/* Main two-panel application layout. */



.app-layout {
    display: grid;
    grid-template-columns: minmax(260px, 1fr) 8px minmax(320px, var(--lesson-width, 50vw));
    height: 100vh;
    min-height: 100vh;
}

.app-layout.lessons-hidden {
    grid-template-columns: 1fr;
}

.app-layout.lessons-hidden .lesson-area {
    display: none;
}

.app-layout.lessons-hidden .resize-handle {
    display: none;
}

.resize-handle {
    width: 8px;
    border: 0;
    border-left: 1px solid var(--line);
    border-right: 1px solid var(--line);
    background: #e7e7e2;
    cursor: col-resize;
}

.resize-handle:hover,
.resize-handle:focus-visible,
.resize-handle.is-resizing {
    background: var(--accent-light);
    outline: 2px solid var(--accent);
    outline-offset: -2px;
}

.show-lessons-button {
    display: none;
    position: fixed;
    top: 14px;
    right: 84px;
    z-index: 20;
    border: 1px solid var(--accent);
    border-radius: 6px;
    padding: 9px 13px;
    background: var(--accent);
    color: #ffffff;
    box-shadow: var(--shadow-soft);
}

.app-layout.lessons-hidden ~ .show-lessons-button {
    display: block;
}

.app-layout.lessons-hidden .preview-header {
    padding-right: 74px;
}

.preview-area {
    padding: 12px;
    min-height: 0;
    overflow-y: auto;
}

.preview-header {
    position: relative;
    display: flex;
    z-index: 2;
    align-items: flex-end;
    min-width: 0;
    padding: 0 10px;
    margin-bottom: -1px;
}

.preview-header[hidden] {
    display: none;
}