body { font-family: var(--ui-font); background-color: var(--word-workspace); color: var(--word-text); height: 100vh; display: flex; flex-direction: column; overflow: hidden; transition: background-color 0.3s, color 0.3s; }

        /* --- Word Header (Title Bar + Tabs) --- */
        .word-header { background-color: var(--word-header-bg); flex-shrink: 0; transition: background-color 0.3s; display: flex; flex-direction: column; z-index: 100; position: relative;}
        
        .title-bar { height: 30px; display: flex; justify-content: space-between; align-items: center; padding: 0 10px; font-size: 12px; color: white; }
        .title-bar-left { display: flex; align-items: center; gap: 15px; }
        .title-bar-left svg { fill: white; width: 14px; height: 14px; cursor: pointer; opacity: 0.8; }
        .title-bar-left svg:hover { opacity: 1; }
        .title-bar-center { flex-grow: 1; text-align: center; font-weight: normal; }
        .title-bar-right { display: flex; gap: 10px; }
        .window-controls { display: flex; }
        .window-control { width: 30px; height: 30px; display: flex; justify-content: center; align-items: center; cursor: pointer; }
        .window-control:hover { background-color: rgba(255,255,255,0.1); }
        .window-control.close:hover { background-color: #E81123; }

        .ribbon-tabs { display: flex; padding-left: 10px; gap: 2px; }
        .ribbon-tab {
            padding: 6px 16px; font-size: 13px; cursor: pointer; color: white; border: 1px solid transparent; border-bottom: none; margin-bottom: -1px; z-index: 1;
            transition: background-color 0.2s, color 0.2s; white-space: nowrap;
        }
        .ribbon-tab:hover:not(.active) { background-color: rgba(255,255,255,0.15); }
        .ribbon-tab.active { background-color: var(--word-ribbon-active); color: var(--word-blue); border-color: var(--word-border); border-bottom-color: var(--word-ribbon-active); z-index: 3; position: relative; }

        /* --- Ribbon Content --- */
        .ribbon-content { 
            background-color: var(--word-ribbon-active); 
            border-bottom: 1px solid var(--word-border); 
            padding: 4px 12px 6px 12px; 
            display: flex; 
            flex-wrap: nowrap; 
            align-items: stretch; 
            min-height: 92px; 
            height: 92px; 
            max-height: 92px;
            box-sizing: border-box;
            flex-shrink: 0;
            flex-grow: 0;
            overflow-x: auto;
            overflow-y: hidden; 
            transition: background-color 0.3s, height 0.3s, padding 0.3s; 
            gap: 8px 0; 
            scrollbar-width: none;
            -ms-overflow-style: none;
        }
        .ribbon-content::-webkit-scrollbar { display: none; height: 0; width: 0; }

