:root {
            --bg: var(--teach-bg-mid);
            --panel: var(--teach-paper);
            --text: var(--teach-ink-900);
            --muted: var(--teach-ink-500);
            --accent: var(--teach-primary);
            --accent-strong: var(--teach-primary-2);
            --border: var(--teach-border);
            --step-bg: #f3f7f9;
            --step-border: var(--teach-border);
        }
        body {
            margin: 0;
            font-family: var(--teach-font);
            background: var(--teach-bg);
            color: var(--text);
            min-height: 100vh;
        }
        .wrap {
            width: min(1700px, 97vw);
            margin: 12px auto;
        }
        .panel {
            background: var(--panel);
            border: 1px solid var(--border);
            border-radius: var(--teach-radius-lg);
            box-shadow: var(--teach-shadow);
            padding: 22px;
        }
        h1 {
            font-size: clamp(1.7rem, 2.6vw, 2.4rem);
            margin: 0 0 8px;
            letter-spacing: 0.01em;
        }
        .toolbar {
            display: grid;
            grid-template-columns: repeat(2, minmax(320px, 1fr));
            gap: 12px;
            align-items: start;
        }
        .step {
            background: var(--step-bg);
            border: 1px solid var(--step-border);
            border-radius: var(--teach-radius-md);
            padding: 10px;
        }
        .step-head {
            display: flex;
            align-items: center;
            justify-content: space-between;
            gap: 8px;
            margin-bottom: 6px;
        }
        .step-tools {
            display: flex;
            gap: 6px;
        }
        .tiny-btn {
            width: auto;
            border-radius: var(--teach-radius-sm);
            border: 1px solid var(--border);
            background: #fff;
            color: var(--teach-ink-700);
            box-shadow: none;
            font-size: 0.78rem;
            font-weight: 700;
            padding: 4px 8px;
        }
        .step-submit {
            display: flex;
            align-items: stretch;
            justify-content: stretch;
            background: transparent;
            border: none;
            padding: 0;
        }
        .checklist {
            max-height: 260px;
            overflow: auto;
            border: 1px solid var(--border);
            border-radius: var(--teach-radius-md);
            background: #fff;
            padding: 6px;
        }
        .check-item {
            display: block;
            margin: 0;
            padding: 6px 8px;
            border-radius: 8px;
            font-weight: 600;
            color: var(--text);
            font-size: 0.92rem;
        }
        .check-item:hover {
            background: var(--step-bg);
        }
        .check-item input {
            width: auto;
            margin-right: 8px;
            vertical-align: middle;
            transform: translateY(-1px);
        }
        .search {
            margin-bottom: 6px;
            font-size: 0.95rem;
        }
        label {
            display: block;
            font-size: 0.95rem;
            color: var(--muted);
            margin-bottom: 5px;
            font-weight: 700;
        }
        select, input, button {
            width: 100%;
            border-radius: 10px;
            border: 1px solid var(--border);
            padding: 10px 11px;
            font-size: 1.02rem;
            background: #fff;
            color: var(--text);
        }
        select:focus, input:focus {
            outline: 2px solid rgba(15, 118, 110, 0.35);
            border-color: var(--accent);
        }
        button {
            width: auto;
            cursor: pointer;
            background: var(--accent);
            color: #fff;
            border: none;
            font-weight: 600;
            padding: 11px 16px;
            font-size: 1rem;
            box-shadow: 0 8px 14px rgba(15, 118, 110, 0.28);
        }
        button:hover {
            background: var(--accent-strong);
        }
        .meta {
            margin: 8px 0 0;
            color: var(--muted);
            font-size: 0.98rem;
            line-height: 1.4;
        }
        .helper {
            margin: 0 0 12px;
            color: var(--muted);
            font-size: 0.94rem;
        }
        .actions {
            display: flex;
            gap: 10px;
            margin-top: 10px;
            flex-wrap: wrap;
        }
        .btn-secondary {
            background: var(--teach-accent);
        }
        .btn-ghost {
            background: #fff;
            color: var(--text);
            border: 1px solid var(--border);
            box-shadow: none;
        }
        .error {
            margin-top: 12px;
            color: var(--teach-danger);
            font-weight: 600;
            font-size: 1rem;
            background: #fff1f0;
            border: 1px solid #f4c9c4;
            border-radius: var(--teach-radius-md);
            padding: 8px 10px;
        }
        .vocab-panel {
            margin-top: 10px;
            border: 1px solid var(--border);
            border-radius: var(--teach-radius-lg);
            padding: 12px;
            background: var(--step-bg);
        }
        .vocab-panel.hidden {
            display: none;
        }
        .vocab-panel h2 {
            margin: 0 0 10px;
            font-size: 1.2rem;
            color: var(--accent);
        }
        .vocab-bank {
            display: flex;
            flex-wrap: wrap;
            gap: 8px;
        }
        .vocab-chip {
            display: inline-block;
            padding: 6px 10px;
            border-radius: var(--teach-radius-md);
            background: #eaf8ff;
            color: var(--accent);
            font-size: 0.95rem;
            border: 1px solid var(--border);
        }
        .vocab-chip .tr {
            color: var(--teach-success);
            margin-left: 6px;
            font-weight: 600;
        }
        .generated-slot {
            font-weight: 900;
        }
        .vocab-chip .missing {
            color: var(--teach-danger);
            margin-left: 6px;
            font-weight: 600;
        }
        ol {
            margin: 14px 0 0;
            padding-left: 34px;
        }
        li {
            margin: 7px 0;
            line-height: 1.45;
            font-size: clamp(1.2rem, 1.9vw, 1.9rem);
            padding: 7px 9px;
            border-radius: var(--teach-radius-md);
            outline: none;
        }
        li.focused {
            background: #eaf8ff;
            border: 2px solid var(--accent);
            box-shadow: 0 0 0 4px rgba(15, 126, 168, 0.18);
        }
        .sentence-text {
            display: block;
        }
        body.presentation .wrap {
            width: 100vw;
            margin: 0;
        }
        body.presentation .panel {
            border-radius: 0;
            min-height: 100vh;
            border: none;
            box-shadow: none;
            padding: 24px 36px;
        }
        body.presentation h1,
        body.presentation .toolbar,
        body.presentation .meta,
        body.presentation .actions,
        body.presentation .vocab-panel {
            display: none;
        }
        body.presentation ol {
            margin: 0;
            padding-left: 56px;
        }
        body.presentation li {
            font-size: clamp(2rem, 3vw, 3.2rem);
            margin: 18px 0;
            padding: 14px 16px;
        }
        body.presentation li.focused {
            box-shadow: 0 0 0 6px rgba(15, 126, 168, 0.24);
        }
        @media (max-width: 760px) {
            .toolbar {
                grid-template-columns: 1fr;
            }
            button {
                width: 100%;
            }
        }