/* 
    # Copyright (c) 2026 Deni Hamdani
    # SPDX-License-Identifier: MIT

    ============================================
    App Layout Grid
    ============================================ 
*/

body {
    display: grid;
    grid-template-columns: var(--w-sidebar) 1fr;
    grid-template-rows: var(--h-header) 1fr var(--h-status);
    height: 100vh;
    overflow: hidden;
}

#app-header {
    grid-column: 1 / -1;
    grid-row: 1;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 var(--space-4);
    background: var(--bg-base);
    border-bottom: 1px solid var(--border-default);
    z-index: 10;
}

#sidebar {
    grid-column: 1;
    grid-row: 2;
    display: flex;
    flex-direction: column;
    background: var(--bg-surface);
    border-right: 1px solid var(--border-default);
    overflow: hidden;
}

#main-content {
    grid-column: 2;
    grid-row: 2;
    display: flex;
    flex-direction: column;
    gap: var(--space-4);
    padding: var(--space-4);
    overflow: hidden;
}

#status-bar {
    grid-column: 1 / -1;
    grid-row: 3;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 var(--space-4);
    background: var(--bg-surface);
    border-top: 1px solid var(--border-default);
    font-size: var(--fs-caption);
    color: var(--text-tertiary);
}

/* Panels: Merge takes 60%, Preview takes 40% */
.merge-panel {
    flex: 3;
    min-height: 0;
}

.preview-panel {
    flex: 2;
    min-height: 0;
}

/* Responsive */
@media (min-width: 1920px) {
    :root {
        --w-sidebar: 300px;
    }
}

@media (max-width: 1280px) {
    :root {
        --w-sidebar: 240px;
    }
}

@media (max-width: 1024px) {
    :root {
        --w-sidebar: 220px;
    }

    #main-content {
        gap: var(--space-2);
        padding: var(--space-2);
    }
}

/* ═══════════════════════════════════════════════════
   RESPONSIVE: TABLET (768–1023px)
   ═══════════════════════════════════════════════════ */

@media (min-width: 768px) and (max-width: 1023px) {
    body {
        grid-template-columns: 1fr;
    }

    #sidebar {
        position: fixed;
        left: 0;
        top: var(--h-header);
        bottom: 0;
        width: 280px;
        transform: translateX(-100%);
        transition: transform var(--t-normal);
        z-index: 200;
        box-shadow: none;
    }

    #sidebar.drawer-open {
        transform: translateX(0);
        box-shadow: var(--shadow-lg);
    }

    #main-content {
        grid-column: 1 / -1;
    }

    .merge-panel {
        flex: 55;
    }

    .preview-panel {
        flex: 45;
    }

    .drawer-toggle {
        display: inline-flex;
    }

    .drawer-backdrop {
        position: fixed;
        inset: 0;
        top: var(--h-header);
        background: var(--bg-overlay);
        z-index: 199;
    }
}

/* ═══════════════════════════════════════════════════
   RESPONSIVE: MOBILE (<768px)
   ═══════════════════════════════════════════════════ */

@media (max-width: 767px) {

    html,
    body {
        height: 100vh;
        height: 100dvh;
    }

    body {
        display: flex;
        flex-direction: column;
    }

    #app-header {
        flex: 0 0 auto;
        height: calc(var(--h-header) + var(--safe-top));
        padding-top: var(--safe-top);
    }

    #sidebar {
        display: none;
        flex: 1;
        min-height: 0;
        width: 100%;
        overflow-y: auto;
        border-right: none;
        position: static;
        transform: none;
        transition: none;
        box-shadow: none;
    }

    #main-content {
        display: none;
        flex: 1;
        min-height: 0;
        overflow: hidden;
    }

    #status-bar {
        display: none;
    }

    .drawer-toggle {
        display: none;
    }

    .drawer-backdrop {
        display: none !important;
    }

    /* ── Tab Visibility ── */
    body.tab-items #sidebar {
        display: flex;
    }

    body.tab-merge #main-content {
        display: flex;
    }

    body.tab-preview #main-content {
        display: flex;
    }

    body.tab-merge .preview-panel {
        display: none;
    }

    body.tab-merge .merge-panel {
        flex: 1;
    }

    body.tab-preview .merge-panel {
        display: none;
    }

    body.tab-preview .preview-panel {
        flex: 1;
    }
}