        /* ====== Thin Ribbon Mode (精簡功能區) ======
           Hides text labels under icons + group titles, shrinks icons & selects so
           the ribbon takes ~50px instead of ~92px on smaller laptop screens. */
        body.ribbon-thin .ribbon-content {
            min-height: 50px;
            height: 50px;
            max-height: 50px;
            padding: 3px 8px 4px 8px;
            gap: 4px 0;
        }
        body.ribbon-thin .ribbon-group {
            height: 44px;
            padding: 0 8px;
            justify-content: center;
        }
        body.ribbon-thin #settingsGroup.ribbon-group {
            height: 44px;
            min-height: 44px;
            padding: 0 6px;
        }
        body.ribbon-thin .ribbon-group-label {
            display: none;
        }
        body.ribbon-thin .ribbon-group-content {
            height: 44px;
            align-items: center;
            gap: 2px;
        }
        body.ribbon-thin #settingsGroup .ribbon-group-content {
            height: 44px;
            min-height: 44px;
        }
        /* Icon-only buttons: hide every direct text label by zeroing font-size, keep SVG */
        body.ribbon-thin .ribbon-btn.large {
            height: 36px;
            min-width: 36px;
            padding: 0 6px;
            padding-top: 0;
            justify-content: center;
            flex-direction: row;
            gap: 0;
            font-size: 0;
        }
        body.ribbon-thin .ribbon-btn.large svg {
            width: 22px !important;
            height: 22px !important;
            margin: 0 !important;
        }
        /* SVG inline <text> (e.g. "20" inside the WPM mark icon) inherits parent font-size; force it back */
        body.ribbon-thin .ribbon-btn.large svg text {
            font-size: 14px;
        }
        body.ribbon-thin .ribbon-wpm-mark-toggle .ribbon-wpm-mark-toggle__lbl {
            display: none;
        }
        body.ribbon-thin .ribbon-timer {
            font-size: 20px;
            padding: 0 8px;
        }
        body.ribbon-thin .exam-mode-lbl {
            font-size: 11px;
            line-height: 1.15;
        }
        /* Compact settings 2-row grid */
        body.ribbon-thin .ribbon-input-group--exam-settings {
            grid-template-columns: 56px 132px 6px 70px 132px;
            row-gap: 2px;
            min-height: 44px;
        }
        body.ribbon-thin .ribbon-input-group--exam-settings .es-lbl {
            font-size: 11px;
        }
        body.ribbon-thin .ribbon-select,
        body.ribbon-thin .wpm-tier-face,
        body.ribbon-thin .ribbon-input-group--exam-settings .es-ctl .ribbon-select,
        body.ribbon-thin .es-topic-inner select,
        body.ribbon-thin .es-topic-inner button {
            height: 22px !important;
            font-size: 11px !important;
            padding-top: 0;
            padding-bottom: 0;
        }
        body.ribbon-thin .dice-btn {
            height: 22px;
            line-height: 22px;
            padding: 0 6px;
        }
        /* Right-tabs thin-mode toggle (icon-only) */
        .ribbon-thin-tab {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            padding: 6px 8px;
            background: transparent;
            border: 1px solid transparent;
            border-bottom: none;
            color: white;
            cursor: pointer;
            transition: background-color 0.2s, color 0.2s;
            line-height: 0;
        }
        .ribbon-thin-tab .ribbon-thin-tab__icon {
            width: 16px;
            height: 16px;
            stroke: currentColor;
            fill: none;
            stroke-width: 2;
            stroke-linecap: round;
            stroke-linejoin: round;
        }
        .ribbon-thin-tab .ribbon-thin-tab__icon--expand { display: none; }
        .ribbon-thin-tab.active .ribbon-thin-tab__icon--compress { display: none; }
        .ribbon-thin-tab.active .ribbon-thin-tab__icon--expand { display: inline-block; }
        .ribbon-thin-tab:hover { background-color: rgba(255,255,255,0.15); }
        .ribbon-thin-tab.active {
            background-color: var(--word-ribbon-active);
            color: var(--word-blue);
            border-color: var(--word-border);
        }

