/* 语法练习页：偏 Apple 的轻量层次、圆角、毛玻璃与系统字体 */

.grammar-page.grammar-surface {
    --grammar-ink: #1d1d1f;
    --grammar-ink-soft: #6e6e73;
    --grammar-line: rgba(0, 0, 0, 0.06);
    --grammar-accent: #b45309;
    --grammar-accent-fill: #d97706;
    --grammar-blue: #0071e3;
    --grammar-radius-lg: 22px;
    --grammar-radius-md: 14px;
    --grammar-radius-sm: 10px;
    --grammar-shadow-elevated:
        0 0 0 0.5px rgba(0, 0, 0, 0.04),
        0 2px 8px rgba(0, 0, 0, 0.04),
        0 16px 40px rgba(0, 0, 0, 0.08);
    --grammar-shadow-soft: 0 1px 2px rgba(0, 0, 0, 0.05);
    font-family:
        -apple-system,
        BlinkMacSystemFont,
        'SF Pro Text',
        'SF Pro Display',
        'PingFang SC',
        'Hiragino Sans GB',
        'Microsoft YaHei',
        'Helvetica Neue',
        sans-serif;
    background: #ffffff;
    color: var(--grammar-ink);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body.grammar-body-host {
    background-color: #ffffff;
}

.grammar-card {
    border-radius: var(--grammar-radius-lg);
    background: rgba(255, 255, 255, 0.78);
    border: 1px solid rgba(255, 255, 255, 0.65);
    box-shadow: var(--grammar-shadow-elevated);
    -webkit-backdrop-filter: saturate(180%) blur(24px);
    backdrop-filter: saturate(180%) blur(24px);
}

.grammar-card--ghost {
    box-shadow: var(--grammar-shadow-soft);
    background: rgba(255, 255, 255, 0.55);
}

.grammar-card--main {
    /* padding from HTML */
}

.grammar-disclosure.grammar-card {
    padding: 1.1rem 1.35rem;
}

.grammar-disclosure-summary::-webkit-details-marker {
    display: none;
}

.grammar-tools-panel {
    border-radius: var(--grammar-radius-md);
    padding: 1.1rem 1.25rem;
    background: rgba(255, 251, 235, 0.55);
    border: 1px solid rgba(251, 191, 36, 0.22);
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.6);
}

/* 与顶栏主列对齐：单列流式布局 */
.grammar-page-shell {
    display: flex;
    flex-direction: column;
    align-items: stretch;
    min-width: 0;
}

.grammar-shell-stack {
    width: 100%;
    min-width: 0;
}

.grammar-topics-section {
    min-width: 0;
}

.grammar-level-hints-line {
    margin: 0;
    white-space: nowrap;
    overflow-x: auto;
    max-width: 100%;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: thin;
}

.grammar-level-hints-sep {
    display: inline-block;
    padding: 0 0.35em;
    color: #d4d4d4;
    font-weight: 300;
    user-select: none;
}

.grammar-level-card {
    border-radius: var(--grammar-radius-md);
    border: 1px solid var(--grammar-line);
    padding: 1rem 1.1rem;
    background: rgba(255, 255, 255, 0.65);
    box-shadow: var(--grammar-shadow-soft);
}

.grammar-level-tag {
    font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
    font-weight: 600;
    letter-spacing: 0.06em;
    font-size: 0.72rem;
    color: var(--grammar-accent);
}

/* 难度：胶囊多选 */
.grammar-level-pill {
    position: relative;
    cursor: pointer;
    user-select: none;
}

.grammar-level-pill-ui {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 3.5rem;
    padding: 0.45rem 1.05rem;
    border-radius: 9999px;
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--grammar-ink-soft);
    background: rgba(255, 255, 255, 0.85);
    border: 1px solid var(--grammar-line);
    box-shadow: 0 1px 1px rgba(0, 0, 0, 0.03);
}

.grammar-level-pill:has(.grammar-lv-cb:checked) .grammar-level-pill-ui {
    color: var(--grammar-ink);
    background: #fef3c7;
    border-color: rgba(217, 119, 6, 0.45);
    box-shadow: none;
}

