linear-gradient(315deg, rgba(168, 64, 40, 0.12), transparent 40%),
        var(--brand-bg-deep);
}

.auth-card {
    background:
        linear-gradient(180deg, rgba(255, 255, 255, 0.045), transparent),
        rgba(43, 41, 43, 0.92);
    border: 1px solid var(--brand-border-strong);
    border-radius: 22px;
    padding: var(--space-7);
    width: 100%;
    max-width: 420px;
    box-shadow: var(--shadow-card);
}

.grid {
    display: grid;
    gap: var(--space-4);
}

.grid--cards {
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
}

.grid--two {
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

@media (max-width: 900px) {
    .app-shell {
        grid-template-columns: 1fr;
        grid-template-rows: 64px auto 1fr;
        grid-template-areas:
            "topbar"
            "sidebar"
            "main";
    }

    .sidebar {
        flex-direction: row;
        overflow-x: auto;
        padding: var(--space-2);
        gap: var(--space-2);
    }

    .sidebar a.nav-item {
        white-space: nowrap;
        padding: var(--space-2) var(--space-3);
    }

    .main {
        padding: var(--space-4);
    }

    .topbar {
        padding: 0 var(--space-4);
    }
}