        .ribbon-group { 
            display: flex; 
            flex-direction: column; 
            justify-content: space-between; 
            padding: 0 12px; 
            border-right: 1px solid var(--word-border); 
            height: 78px; 
            flex-shrink: 0;
        }
        #settingsGroup.ribbon-group {
            height: 78px;
            min-height: 78px;
            padding-top: 2px;
            padding-bottom: 2px;
        }
        /* 開發者工具：固定在右側的可收合直向工具列 */
        .dev-tools-float {
            position: fixed;
            z-index: 160;
            display: none;
            flex-direction: column;
            top: 96px;
            right: 0;
            left: auto;
            bottom: 28px;
            width: 60px;
            min-width: 60px;
            max-width: 60px;
            height: auto;
            min-height: 180px;
            max-height: none;
            background: var(--word-page);
            color: var(--word-text);
            border: 1px solid var(--word-border);
            border-right: none;
            border-radius: 8px 0 0 8px;
            box-shadow: 0 10px 36px rgba(0, 0, 0, 0.22);
            overflow: hidden;
            box-sizing: border-box;
            transition: width 0.2s ease, min-width 0.2s ease, max-width 0.2s ease;
        }
        .dev-tools-float.dev-tools-float--collapsed {
            width: 24px;
            min-width: 24px;
            max-width: 24px;
        }
        .dev-tools-float.dev-tools-float--collapsed .dev-tools-float__body {
            display: none;
        }
        .dev-tools-float.dev-tools-float--collapsed .dev-tools-float__close {
            display: none;
        }
        .dev-tools-float.dev-tools-float--collapsed .dev-tools-float__header {
            justify-content: center;
            gap: 0;
            padding: 3px 0;
            border-bottom: none;
        }
        .dev-tools-float__header {
            display: flex;
            align-items: center;
            justify-content: flex-start;
            gap: 2px;
            padding: 4px 2px;
            background: var(--word-ribbon-active);
            border-bottom: 1px solid var(--word-border);
            flex-shrink: 0;
        }
        .dev-tools-float__title {
            display: none;
        }
        .dev-tools-float__toggle,
        .dev-tools-float__close {
            display: flex;
            align-items: center;
            justify-content: center;
            width: 22px;
            height: 24px;
            padding: 0;
            border: 1px solid transparent;
            border-radius: 4px;
            background: transparent;
            color: var(--word-text);
            font-size: 15px;
            line-height: 1;
            cursor: pointer;
            flex-shrink: 0;
        }
        .dev-tools-float__toggle {
            font-size: 13px;
            font-weight: 700;
        }
        .dev-tools-float__toggle-icon { display: inline; }
        .dev-tools-float.dev-tools-float--collapsed .dev-tools-float__toggle {
            width: 20px;
            border-color: var(--word-border);
            background: rgba(43, 87, 154, 0.08);
        }
        body.dark-mode .dev-tools-float.dev-tools-float--collapsed .dev-tools-float__toggle {
            background: rgba(122, 165, 235, 0.12);
        }
        .dev-tools-float__close {
            margin-left: auto;
        }
        .dev-tools-float.dev-tools-float--collapsed .dev-tools-float__toggle { transform: none; }
        .dev-tools-float__toggle:hover,
        .dev-tools-float__close:hover {
            background: rgba(0, 0, 0, 0.06);
            border-color: var(--word-border);
        }
        body.dark-mode .dev-tools-float__toggle:hover,
        body.dark-mode .dev-tools-float__close:hover {
            background: rgba(255, 255, 255, 0.08);
        }
        .dev-tools-float__body {
            display: flex;
            flex-direction: column;
            flex-wrap: nowrap;
            align-items: center;
            align-content: stretch;
            gap: 6px;
            padding: 8px 2px 10px;
            overflow-y: auto;
            overflow-x: hidden;
            flex: 1;
            min-height: 0;
            box-sizing: border-box;
        }
        /* Photoshop-style: every dev tool icon is a uniform 52x52 tile with the label hidden — name + description appear as a hover tooltip only */
        .dev-tools-float .dev-tools-float__body > .ribbon-btn.large.dev-ribbon-btn,
        .dev-tools-float .dev-tools-float__body > .dev-ribbon-panel {
            width: 52px;
            max-width: 52px;
            min-width: 52px;
            height: 52px;
            min-height: 52px;
            max-height: 52px;
            box-sizing: border-box;
            padding: 4px;
            position: relative;
            border: 1px solid transparent;
            border-radius: 4px;
            background: transparent;
            cursor: pointer;
            flex: 0 0 auto;
