/* Shared fixes also apply when the lesson is opened on a smaller device. */
.step[type="button"] {
    border: 1px solid transparent;
    background: transparent;
    cursor: pointer;
    font: inherit;
    padding: 6px;
    min-height: 44px;
    border-radius: 10px;
    text-align: left;
}
.step[type="button"]:hover, .step[type="button"].active {
    background: #eaf7f0;
    border-color: #76c893;
}
.puzzle-board, .blank-card, .teaching-reference-bill-wrapper {
    aspect-ratio: var(--bill-ratio, 2.1 / 1);
}
.puzzle-board { background-size: contain; }
.puzzle-drop-zone img, .puzzle-drag-item img, .element-img,
.teaching-reference-bill-img, #payment-video { object-fit: contain; }
.bill-img { height: auto; }
.bank-money, .counter-money { touch-action: manipulation; }

/* Activated only when both dimensions leave room for a classroom workspace. */
html.classroom-mode { font-size: clamp(16px, 1.15vw, 30px); }
.classroom-enabled .page-container {
    width: 100%;
    max-width: none;
    height: 100vh;
    height: 100dvh;
    max-height: none;
    padding: 12px 16px 30px;
    border-radius: 0;
    box-shadow: none;
}
.classroom-enabled .classroom-shell {
    display: grid;
    grid-template-columns: clamp(196px, 15vw, 320px) minmax(0, 1fr) clamp(104px, 8.5vw, 180px);
    grid-template-rows: minmax(0, 1fr);
    gap: 16px;
    min-height: 0;
    min-width: 0;
    height: 100%;
}
.classroom-enabled .page-container.classroom-shell { height: 100vh; height: 100dvh; }
.classroom-enabled #practice-view.classroom-shell,
.classroom-enabled #price-setting-view.classroom-shell { display: grid; }
.classroom-enabled .classroom-bottom-actions {
    grid-template-columns: clamp(196px, 15vw, 320px) minmax(0, 1fr);
    grid-template-rows: minmax(0, 1fr) auto;
}
.classroom-enabled .classroom-sidebar {
    grid-column: 1;
    grid-row: 1 / -1;
    display: flex;
    flex-direction: column;
    gap: 10px;
    min-width: 0;
    min-height: 0;
    padding-right: 8px;
    border-right: 1px solid #dce8f4;
    overflow-y: auto;
    overscroll-behavior: contain;
}
.classroom-enabled .classroom-sidebar > * { flex-shrink: 0; }
.classroom-enabled .main-title {
    font-size: 1.25rem;
    text-align: left;
    line-height: 1.35;
    margin: 0;
    padding: 4px 0;
}
.classroom-enabled .toolbar { margin: 0; gap: 3px; flex-wrap: wrap; }
.classroom-enabled .toolbar-btn { width: 44px; height: 44px; font-size: 16px; box-shadow: none; }
.classroom-enabled .toolbar #prev-btn, .classroom-enabled .toolbar #next-btn { display: none; }
.classroom-enabled .view-mode-toggle { margin: 0; gap: 0; padding: 0; }
.classroom-enabled .view-mode-btn { min-width: 44px; min-height: 44px; padding: 4px; }
.classroom-enabled .classroom-sidebar .navbar {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 6px;
    margin: 0;
}
.classroom-enabled .classroom-sidebar .nav-item {
    display: flex;
    align-items: center;
    justify-content: center;
    white-space: normal;
    text-align: center;
    min-height: 44px;
    padding: 6px;
    font-size: 1rem;
    border: 1px solid #dce8f4;
    border-radius: 12px;
}
.classroom-enabled #level-navbar, .classroom-enabled #step-navbar,
.classroom-enabled #category-navbar, .classroom-enabled #price-preset-navbar {
    grid-template-columns: 1fr;
}
.classroom-enabled .mode-switch, .classroom-enabled .pay-mode-bar {
    display: grid;
    grid-template-columns: 1fr 1fr;
    margin: 0;
    gap: 6px;
}
.classroom-enabled .mode-btn { min-height: 44px; padding: 6px; font-size: 1rem; border-radius: 12px; }
.classroom-enabled .practice-steps-container { margin: 0; }
.classroom-enabled .steps { flex-direction: column; gap: 5px; margin: 0; }
.classroom-enabled .step { margin: 0; width: 100%; min-height: 44px; }
.classroom-enabled .step-circle { flex: 0 0 30px; }
.classroom-enabled .step-label { font-size: 1rem; }
.classroom-enabled .classroom-sidebar footer { margin-top: auto; padding-top: 8px; }
.classroom-enabled #practice-view .classroom-sidebar footer,
.classroom-enabled #price-setting-view .classroom-sidebar footer { margin-top: auto; }
.classroom-enabled .classroom-sidebar .end-btn {
    width: 100%;
    min-height: 44px;
    padding: 8px;
    font-size: 1rem;
    border-radius: 12px;
}
.classroom-enabled .classroom-navigation {
    grid-column: 3;
    grid-row: 1;
    display: flex;
    align-items: center;
}
.classroom-enabled .classroom-navigation .unified-navigation {
