/* From Generative AI to Agent - vis-network-tutorial layout
 * =========================================================
 * Wide (>= 860px): chain graph + definitions on the left, exercise panel on the right.
 * Narrow (< 860px): title, graph, definitions, and exercise stacked.
 * The whole page always fits inside the iframe height (CANVAS_HEIGHT + 2);
 * the graph area absorbs any spare height so nothing scrolls.
 *
 * Colors are from the Okabe-Ito color-blind-safe palette (blue / orange),
 * and every answered link also carries a check or X glyph and a text status.
 */

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html, body {
    height: 100%;
    overflow: hidden;
}

body {
    font-family: Arial, Helvetica, sans-serif;
    background-color: aliceblue;
    color: #1a1a1a;
    font-size: 16px;
}

.container {
    display: flex;
    flex-direction: column;
    width: 100%;
    height: 100vh;
    padding: 6px 10px 4px 10px;
    gap: 6px;
}

/* ===========================================
   TITLE (Top Center)
   =========================================== */
.title-bar {
    text-align: center;
    flex: 0 0 auto;
}

.title {
    font-size: 20px;
    font-weight: bold;
}

.subtitle {
    font-size: 16px;
    color: #333;
    margin-top: 2px;
}

/* ===========================================
   TWO-COLUMN LAYOUT
   =========================================== */
.layout {
    flex: 1 1 auto;
    min-height: 0;
    display: flex;
    gap: 10px;
}

.left-col {
    flex: 1 1 auto;
    min-width: 0;
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.graph-wrap {
    position: relative;
    flex: 1 1 auto;
    min-height: 130px;
    background-color: white;
    border: 1px solid #c9d6e3;
    border-radius: 8px;
    overflow: hidden;
}

#network {
    width: 100%;
    height: 100%;
}

/* Legend: upper left of the graph (wide layout only) */
.legend {
    position: absolute;
    top: 6px;
    left: 8px;
    font-size: 14px;
    color: #333;
    background-color: rgba(255, 255, 255, 0.92);
    padding: 3px 6px;
    border-radius: 6px;
    z-index: 10;
}

.lg {
    display: inline-block;
    font-weight: bold;
    padding: 0 4px;
    border-radius: 4px;
    margin-left: 6px;
}

.lg:first-child { margin-left: 0; }
.lg-open    { color: #555; border: 2px dashed #888; }
.lg-current { color: #003f73; border: 2px solid #0072b2; }
.lg-correct { color: #fff; background: #0072b2; }
.lg-wrong   { color: #8a3c00; background: #fdf0e1; border: 2px dashed #d55e00; }

/* ===========================================
   EXPLORATION PANEL (node definitions)
   =========================================== */
.explore-panel {
    flex: 0 0 auto;
    background-color: rgba(255, 255, 255, 0.95);
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    padding: 6px 10px;
}

.chain-list {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 3px;
    font-size: 14px;
}

.chain-label {
    font-weight: bold;
    margin-right: 2px;
}

.arrow {
    color: #555;
}

.node-btn {
    font-size: 14px;
    padding: 3px 7px;
    border: 2px solid #0072b2;
    border-radius: 6px;
    background: #eef6fc;
    color: #003f73;
    cursor: pointer;
}

.node-btn:hover { background: #d6eaf8; }
.node-btn[aria-pressed="true"] {
    background: #0072b2;
    color: white;
}

.definition {
    margin-top: 5px;
    font-size: 15px;
    line-height: 1.35;
    min-height: 2.7em;
}

.definition strong { color: #003f73; }

/* ===========================================
   RIGHT PANEL (Exercise)
   =========================================== */
.right-panel {
    flex: 0 0 380px;
    display: flex;
    flex-direction: column;
    gap: 6px;
    background-color: rgba(255, 255, 255, 0.95);
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    padding: 8px 10px;
    min-height: 0;
}