            outline: none;
            display: flex;
            flex-direction: column;
            justify-content: center;
            align-items: center;
            gap: 0;
        }
        .dev-tools-float .dev-tools-float__body > .ribbon-btn.large.dev-ribbon-btn:hover,
        .dev-tools-float .dev-tools-float__body > .dev-ribbon-panel:hover,
        .dev-tools-float .dev-tools-float__body > .dev-ribbon-panel.dev-ribbon-panel--open {
            background-color: #C6E2FF;
            border-color: #99C9FF;
        }
        body.dark-mode .dev-tools-float .dev-tools-float__body > .ribbon-btn.large.dev-ribbon-btn:hover,
        body.dark-mode .dev-tools-float .dev-tools-float__body > .dev-ribbon-panel:hover,
        body.dark-mode .dev-tools-float .dev-tools-float__body > .dev-ribbon-panel.dev-ribbon-panel--open {
            background-color: #444;
            border-color: #555;
        }
        .dev-tools-float .dev-tools-float__body > .ribbon-btn.large.dev-ribbon-btn > svg {
            margin-bottom: 0;
            flex-shrink: 0;
            width: 26px;
            height: 26px;
        }
        /* Hide every inline label inside the dev tool box — Photoshop-style */
        .dev-tools-float .dev-tools-float__body > .ribbon-btn.large.dev-ribbon-btn span {
            display: none;
        }
        .dev-tools-float .dev-ribbon-panel {
            display: flex !important;
            grid-template-columns: none;
            grid-template-rows: none;
        }
        .dev-tools-float .dev-ribbon-panel > svg.dev-ribbon-panel__glyph {
            width: 26px;
            height: 26px;
            grid-column: auto;
            grid-row: auto;
            place-self: auto;
            margin: 0;
        }
        /* Photoshop-style "options" flyout: rendered to <body> via JS so it never gets clipped by .dev-tools-float overflow */
        .dev-ribbon-panel__flyout {
            display: flex;
            flex-direction: column;
            gap: 8px;
        }
        /* Inline (collapsed) state — flyout content is hidden inside the icon; JS will move it to body when opened */
        .dev-tools-float .dev-ribbon-panel > .dev-ribbon-panel__flyout:not(.dev-ribbon-panel__flyout--portal) {
            display: none;
        }
        .dev-ribbon-panel__flyout--portal {
            position: fixed;
            min-width: 220px;
            max-width: 260px;
            padding: 10px 12px 12px;
            background: var(--word-page);
            color: var(--word-text);
            border: 1px solid var(--word-border);
            border-radius: 4px;
            box-shadow: 0 10px 28px rgba(0, 0, 0, 0.24);
            z-index: 9999;
            box-sizing: border-box;
        }
        .dev-ribbon-panel__caption {
            font-size: 12px;
            font-weight: 600;
            color: var(--word-text);
            text-align: left;
            line-height: 1.3;
            grid-column: auto;
            grid-row: auto;
            align-self: auto;
            padding: 0;
        }
        .dev-ribbon-panel__flyout--portal .dev-ribbon-panel__controls {
            display: flex;
            flex-direction: row;
            align-items: center;
            gap: 8px;
            width: 100%;
        }
        .dev-ribbon-panel__flyout--portal .dev-ribbon-panel__controls input[type="range"] {
            flex: 1 1 auto;
            height: 18px;
        }
        .dev-ribbon-panel__flyout--portal .dev-ribbon-panel__controls .dev-auto-err-pct {
            min-width: 38px;
            text-align: right;
            font-size: 12px;
            font-variant-numeric: tabular-nums;
            font-weight: 600;
        }
        .dev-ribbon-panel__flyout--portal .dev-ribbon-panel__controls .ribbon-select {
            width: 100%;
            height: 28px;
            font-size: 12px;
        }
        /* Photoshop-style hover tooltip rendered to <body> via JS so it never clips */
        .dev-tip-portal {
            position: fixed;
            top: 0;
            left: 0;
            display: none;
            background: #2b2b2b;
            color: #ffffff;
            padding: 6px 9px;
            border-radius: 4px;
            font-size: 11px;
            font-weight: 500;
            line-height: 1.35;
            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.25);
            z-index: 10000;
            pointer-events: none;
            max-width: 240px;
            white-space: normal;
            text-align: left;
        }
        .dev-tip-portal__name { font-weight: 700; display: block; }
        .dev-tip-portal__desc { display: block; opacity: 0.85; margin-top: 2px; font-weight: 400; }
        @media (max-width: 900px) {
            .dev-tools-float {
                top: 72px;
                bottom: 28px;
            }
        }
        @media (max-width: 600px) {
            .dev-tools-float {
                top: 64px;
                bottom: 24px;
            }
        }