    width: 100%;
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin: 0;
}
.classroom-enabled .classroom-navigation .nav-btn {
    width: 100%;
    min-height: 52px;
    padding: 10px 6px;
    font-size: 1rem;
    border-radius: 14px;
}
.classroom-enabled .site-filing {
    position: absolute;
    left: 16px;
    right: 16px;
    bottom: 4px;
    width: auto;
    margin: 0;
    padding: 0;
    line-height: 20px;
    font-size: 12px;
}
.classroom-enabled .classroom-shell > .content-card {
    grid-column: 2;
    grid-row: 1;
    min-width: 0;
    min-height: 0;
    margin: 0;
    padding: 12px;
    justify-content: safe center;
    overflow-y: auto;
    border-radius: 16px;
    background: #f8fbfe;
}
.classroom-enabled .classroom-bottom-actions > .unified-navigation {
    grid-column: 2;
    grid-row: 2;
    margin: 0;
    gap: 16px;
}
.classroom-enabled .classroom-bottom-actions > .unified-navigation .nav-btn {
    min-height: 52px;
    min-width: 140px;
    font-size: 1.15rem;
}
.classroom-enabled .classroom-teacher-settings {
    border: 1px solid #c6d8e8;
    border-radius: 12px;
    background: #f5f9fd;
    padding: 4px;
}
.classroom-enabled .classroom-teacher-settings summary {
    cursor: pointer;
    min-height: 44px;
    padding: 10px 4px;
    color: #2c4a7c;
    font-weight: bold;
}
.classroom-enabled .classroom-teacher-settings .nav-btn {
    width: 100%; min-height: 44px; margin: 6px 0; padding: 8px 4px;
    border: 1px solid #c6d8e8; border-radius: 8px;
    background: white; color: #2c4a7c; font-size: .9rem;
}
.classroom-enabled .item-strip { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 6px; margin: 0; }
.classroom-enabled .item-chip, .classroom-enabled .strip-btn {
    min-height: 44px; font-size: .9rem; padding: 6px; justify-content: center;
}
.classroom-enabled .item-chip img { width: 24px; height: 24px; }

/* Currency lessons: both sides remain visible, with space reserved for the text. */
.classroom-enabled .teaching-page { padding: 0; }
.classroom-enabled .teaching-section h2 { margin: 0 0 24px; font-size: 1.6rem; }
.classroom-enabled .bill-display, .classroom-enabled .coin-side-display {
    display: flex;
    flex-direction: row;
    flex-wrap: nowrap;
    justify-content: center;
    align-items: center;
    gap: 24px;
    margin: 0 0 24px;
}
.classroom-enabled .bill-img { width: calc(50% - 12px); max-width: none; max-height: 52vh; object-fit: contain; }
.classroom-enabled .color-info { margin: 0; }
.classroom-enabled .color-badge { margin: 0 0 12px; font-size: 1.35rem; }
.classroom-enabled .color-info p, .classroom-enabled .element-display p,
.classroom-enabled .teaching-section > p { font-size: 1.2rem; color: #2c4a7c; line-height: 1.6; }
.classroom-enabled .coin-side-img { width: min(40%, 44vh); height: auto; }
.classroom-enabled .coin-element-img { width: min(65%, 54vh); height: auto; }
.classroom-enabled .element-display { margin: 0; }
.classroom-enabled .element-img, .classroom-enabled .landscape-img {
    width: min(80%, 650px); height: auto; max-height: 52vh; object-fit: contain;
}
.classroom-enabled .teaching-focus-layout { display: grid; grid-template-columns: 1fr 48px 1.5fr; align-items: center; gap: 20px; }
.classroom-enabled #teaching-page2 .element-img, .classroom-enabled #teaching-page3 .element-img {
    width: auto; max-width: 100%; height: 40vh; max-height: 420px; margin: 0; object-fit: contain;
}
.classroom-enabled .teaching-guide-arrow { transform: rotate(-90deg); margin: 0; }
.classroom-enabled .teaching-reference-bill-wrapper { width: 100%; }
.classroom-enabled .color-select-container, .classroom-enabled .puzzle-container,
.classroom-enabled .coin-practice-layout, .classroom-enabled .completion-container,
.classroom-enabled .coin-completion-container {
    display: grid;
    grid-template-columns: minmax(0, 1.2fr) minmax(0, 1fr);
    gap: 24px;
    align-items: center;
    height: auto;
}
.classroom-enabled .puzzle-board, .classroom-enabled .blank-card { width: 100%; }
.classroom-enabled .puzzle-right, .classroom-enabled .color-select-right, .classroom-enabled .coin-practice-right { width: 100%; }
.classroom-enabled .coin-canvas { width: min(100%, 62vh); }
.classroom-enabled .color-options-grid { gap: 16px; padding: 8px; }
.classroom-enabled .color-circle { width: clamp(60px, 5.2vw, 112px); height: clamp(60px, 5.2vw, 112px); }