.grammar-level-pill .grammar-lv-cb:focus,
.grammar-level-pill .grammar-lv-cb:focus-visible {
    outline: none;
    box-shadow: none;
}

.grammar-input-num {
    border-radius: var(--grammar-radius-sm);
    border: 1px solid var(--grammar-line);
    background: rgba(255, 255, 255, 0.95);
    padding: 0.45rem 0.65rem;
    font-size: 0.875rem;
    font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
    color: var(--grammar-ink);
    box-shadow: inset 0 1px 2px rgba(0, 0, 0, 0.04);
    transition:
        border-color 0.15s ease,
        box-shadow 0.15s ease;
}

.grammar-input-num:focus {
    outline: none;
    border-color: rgba(0, 113, 227, 0.45);
    box-shadow: 0 0 0 3px rgba(0, 113, 227, 0.15);
}

.grammar-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.35rem;
    padding: 0.55rem 1.1rem;
    border-radius: 9999px;
    font-size: 0.875rem;
    font-weight: 600;
    border: 1px solid #d4d4d4;
    cursor: pointer;
    color: var(--grammar-ink);
    background: #e5e5e5;
    box-shadow: none;
    -webkit-tap-highlight-color: transparent;
}

.grammar-btn--primary,
.grammar-btn--primary:hover,
.grammar-btn--primary:active {
    color: var(--grammar-ink);
    background: #e5e5e5;
    border-color: #d4d4d4;
    filter: none;
    box-shadow: none;
}

.grammar-btn--secondary,
.grammar-btn--secondary:hover,
.grammar-btn--secondary:active {
    color: var(--grammar-ink);
    background: #e5e5e5;
    border-color: #d4d4d4;
    box-shadow: none;
}

.grammar-btn--solid,
.grammar-btn--solid:hover:not(:disabled),
.grammar-btn--solid:active:not(:disabled) {
    color: var(--grammar-ink);
    background: #e5e5e5;
    border-color: #d4d4d4;
    filter: none;
    box-shadow: none;
}

.grammar-btn--solid:disabled {
    opacity: 0.38;
    cursor: not-allowed;
}

.grammar-btn--destructive,
.grammar-btn--destructive:hover,
.grammar-btn--destructive:active {
    color: #b91c1c;
    background: #e5e5e5;
    border-color: #d4d4d4;
}

.grammar-btn-text {
    border: none;
    background: #e5e5e5;
    color: var(--grammar-ink);
    cursor: pointer;
    padding: 0.35rem 0.55rem;
    border-radius: 9999px;
    font-size: 0.875rem;
    font-weight: 600;
}

.grammar-btn-text:hover,
.grammar-btn-text:active {
    background: #e5e5e5;
    color: var(--grammar-ink);
}

.grammar-btn-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 2.25rem;
    height: 2.25rem;
    border: none;
    border-radius: 9999px;
    background: #e5e5e5;
    color: var(--grammar-ink);
    cursor: pointer;
}

.grammar-btn-icon:hover,
.grammar-btn-icon:active {
    background: #e5e5e5;
    color: var(--grammar-ink);
}

.grammar-btn:focus-visible,
.grammar-btn-text:focus-visible,
.grammar-btn-icon:focus-visible {
    outline: 2px solid rgba(0, 113, 227, 0.35);
    outline-offset: 2px;
}

.grammar-select {
    border-radius: var(--grammar-radius-sm);
    border: 1px solid var(--grammar-line);
    background: rgba(255, 255, 255, 0.95);
    padding: 0.35rem 0.65rem;
    font-size: 0.8125rem;
    color: var(--grammar-ink);
}

.grammar-status-banner {
    margin-top: 1rem;
    padding: 0.65rem 1rem;
    border-radius: var(--grammar-radius-md);
    font-size: 0.8125rem;
    line-height: 1.5;
}

.grammar-status-banner--info {
    color: var(--grammar-ink-soft);
    background: rgba(255, 255, 255, 0.75);
    border: 1px solid var(--grammar-line);
    box-shadow: var(--grammar-shadow-soft);
}