        .ribbon-group:first-child { padding-left: 0; }
        .ribbon-group:last-child { border-right: none; padding-right: 0; }

        .ribbon-group-content {
            display: flex;
            flex-direction: row;
            align-items: flex-start;
            gap: 6px;
            height: 58px; 
        }
        #settingsGroup .ribbon-group-content {
            height: auto;
            min-height: 58px;
            align-items: center;
        }

        .ribbon-group-label { 
            width: 100%; 
            text-align: center; 
            font-size: 11px; 
            color: var(--word-text-light); 
            line-height: 1.2; 
            padding-top: 3px;
            padding-bottom: 2px;
            white-space: nowrap;
        }
        
        .ribbon-btn {
            display: flex; flex-direction: column; align-items: center; justify-content: center; background: transparent; border: 1px solid transparent; cursor: pointer; padding: 4px 6px; border-radius: 4px; color: var(--word-text); font-size: 12px; gap: 4px; min-width: 50px; transition: background 0.1s; white-space: nowrap;
        }
        .ribbon-btn:hover:not(:disabled) { background-color: #C6E2FF; border-color: #99C9FF; }
        body.dark-mode .ribbon-btn:hover:not(:disabled) { background-color: #444; border-color: #555; }
        .ribbon-btn:active:not(:disabled) { background-color: #99C9FF; }
        .ribbon-btn:disabled { opacity: 0.4; cursor: not-allowed; filter: grayscale(1); }
        body.dark-mode .ribbon-btn:disabled { opacity: 0.65; } 

        .ribbon-btn.large { min-width: 60px; height: 58px; justify-content: flex-start; padding-top: 4px; }
        .ribbon-btn.large svg { width: 28px; height: 28px; stroke: var(--word-blue); stroke-width: 1.5; margin-bottom: 3px; }

        /* 外觀區：淨速上標「標記方式」— 折線／數字切換 */
        .ribbon-wpm-mark-toggle {
            position: relative;
            min-width: 60px;
            padding-left: 4px;
            padding-right: 4px;
        }
        .ribbon-wpm-mark-toggle__input {
            position: absolute;
            inset: 0;
            width: 100%;
            height: 100%;
            margin: 0;
            opacity: 0;
            cursor: pointer;
            z-index: 1;
            -webkit-appearance: none;
            appearance: none;
        }
        .ribbon-wpm-mark-toggle__icons {
            position: relative;
            z-index: 0;
            width: 28px;
            height: 28px;
            margin-bottom: 4px;
            flex-shrink: 0;
            pointer-events: none;
        }
        .ribbon-wpm-mark-toggle__icons svg {
            position: absolute;
            left: 50%;
            top: 50%;
            transform: translate(-50%, -50%);
            width: 28px;
            height: 28px;
            margin: 0;
        }
        .ribbon-btn.large .ribbon-wpm-mark-toggle__icon-l {
            stroke: var(--word-blue);
            fill: none;
            stroke-width: 1.75;
            stroke-linecap: square;
            stroke-linejoin: miter;
        }
        .ribbon-btn.large .ribbon-wpm-mark-toggle__icon-num {
            stroke: none !important;
        }
        .ribbon-wpm-mark-toggle__icon-num text {
            fill: currentColor;
            stroke: none;
            font-family: 'Segoe UI', 'Microsoft JhengHei', sans-serif;
            font-size: 13px;
            font-weight: 700;
            font-variant-numeric: tabular-nums;
        }
        .ribbon-wpm-mark-toggle:has(.ribbon-wpm-mark-toggle__input:checked) .ribbon-wpm-mark-toggle__icon-l {
            display: none;
        }
        .ribbon-wpm-mark-toggle:has(.ribbon-wpm-mark-toggle__input:not(:checked)) .ribbon-wpm-mark-toggle__icon-num {
            display: none;
        }
        .ribbon-wpm-mark-toggle > span.ribbon-wpm-mark-toggle__lbl {
            position: relative;
            z-index: 0;
            pointer-events: none;
            display: block;
            text-align: center;
            line-height: 1.2;
            white-space: nowrap;
            font-size: 12px;
            margin-top: 1px;
        }
        .ribbon-wpm-mark-toggle:has(.ribbon-wpm-mark-toggle__input:checked) {
            background-color: #C6E2FF;
            border-color: #99C9FF;
        }
        body.dark-mode .ribbon-wpm-mark-toggle:has(.ribbon-wpm-mark-toggle__input:checked) {
            background-color: #3d3d3d;
            border-color: #5a9fd4;
        }
        .ribbon-wpm-mark-toggle:has(.ribbon-wpm-mark-toggle__input:focus-visible) {
            outline: 2px solid var(--word-blue);
            outline-offset: 1px;
        }
        .ribbon-btn.large.start-btn svg { stroke: #107C41; }
        .ribbon-btn.large.stop-btn svg { stroke: #D83B01; }
        .ribbon-btn.large.quit-btn svg { stroke: #666666; }
        