.classroom-enabled .puzzle-drag-items { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.classroom-enabled .puzzle-drag-item img { height: clamp(100px, 25vh, 280px); object-fit: contain; }
.classroom-enabled .puzzle-tip, .classroom-enabled .puzzle-success-text { font-size: 1.15rem; }
.classroom-enabled .landscape-grid-large { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.classroom-enabled .landscape-option-item img { height: clamp(100px, 22vh, 250px); }
.classroom-enabled .coin-color-options, .classroom-enabled .coin-image-options.three-up { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.classroom-enabled .coin-shape-options { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.classroom-enabled .shape-preview { width: min(100%, 140px); height: auto; aspect-ratio: 1; }
.classroom-enabled .coin-option-label { font-size: 1rem; }
.classroom-enabled .completion-bill-img { width: 100%; max-height: 33vh; object-fit: contain; }
.classroom-enabled .coin-completion-left { flex-wrap: nowrap; }
.classroom-enabled .coin-completion-img { width: 46%; }

/* Cash workspaces use the whole available height; all denominations fit at once. */
.classroom-enabled .exchange-canvas, .classroom-enabled .cash-canvas {
    display: grid;
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr) minmax(0, 1fr);
    gap: 12px;
    height: 100%;
    min-height: 0;
}
.classroom-enabled .counter-panel, .classroom-enabled .money-counter-panel,
.classroom-enabled .money-bank, .classroom-enabled .good-display { min-width: 0; min-height: 0; padding: 10px; }
.classroom-enabled .money-counter { min-height: 180px; }
.classroom-enabled .money-grid.bills { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.classroom-enabled .money-grid.coins { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.classroom-enabled .money-grid { gap: 8px; }
.classroom-enabled .bank-money img { height: clamp(54px, 11vh, 180px); object-fit: contain; }
.classroom-enabled .bank-money.coin img { height: clamp(44px, 8vh, 130px); }
.classroom-enabled .bank-money.coin.small img { height: clamp(40px, 7vh, 112px); }
.classroom-enabled .bank-money .money-label { font-size: .85rem; }
.classroom-enabled .bank-section h3, .classroom-enabled .counter-title { font-size: 1.1rem; }
.classroom-enabled .result-message { font-size: 1rem; min-height: 52px; }
.classroom-enabled .good-image-wrap { min-height: 0; }
.classroom-enabled #good-image { max-height: 52vh; }
.classroom-enabled .good-switch-row { grid-template-columns: 1fr 1fr; gap: 8px; }
.classroom-enabled .price-tag { grid-column: 1 / -1; grid-row: 1; font-size: 1.6rem; }
.classroom-enabled .good-switch-row .nav-btn {
    min-height: 44px; padding: 8px 4px; border: 1px solid #9eb8db;
    border-radius: 10px; background: white; color: #2c4a7c;
}

/* Electronic payment and shopping retain their own task structure. */
.classroom-enabled .video-canvas { width: 100%; height: 100%; max-height: 78vh; aspect-ratio: auto; }
.classroom-enabled #payment-video { object-fit: contain; background: #101820; }
.classroom-enabled .step-description { width: 100%; font-size: 1.15rem; }
.classroom-enabled .shopping-canvas, .classroom-enabled .split-layout { min-height: 0; height: 100%; max-width: none; }
.classroom-enabled .shopping-canvas > .flow-page.active { height: 100%; }
.classroom-enabled .cashier-wrap { min-height: 0; }
.classroom-enabled .cashier-wrap .money-bank { max-height: none; height: 100%; }
.classroom-enabled .media-panel video { min-height: 0; height: 100%; max-height: 82vh; }
.classroom-enabled .ops-canvas .flow-page { min-height: 0; }
.classroom-enabled #page-2-sim .sim-layout { margin-right: 0; }
.classroom-enabled .sim-layout { grid-template-columns: minmax(240px, 1fr) minmax(0, 1fr); }
.classroom-enabled .pscreen { height: min(58vh, 520px); }
.classroom-enabled .pp { height: 100%; }
.classroom-enabled .sim-right { min-height: 0; align-self: center; }
.classroom-enabled .sim-tip { position: static; transform: none; width: auto; min-height: 52px; margin-top: 12px; }
.classroom-enabled .wchi[data-phone-act] {
    display: inline-flex; align-items: center; justify-content: center; min-width: 44px; min-height: 44px;
}
.classroom-enabled .wni[data-phone-act], .classroom-enabled .plusi[data-phone-act],
.classroom-enabled .apai[data-phone-act] { min-height: 44px; cursor: pointer; }
@media (hover: none) {
    .classroom-enabled button:hover { transform: none; }
}