.grammar-status-banner--error {
    color: #991b1b;
    background: rgba(254, 242, 242, 0.95);
    border: 1px solid rgba(248, 113, 113, 0.35);
}

.grammar-table-shell {
    background: transparent;
    border: none;
    box-shadow: none;
    overflow-x: visible;
}

/* 窄屏不依赖横向滚动：固定布局 + 知识点列换行；数字列与操作列固定宽度，余下给首列 */
.grammar-topic-table--responsive {
    width: 100%;
    table-layout: fixed;
}

.grammar-topic-table--responsive .grammar-th-stat,
.grammar-topic-table--responsive .grammar-td-stat {
    width: 2rem;
    min-width: 2rem;
    max-width: 2.35rem;
    box-sizing: border-box;
}

.grammar-topic-table--responsive .grammar-th-op {
    width: 2.6rem;
    min-width: 2.6rem;
    max-width: 2.85rem;
}

@media (min-width: 480px) {
    .grammar-topic-table--responsive .grammar-th-stat,
    .grammar-topic-table--responsive .grammar-td-stat {
        width: 1.85rem;
        min-width: 1.85rem;
        max-width: 2.35rem;
    }

    .grammar-topic-table--responsive .grammar-th-op {
        width: 2.75rem;
        min-width: 2.75rem;
        max-width: 3rem;
    }
}

@media (min-width: 640px) {
    .grammar-topic-table--responsive .grammar-th-stat,
    .grammar-topic-table--responsive .grammar-td-stat {
        width: 2.25rem;
        min-width: 2.25rem;
        max-width: 2.75rem;
    }

    .grammar-topic-table--responsive .grammar-th-op {
        width: 3.25rem;
        min-width: 3.25rem;
        max-width: 3.5rem;
    }
}

.grammar-topic-table--responsive .grammar-td-l0,
.grammar-topic-table--responsive .grammar-td-l1,
.grammar-topic-table--responsive .grammar-td-l2,
.grammar-topic-table--responsive .grammar-td-l3 {
    min-width: 0;
    overflow-wrap: anywhere;
    word-break: break-word;
    hyphens: auto;
}

.grammar-topic-table--responsive .grammar-td-stat {
    white-space: nowrap;
}

.grammar-table-head th {
    font-weight: 600;
    letter-spacing: 0.08em;
}

.grammar-topic-table td,
.grammar-topic-table th {
    border-bottom: 1px solid rgba(0, 0, 0, 0.04);
    vertical-align: middle;
}

.grammar-topic-table tbody tr {
    transition: background 0.15s ease;
}

.grammar-topic-row-root,
.grammar-topic-row-l1,
.grammar-topic-row-l2,
.grammar-topic-row-l3 {
    background: transparent !important;
}

.grammar-topic-title-root {
    font-size: 1.0625rem;
}

.grammar-topic-title-l1 {
    font-size: 1rem;
}

.grammar-topic-title-l2,
.grammar-topic-name-leaf {
    font-size: 0.98rem;
}

@media (min-width: 640px) {
    .grammar-topic-title-root {
        font-size: 1.125rem;
    }

    .grammar-topic-title-l1 {
        font-size: 1.0625rem;
    }

    .grammar-topic-title-l2,
    .grammar-topic-name-leaf {
        font-size: 1.02rem;
    }
}

/* 操作列展开箭头：无底色，仅保留圆形点击区域 */
.grammar-icon-btn {
    border-radius: 9999px !important;
    background: transparent !important;
    color: var(--grammar-ink) !important;
}

.grammar-icon-btn:hover,
.grammar-icon-btn:active {
    background: transparent !important;
    color: var(--grammar-ink) !important;
}

.grammar-stem-card {
    border-radius: var(--grammar-radius-md);
    border: 1px solid var(--grammar-line);
    background: rgba(255, 255, 255, 0.92);
    padding: 1.25rem 1.35rem;
    box-shadow: var(--grammar-shadow-soft);
}

.grammar-option {
    display: block;
    width: 100%;
    text-align: left;
    border-radius: var(--grammar-radius-md);
    border: 1px solid var(--grammar-line);
    padding: 1.1rem 1.2rem;
    background: #e5e5e5;
    cursor: pointer;
    box-shadow: none;
}