        body.dark-mode .ribbon-btn.large.start-btn svg { stroke: #81c995; }
        body.dark-mode .ribbon-btn.large.stop-btn svg { stroke: #ff8a8a; }
        body.dark-mode .ribbon-btn.large.quit-btn svg { stroke: #aaaaaa; }

        /* 開發者工具：Word 2016 功能区式「大圖示在上、標籤在下」— 圖示尺寸與對齊與其他 large 按鈕一致 */
        .ribbon-btn.large.dev-ribbon-btn { min-width: 56px; max-width: 72px; padding-left: 4px; padding-right: 4px; }
        .ribbon-btn.large.dev-ribbon-btn span { text-align: center; line-height: 1.15; white-space: normal; font-size: 11px; max-width: 68px; }
        .ribbon-btn.large.dev-ribbon-btn > svg {
            display: block;
            width: 28px;
            height: 28px;
            margin-bottom: 3px;
            flex-shrink: 0;
            stroke: var(--word-blue);
            stroke-width: 1.5;
            fill: none;
        }
        body.dark-mode .ribbon-btn.large.dev-ribbon-btn > svg { stroke: var(--word-blue); }

        .dev-ribbon-panel {
            display: grid;
            grid-template-columns: 26px minmax(0, 1fr);
            grid-template-rows: auto minmax(0, 1fr);
            align-items: start;
            column-gap: 6px;
            row-gap: 3px;
            flex: 0 0 auto;
            width: 120px;
            min-width: 120px;
            max-width: 120px;
            height: 58px;
            min-height: 58px;
            max-height: 58px;
            padding: 4px 6px 4px 4px;
            box-sizing: border-box;
            border: 1px solid var(--word-border);
            border-radius: 4px;
            background: var(--word-page);
            overflow: hidden;
        }
        .dev-ribbon-panel svg.dev-ribbon-panel__glyph {
            grid-column: 1;
            grid-row: 1 / -1;
            place-self: center;
            width: 22px;
            height: 22px;
            stroke: var(--word-blue);
            stroke-width: 1.5;
            fill: none;
        }
        body.dark-mode .dev-ribbon-panel svg.dev-ribbon-panel__glyph { stroke: var(--word-blue); }
        .dev-ribbon-panel__caption {
            grid-column: 2;
            grid-row: 1;
            font-size: 9px;
            color: var(--word-text);
            text-align: left;
            line-height: 1.15;
            align-self: end;
        }
        .dev-ribbon-panel__controls {
            grid-column: 2;
            grid-row: 2;
            display: flex;
            flex-direction: column;
            gap: 2px;
            justify-content: flex-start;
            min-width: 0;
            min-height: 0;
            width: 100%;
        }
        .dev-ribbon-panel input[type="range"] {
            width: 100%;
            margin: 0;
            padding: 0;
            height: 20px;
            cursor: pointer;
            box-sizing: border-box;
            flex-shrink: 0;
        }
        .dev-ribbon-panel .ribbon-select {
            width: 100%;
            height: 24px;
            font-size: 11px;
            padding: 0 4px;
            box-sizing: border-box;
            flex-shrink: 0;
        }
        .dev-ribbon-panel .dev-auto-err-pct {
            font-size: 10px;
            font-variant-numeric: tabular-nums;
            color: var(--word-text);
            line-height: 1.1;
            flex-shrink: 0;
        }
        /* (Photoshop-style sizing for panels handled in .dev-tools-float .dev-tools-float__body > .dev-ribbon-panel above) */