.link-header {
    font-size: 16px;
    line-height: 1.3;
}

.link-step {
    font-weight: bold;
    color: #003f73;
    margin-right: 4px;
}

.link-nodes {
    font-weight: bold;
}

.question {
    font-size: 16px;
    font-style: italic;
}

.options {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.option {
    display: flex;
    align-items: flex-start;
    gap: 6px;
    font-size: 15px;
    line-height: 1.3;
    padding: 4px 7px;
    border: 2px solid #b8c7d6;
    border-radius: 6px;
    background: #fbfdff;
    cursor: pointer;
}

.option input {
    margin-top: 3px;
    flex: 0 0 auto;
    width: 16px;
    height: 16px;
    cursor: pointer;
}

.option:hover { border-color: #0072b2; }
.option:focus-within { outline: 3px solid #56b4e9; outline-offset: 1px; }
.option.selected { border-color: #0072b2; background: #eef6fc; }

.option.locked { cursor: default; }
.option.locked:hover { border-color: #b8c7d6; }
.option.locked input { cursor: default; }

/* After commit: the correct option and a wrong choice are marked by glyph + text, not color only */
.option.is-correct {
    border-color: #0072b2;
    background: #e3f1fb;
}
.option.is-wrong {
    border-color: #d55e00;
    background: #fdf0e1;
    border-style: dashed;
}

.tag {
    display: inline-block;
    font-size: 14px;
    font-weight: bold;
    margin-left: 4px;
    white-space: nowrap;
}
.tag-correct { color: #003f73; }
.tag-wrong   { color: #8a3c00; }

.feedback {
    font-size: 15px;
    line-height: 1.35;
    min-height: 0;
}

.feedback:empty { display: none; }

.feedback .fb {
    padding: 5px 8px;
    border-radius: 6px;
    border-left: 5px solid #0072b2;
    background: #eef6fc;
}

.feedback .fb.fb-wrong {
    border-left-color: #d55e00;
    background: #fdf0e1;
}

.feedback .fb-final {
    margin-top: 4px;
    font-weight: bold;
}

/* ===========================================
   CONTROL BUTTONS
   =========================================== */
.controls {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    align-items: center;
    margin-top: auto;
}

.btn {
    padding: 7px 14px;
    font-size: 15px;
    font-weight: bold;
    border: none;
    border-radius: 6px;
    cursor: pointer;
}

.btn:focus-visible, .node-btn:focus-visible { outline: 3px solid #56b4e9; outline-offset: 2px; }

.btn-primary { background-color: #0072b2; color: white; }
.btn-primary:hover { background-color: #005a8c; }
.btn-primary:disabled { background-color: #9cc3dd; cursor: not-allowed; }

.btn-secondary { background-color: #616161; color: white; }
.btn-secondary:hover { background-color: #4a4a4a; }

.score {
    font-size: 15px;
    font-weight: bold;
    margin-left: auto;
}

.back-link {
    flex: 0 0 auto;
    font-size: 14px;
    color: #005a8c;
}

/* ===========================================
   RESPONSIVE: stack below 860px
   =========================================== */
@media (max-width: 859px) {
    .container { padding: 4px 6px 2px 6px; gap: 4px; }
    .title { font-size: 18px; }
    .subtitle { font-size: 15px; }
    .layout { flex-direction: column; gap: 4px; }
    .left-col { flex: 1 1 auto; min-height: 0; gap: 4px; }
    .right-panel { flex: 0 0 auto; padding: 6px 8px; gap: 4px; }
    .legend { display: none; }
    .explore-panel { padding: 5px 8px; }
    .node-btn { padding: 2px 6px; }
    .definition { font-size: 14px; }
    .option { font-size: 14px; padding: 3px 6px; }
    .link-header, .question { font-size: 15px; }
    .feedback { font-size: 14px; }
    .btn { padding: 6px 11px; font-size: 14px; }
    .score { font-size: 14px; }
}

/* xAPI teaching panel (?xapi=teaching): pin the layout to its production height and let the page scroll. */
html:has(.xapi-panel), body:has(.xapi-panel) { height: auto; overflow: auto; }
body:has(.xapi-panel) .container { height: 760px; }