.grammar-option:hover:not(:disabled),
.grammar-option:active:not(:disabled) {
    border-color: var(--grammar-line);
    background: #e5e5e5;
    box-shadow: none;
}

.grammar-option:disabled {
    cursor: default;
    opacity: 0.96;
}

.grammar-option--correct {
    border-color: rgba(34, 197, 94, 0.55);
    background: rgba(240, 253, 244, 0.95);
    box-shadow: 0 0 0 1px rgba(34, 197, 94, 0.12);
}

.grammar-option--wrong {
    border-color: rgba(248, 113, 113, 0.55);
    background: rgba(254, 242, 242, 0.95);
    box-shadow: 0 0 0 1px rgba(248, 113, 113, 0.12);
}

.grammar-option--correct:hover:not(:disabled),
.grammar-option--correct:active:not(:disabled) {
    border-color: rgba(34, 197, 94, 0.55);
    background: rgba(240, 253, 244, 0.95);
    box-shadow: 0 0 0 1px rgba(34, 197, 94, 0.12);
}

.grammar-option--wrong:hover:not(:disabled),
.grammar-option--wrong:active:not(:disabled) {
    border-color: rgba(248, 113, 113, 0.55);
    background: rgba(254, 242, 242, 0.95);
    box-shadow: 0 0 0 1px rgba(248, 113, 113, 0.12);
}

.grammar-stem {
    font-size: 1.125rem;
    line-height: 1.65;
    color: var(--grammar-ink);
}

@media (min-width: 640px) {
    .grammar-stem {
        font-size: 1.1875rem;
        line-height: 1.68;
    }
}

.grammar-stem .grammar-q-level {
    display: inline;
    font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
    font-weight: 700;
    font-size: 0.9em;
    letter-spacing: 0.03em;
    color: var(--grammar-accent);
    margin-right: 0.15em;
}

.grammar-stem .grammar-q-body {
    display: inline;
}

.grammar-blank {
    display: inline-block;
    min-width: 2.5rem;
    padding: 0 0.2em;
    border-bottom: 2px solid rgba(217, 119, 6, 0.55);
    font-weight: 600;
    color: var(--grammar-accent);
}

.grammar-explain-panel {
    border-radius: var(--grammar-radius-md);
    border: 1px solid var(--grammar-line);
    background: rgba(250, 250, 250, 0.9);
    padding: 1.1rem 1.25rem;
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.8);
}

/* 模态：毛玻璃遮罩 + 大圆角卡片 */
.grammar-modal-backdrop {
    display: none;
    align-items: flex-end;
    justify-content: center;
    -webkit-backdrop-filter: blur(18px);
    backdrop-filter: blur(18px);
    background: rgba(0, 0, 0, 0.36);
}

@media (min-width: 640px) {
    .grammar-modal-backdrop {
        align-items: center;
    }
}

#grammar-knowledge-modal.grammar-knowledge-modal--open,
#grammar-export-modal.grammar-export-modal--open,
#grammar-done-modal.grammar-done-modal--open,
#grammar-quiz-modal.grammar-quiz-modal--open {
    display: flex;
}

.grammar-modal-sheet {
    width: 100%;
    overflow: hidden;
    border-radius: var(--grammar-radius-lg);
    background: rgba(255, 255, 255, 0.94);
    border: 1px solid rgba(255, 255, 255, 0.7);
    box-shadow:
        0 0 0 0.5px rgba(0, 0, 0, 0.05),
        0 24px 80px rgba(0, 0, 0, 0.22);
    -webkit-backdrop-filter: saturate(180%) blur(20px);
    backdrop-filter: saturate(180%) blur(20px);
}

#grammar-knowledge-modal {
    display: none;
}

#grammar-export-modal {
    display: none;
}

#grammar-done-modal {
    display: none;
}

#grammar-quiz-modal {
    display: none;
}

/* 列表类模态右上角关闭（×）：灰圆、无悬停变色 */
.grammar-modal-ok-btn {
    display: inline-flex;
    flex-shrink: 0;
    align-items: center;
    justify-content: center;
    width: 2.25rem;
    height: 2.25rem;
    padding: 0;
    border: none;
    border-radius: 9999px;
    background: #e5e5e5;
    color: #1d1d1f;
    font-size: 0.9375rem;
    font-weight: 600;
    line-height: 1;
    cursor: pointer;
    -webkit-tap-highlight-color: transparent;
}

