/* ============================================================
   Layout System & Responsive Breakpoints
   ============================================================ */

/* Main App Grid */
.app {
    display: grid;
    grid-template-rows: var(--header-height) 1fr var(--status-bar-height);
    grid-template-columns: var(--sidebar-width) 1fr;
    grid-template-areas:
        "header  header"
        "sidebar main"
        "status  status";
    height: 100vh;
    width: 100vw;
    overflow: hidden;
}

.app-header {
    grid-area: header;
    display: flex;
    align-items: center;
    padding: 0 var(--space-4);
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-default);
    gap: var(--space-3);
    z-index: var(--z-sticky);
}

.app-sidebar {
    grid-area: sidebar;
    display: flex;
    flex-direction: column;
    background: var(--bg-secondary);
    border-right: 1px solid var(--border-default);
    overflow: hidden;
}

.app-main {
    grid-area: main;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    background: var(--bg-primary);
}

.app-status {
    grid-area: status;
    display: flex;
    align-items: center;
    padding: 0 var(--space-4);
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-default);
    font-size: var(--text-xs);
    color: var(--text-secondary);
    gap: var(--space-4);
}

/* Content Containers */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-4);
}

.content-area {
    flex: 1;
    overflow-y: auto;
    overflow-x: hidden;
}

/* Flex Utilities */
.flex {
    display: flex;
}

.flex-col {
    flex-direction: column;
}

.flex-wrap {
    flex-wrap: wrap;
}

.flex-1 {
    flex: 1;
}

.flex-center {
    display: flex;
    align-items: center;
    justify-content: center;
}

.flex-between {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.items-center {
    align-items: center;
}

.items-start {
    align-items: flex-start;
}

.items-end {
    align-items: flex-end;
}

.justify-center {
    justify-content: center;
}

.justify-between {
    justify-content: space-between;
}

.justify-end {
    justify-content: flex-end;
}

.gap-1 {
    gap: var(--space-1);
}

.gap-2 {
    gap: var(--space-2);
}

.gap-3 {
    gap: var(--space-3);
}

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

/* Button Base */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: var(--space-2) var(--space-4);
    border-radius: var(--radius-md);
    font-size: var(--text-sm);
    font-weight: var(--weight-medium);
    line-height: 1;
    white-space: nowrap;
    transition: all var(--duration-fast) var(--ease-default);
    height: var(--input-height);
    min-width: 0;
}

.btn-primary {
    background: var(--accent-gradient);
    color: white;
    box-shadow: var(--shadow-sm);
}

.btn-primary:hover:not(:disabled) {
    filter: brightness(1.1);
    box-shadow: var(--shadow-md), var(--shadow-glow);
    transform: translateY(-1px);
}

.btn-primary:active:not(:disabled) {
    transform: translateY(0);
}

.btn-secondary {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border-default);
}

.btn-secondary:hover:not(:disabled) {
    background: var(--bg-hover);
    border-color: var(--border-default);
}

.btn-danger {
    background: var(--error);
    color: white;
}

.btn-danger:hover:not(:disabled) {
    filter: brightness(1.1);
}

.btn-ghost {
    color: var(--text-secondary);
    padding: var(--space-1) var(--space-2);
    height: auto;
}

.btn-ghost:hover {
    color: var(--text-primary);
    background: var(--bg-hover);
}

.btn-sm {
    height: 32px;
    padding: var(--space-1) var(--space-3);
    font-size: var(--text-xs);
}

.btn-icon {
    width: 36px;
    height: 36px;
    padding: 0;
    border-radius: var(--radius-md);
}

/* Badge */
.badge {
    display: inline-flex;
    align-items: center;
    padding: 2px var(--space-2);
    border-radius: var(--radius-full);
    font-size: var(--text-xs);
    font-weight: var(--weight-medium);
    line-height: 1.4;
}

.badge-online {
    background: var(--success-bg);
    color: var(--success);
}

.badge-busy {
    background: var(--warning-bg);
    color: var(--warning);
}

.badge-offline {
    background: var(--error-bg);
    color: var(--error);
}

.badge-info {
    background: var(--info-bg);
    color: var(--info);
}

/* Status Dot */
.status-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    display: inline-block;
    flex-shrink: 0;
}

.status-dot.online {
    background: var(--status-online);
}

.status-dot.busy {
    background: var(--status-busy);
    animation: pulse 2s infinite;
}

.status-dot.offline {
    background: var(--status-offline);
}

.status-dot.connecting {
    background: var(--status-connecting);
    animation: pulse 1s infinite;
}

/* Connection Banner */
.connection-banner {
    display: none;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: var(--space-2) var(--space-4);
    font-size: var(--text-sm);
    font-weight: var(--weight-medium);
    z-index: var(--z-banner);
}

.connection-banner.reconnecting {
    display: flex;
    background: var(--warning-bg);
    color: var(--warning);
    border-bottom: 1px solid var(--warning);
}

.connection-banner.offline {
    display: flex;
    background: var(--error-bg);
    color: var(--error);
    border-bottom: 1px solid var(--error);
}

/* Spinner */
.spinner {
    width: 16px;
    height: 16px;
    border: 2px solid var(--border-default);
    border-top-color: var(--accent-primary);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

.spinner-lg {
    width: 32px;
    height: 32px;
    border-width: 3px;
}

/* Responsive */
@media (max-width: 768px) {
    .app {
        grid-template-columns: 1fr;
        grid-template-areas:
            "header"
            "main"
            "status";
    }

    .app-sidebar {
        position: fixed;
        top: var(--header-height);
        left: 0;
        bottom: var(--status-bar-height);
        width: var(--sidebar-width);
        z-index: var(--z-modal);
        transform: translateX(-100%);
        transition: transform var(--duration-normal) var(--ease-default);
    }

    .app-sidebar.open {
        transform: translateX(0);
        box-shadow: var(--shadow-xl);
    }

    .sidebar-overlay {
        display: none;
        position: fixed;
        inset: 0;
        background: rgba(0, 0, 0, 0.5);
        z-index: calc(var(--z-modal) - 1);
    }

    .sidebar-overlay.open {
        display: block;
    }
}

/* Tablet */
@media (min-width: 769px) and (max-width: 1024px) {
    :root {
        --sidebar-width: 240px;
    }
}

/* Hidden utilities */
.hidden {
    display: none !important;
}

.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
}

/* Text utilities */
.text-sm {
    font-size: var(--text-sm);
}

.text-xs {
    font-size: var(--text-xs);
}

.text-secondary {
    color: var(--text-secondary);
}

.text-center {
    text-align: center;
}

.truncate {
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

/* Spacing utilities */
.mt-2 {
    margin-top: var(--space-2);
}

.mt-4 {
    margin-top: var(--space-4);
}

.mb-2 {
    margin-bottom: var(--space-2);
}

.mb-4 {
    margin-bottom: var(--space-4);
}

.p-2 {
    padding: var(--space-2);
}

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