:root {
    --bg: #f4f6f8;
    --surface: #ffffff;
    --surface-muted: #eef2f6;
    --text: #17202a;
    --muted: #697586;
    --line: #d9e0e7;
    --primary: #0f766e;
    --primary-strong: #115e59;
    --accent: #2563eb;
    --shadow: 0 18px 42px rgba(17, 24, 39, 0.12);
    --sidebar-width: 280px;
}

* {
    box-sizing: border-box;
}

[hidden] {
    display: none !important;
}

html {
    min-height: 100%;
}

body {
    min-height: 100vh;
    margin: 0;
    background: var(--bg);
    color: var(--text);
    font-family: Arial, Helvetica, sans-serif;
    letter-spacing: 0;
}

a {
    color: inherit;
}

.app-shell {
    display: grid;
    grid-template-columns: var(--sidebar-width) minmax(0, 1fr);
    min-height: 100vh;
}

body.sidebar-collapsed .app-shell {
    grid-template-columns: 0 minmax(0, 1fr);
}

body.sidebar-collapsed .sidebar {
    width: 0;
    padding: 0;
    overflow: hidden;
    border-right: 0;
}

body.sidebar-collapsed.sidebar-expanded .app-shell {
    grid-template-columns: var(--sidebar-width) minmax(0, 1fr);
}

body.sidebar-collapsed.sidebar-expanded .sidebar {
    width: auto;
    padding: 20px 16px;
    overflow: auto;
    border-right: 1px solid rgba(255, 255, 255, 0.08);
}

.sidebar {
    position: sticky;
    top: 0;
    height: 100vh;
    min-height: 100vh;
    padding: 20px 16px;
    background: #111827;
    color: #f8fafc;
    border-right: 1px solid rgba(255, 255, 255, 0.08);
    overflow-y: auto;
}

.brand {
    display: flex;
    align-items: center;
    gap: 12px;
    min-height: 48px;
    margin-bottom: 28px;
}

.brand-mark {
    display: grid;
    place-items: center;
    width: 44px;
    height: 44px;
    border-radius: 8px;
    background: var(--primary);
    color: #ffffff;
    font-size: 14px;
    font-weight: 800;
}

.brand strong,
.brand small {
    display: block;
}

.brand strong {
    font-size: 18px;
}

.brand small {
    margin-top: 2px;
    color: #b6c2d1;
    font-size: 12px;
}

.nav-list {
    display: grid;
    gap: 22px;
}

.nav-section {
    display: grid;
    gap: 6px;
}

.nav-heading {
    padding: 0 12px 6px;
    color: #91a0b4;
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.nav-link {
    display: flex;
    align-items: center;
    gap: 10px;
    min-height: 42px;
    padding: 10px 12px;
    border-radius: 8px;
    color: #d6deea;
    text-decoration: none;
    font-size: 15px;
}

.nav-link:hover,
.nav-link.active {
    background: rgba(255, 255, 255, 0.1);
    color: #ffffff;
}

.nav-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: currentColor;
}

.main-area {
    min-width: 0;
}

.topbar {
    position: sticky;
    top: 0;
    z-index: 20;
    display: flex;
    align-items: center;
    gap: 16px;
    min-height: 76px;
    padding: 16px 28px;
    background: rgba(255, 255, 255, 0.94);
    border-bottom: 1px solid var(--line);
    backdrop-filter: blur(12px);
}

.notification-menu {
    position: relative;
    margin-left: auto;
}

.notification-menu summary {
    position: relative;
    display: grid;
    place-items: center;
    width: 42px;
    height: 42px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: #ffffff;
    cursor: pointer;
    list-style: none;
}

.notification-menu summary::-webkit-details-marker {
    display: none;
}

.bell-icon {
    width: 16px;
    height: 16px;
    border: 2px solid var(--text);
    border-radius: 10px 10px 5px 5px;
    border-bottom-width: 3px;
}

.notification-menu summary strong {
    position: absolute;
    top: -7px;
    right: -7px;
    min-width: 20px;
    height: 20px;
    padding: 2px 5px;
    border-radius: 999px;
    background: #dc2626;
    color: #ffffff;
    font-size: 11px;
    line-height: 16px;
    text-align: center;
}

.notification-panel {
    position: absolute;
    top: calc(100% + 10px);
    right: 0;
    z-index: 50;
    width: min(380px, calc(100vw - 24px));
    max-height: 460px;
    overflow: auto;
    padding: 14px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: #ffffff;
    box-shadow: var(--shadow);
}

.notification-panel header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
    margin-bottom: 10px;
}

.notification-panel h2,
.notification-panel p {
    margin: 0;
}

.notification-panel h2 {
    font-size: 16px;
}

.notification-panel button {
    border: 0;
    background: transparent;
    color: var(--primary-strong);
    cursor: pointer;
    font: inherit;
    font-weight: 700;
}

.notification-list {
    display: grid;
    gap: 8px;
}

.notification-item button {
    display: grid;
    width: 100%;
    gap: 4px;
    padding: 10px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: #ffffff;
    color: var(--text);
    text-align: left;
}

.notification-item.unread button {
    border-color: rgba(15, 118, 110, 0.45);
    background: #ecfdf5;
}

.notification-item small {
    color: var(--muted);
}

.actions button {
    border: 1px solid var(--line);
    border-radius: 8px;
    background: #ffffff;
    color: var(--text);
    cursor: pointer;
    font: inherit;
}

.topbar h1,
.topbar p {
    margin: 0;
}

.topbar h1 {
    font-size: 24px;
    line-height: 1.2;
}

.topbar-kicker {
    margin-bottom: 2px;
    color: var(--muted);
    font-size: 13px;
}

.content {
    width: 100%;
    margin: 0;
    padding: 28px;
}

.empty-state {
    display: grid;
    justify-items: center;
    align-content: center;
    min-height: calc(100vh - 132px);
    padding: 32px;
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: 8px;
    text-align: center;
}

.empty-icon {
    display: grid;
    place-items: center;
    width: 72px;
    height: 72px;
    margin-bottom: 18px;
    border-radius: 8px;
    background: var(--surface-muted);
    color: var(--primary-strong);
    font-size: 15px;
    font-weight: 800;
}

.empty-state h2 {
    max-width: 760px;
    margin: 0 0 10px;
    font-size: clamp(22px, 4vw, 32px);
    line-height: 1.2;
}

.empty-state p {
    max-width: 660px;
    margin: 0;
    color: var(--muted);
    font-size: 16px;
    line-height: 1.6;
}

.button-link {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 42px;
    margin-top: 20px;
    padding: 10px 16px;
    border-radius: 8px;
    background: var(--primary);
    color: #ffffff;
    font-weight: 700;
    text-decoration: none;
}

.primary-button,
.secondary-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 42px;
    padding: 10px 16px;
    border: 0;
    border-radius: 8px;
    font-weight: 700;
    text-decoration: none;
    cursor: pointer;
}

.primary-button {
    background: var(--primary);
    color: #ffffff;
}

.secondary-button {
    background: var(--surface-muted);
    color: var(--text);
}