.grammar-modal-ok-btn i {
    display: block;
    line-height: 1;
}

.grammar-modal-ok-btn:hover,
.grammar-modal-ok-btn:active {
    background: #e5e5e5;
    color: #1d1d1f;
}

.grammar-modal-ok-btn:focus-visible {
    background: #e5e5e5;
    color: #1d1d1f;
    outline: 2px solid rgba(0, 113, 227, 0.35);
    outline-offset: 2px;
}

.grammar-quiz-modal__sheet {
    display: flex;
    flex-direction: column;
}

.grammar-topic-name {
    cursor: pointer;
    color: var(--grammar-ink);
}

.grammar-topic-name:hover {
    color: var(--grammar-ink);
}

tr.grammar-topic-actions[hidden] {
    display: none;
}

.grammar-action-row {
    background: rgba(249, 250, 251, 0.92) !important;
}

.grammar-action-row .grammar-action-td {
    padding-right: 0.5rem;
}

@media (min-width: 640px) {
    .grammar-action-row .grammar-action-td {
        padding-right: 0.75rem;
    }
}

/* 与首列 pl-0：全部 / 一级范围 */
.grammar-action-row .grammar-action-td--depth-0,
.grammar-action-row .grammar-action-td--depth-1 {
    padding-left: 0;
}

/* 与 .grammar-td-l2：pl-4 sm:pl-6 */
.grammar-action-row .grammar-action-td--depth-2 {
    padding-left: 1rem;
}

@media (min-width: 640px) {
    .grammar-action-row .grammar-action-td--depth-2 {
        padding-left: 1.5rem;
    }
}

/* 与 .grammar-td-l3：pl-6 sm:pl-10 */
.grammar-action-row .grammar-action-td--depth-3 {
    padding-left: 1.5rem;
}

@media (min-width: 640px) {
    .grammar-action-row .grammar-action-td--depth-3 {
        padding-left: 2.5rem;
    }
}

.grammar-action-row .grammar-action-btns {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

@media (max-width: 480px) {
    .grammar-action-row .grammar-action-btn {
        padding: 0.3rem 0.5rem;
        font-size: 0.6875rem;
        gap: 0.25rem;
    }
}

.grammar-action-row .grammar-action-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.3rem;
    border-radius: 9999px;
    border: 1px solid #d4d4d4;
    padding: 0.35rem 0.65rem;
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--grammar-ink);
    background: #e5e5e5;
    cursor: pointer;
    box-shadow: none;
}

.grammar-action-row .grammar-action-btn:hover,
.grammar-action-row .grammar-action-btn:active {
    border-color: #d4d4d4;
    background: #e5e5e5;
    color: var(--grammar-ink);
}

.grammar-action-row .grammar-action-primary {
    border-color: #d4d4d4;
    color: var(--grammar-ink);
    background: #e5e5e5;
}

.grammar-action-row .grammar-action-primary:hover,
.grammar-action-row .grammar-action-primary:active {
    border-color: #d4d4d4;
    color: var(--grammar-ink);
    background: #e5e5e5;
}

.grammar-knowledge-body .gk-path {
    margin-bottom: 1rem;
    border-bottom: 1px solid rgba(251, 191, 36, 0.35);
    padding-bottom: 0.75rem;
    font-size: 0.8125rem;
    font-weight: 600;
    color: var(--grammar-accent);
    line-height: 1.5;
}

.grammar-knowledge-body .gk-section-title {
    margin-top: 1.25rem;
    margin-bottom: 0.5rem;
    padding-bottom: 0.35rem;
    border-bottom: 2px solid rgba(217, 119, 6, 0.45);
    font-size: 1.0625rem;
    font-weight: 800;
    color: var(--grammar-accent);
    letter-spacing: 0.02em;
}

.grammar-knowledge-body .gk-section-title:first-of-type {
    margin-top: 0;
}

.grammar-knowledge-body .gk-item-title {
    margin-top: 0.75rem;
    margin-bottom: 0.25rem;
    font-size: 0.9375rem;
    font-weight: 800;
    color: #92400e;
}

.grammar-knowledge-body .gk-item-text {
    margin-bottom: 0.75rem;
    font-size: 0.875rem;
    line-height: 1.65;
    color: #404040;
}

.grammar-knowledge-body .gk-fallback {
    font-size: 0.75rem;
    line-height: 1.6;
    color: #525252;
    white-space: pre-wrap;
    font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

.grammar-explain-inner .ge-verdict {
    margin-bottom: 0.75rem;
    font-size: 1rem;
    font-weight: 600;
    color: var(--grammar-ink);
}

.grammar-explain-inner .ge-label {
    margin-bottom: 0.35rem;
    font-size: 0.9375rem;
    font-weight: 800;
    color: var(--grammar-accent);
    letter-spacing: 0.02em;
}

.grammar-explain-inner .ge-main {
    margin-bottom: 0.75rem;
    font-size: 1.02rem;
    line-height: 1.68;
    color: #262626;
}

.grammar-explain-inner .ge-easy-label {
    margin-top: 0.5rem;
    margin-bottom: 0.25rem;
    font-size: 0.875rem;
    font-weight: 800;
    color: #b45309;
}

.grammar-explain-inner .ge-easy-text {
    margin-bottom: 1rem;
    font-size: 1rem;
    line-height: 1.68;
    color: #404040;
}

.grammar-explain-inner .ge-opt {
    margin-bottom: 0.65rem;
    font-size: 0.9375rem;
    line-height: 1.62;
    color: #333;
}

.grammar-explain-inner .ge-opt-key {
    font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
    font-weight: 600;
    color: var(--grammar-accent);
}

/* 与同级 .grammar-topic-title-* / .grammar-topic-name-leaf 字号、字重一致 */
.grammar-td-l0 .grammar-tree-prefix {
    margin-right: 0.15em;
    color: #86868b;
    font-size: 1.0625rem;
    font-weight: 600;
    line-height: 1.35;
}

.grammar-td-l1 .grammar-tree-prefix {
    margin-right: 0.15em;
    color: #86868b;
    font-size: 1rem;
    font-weight: 500;
    line-height: 1.35;
}

.grammar-td-l2 .grammar-tree-prefix {
    margin-right: 0.15em;
    color: #86868b;
    font-size: 0.98rem;
    font-weight: 500;
    line-height: 1.35;
}

.grammar-td-l3 .grammar-tree-prefix {
    margin-right: 0.15em;
    color: #86868b;
    font-size: 0.98rem;
    font-weight: 500;
    line-height: 1.35;
}

@media (min-width: 640px) {
    .grammar-td-l0 .grammar-tree-prefix {
        font-size: 1.125rem;
    }

    .grammar-td-l1 .grammar-tree-prefix {
        font-size: 1.0625rem;
    }

    .grammar-td-l2 .grammar-tree-prefix,
    .grammar-td-l3 .grammar-tree-prefix {
        font-size: 1.02rem;
    }
}

.grammar-td-l0 {
    font-weight: 700;
}

.grammar-topic-title-root:focus-visible,
.grammar-topic-title-l1:focus-visible,
.grammar-topic-title-l2:focus-visible {
    outline: 2px solid rgba(0, 113, 227, 0.45);
    outline-offset: 3px;
    border-radius: 4px;
}

.grammar-td-l1 {
    font-weight: 600;
}

.grammar-td-l2 {
    font-weight: 500;
}

.grammar-stat-ok {
    color: #15803d !important;
    font-weight: 700;
}

.grammar-stat-err {
    color: #b91c1c !important;
    font-weight: 700;
}

.grammar-stat-rem {
    color: #86868b !important;
    font-weight: 600;
}

.grammar-tree-toggle,
.grammar-leaf-toggle {
    cursor: pointer;
    border: none;
    padding: 0;
    line-height: 1;
}

.grammar-done-table tbody tr {
    transition: background 0.12s ease;
}