        .ribbon-input-group { display: flex; flex-direction: column; gap: 4px; justify-content: center; height: 58px; }
        /* 測驗設定：第一列 語言｜模式；第二列 計分模式｜題號（題號在模式正下方，省寬） */
        .ribbon-input-group--exam-settings {
            display: grid;
            grid-template-columns: 80px 172px 16px 80px 172px;
            grid-template-rows: auto auto;
            grid-template-areas:
                "lang-lbl lang-ctl . mode-lbl mode-ctl"
                "tier-lbl tier-ctl . topic-lbl topic-ctl";
            row-gap: 6px;
            column-gap: 0;
            align-items: center;
            align-content: center;
            height: auto;
            min-height: 58px;
        }
        .ribbon-input-group--exam-settings .es-lbl {
            font-size: 13px;
            color: var(--word-text);
            text-align: right;
            white-space: nowrap;
            justify-self: end;
        }
        .ribbon-input-group--exam-settings .es-ctl {
            min-width: 0;
            justify-self: stretch;
        }
        .ribbon-input-group--exam-settings .es-ctl .ribbon-select {
            width: 100%;
            box-sizing: border-box;
        }
        .ribbon-input-group--exam-settings .es-lang-lbl { grid-area: lang-lbl; }
        .ribbon-input-group--exam-settings .es-lang-ctl { grid-area: lang-ctl; }
        .ribbon-input-group--exam-settings .es-mode-lbl { grid-area: mode-lbl; }
        .ribbon-input-group--exam-settings .es-mode-ctl { grid-area: mode-ctl; }
        .ribbon-input-group--exam-settings .es-topic-lbl { grid-area: topic-lbl; }
        .ribbon-input-group--exam-settings .es-topic-ctl { grid-area: topic-ctl; }
        .ribbon-input-group--exam-settings .es-tier-lbl { grid-area: tier-lbl; }
        .ribbon-input-group--exam-settings .es-tier-ctl { grid-area: tier-ctl; }
        .ribbon-input-group--exam-settings .es-topic-inner {
            display: flex;
            width: 100%;
            max-width: 172px;
            align-items: stretch;
            height: 26px;
            box-sizing: border-box;
        }
        .wpm-tier-picker {
            position: relative;
            width: 100%;
            max-width: 172px;
            flex-shrink: 0;
        }
        .wpm-tier-select-hidden {
            position: absolute !important;
            left: -9999px !important;
            width: 1px !important;
            height: 1px !important;
            margin: 0 !important;
            padding: 0 !important;
            border: 0 !important;
            opacity: 0 !important;
            pointer-events: none !important;
            overflow: hidden !important;
        }
        .wpm-tier-face {
            width: 100%;
            height: 26px;
            padding: 0 8px;
            font-family: var(--ui-font);
            font-size: 13px;
            border: 1px solid var(--word-border);
            outline: none;
            background: var(--word-page);
            color: var(--word-text);
            border-radius: 2px;
            box-sizing: border-box;
            cursor: pointer;
            text-align: left;
            display: flex;
            align-items: center;
            justify-content: space-between;
            gap: 6px;
        }
        .wpm-tier-face:disabled {
            opacity: 0.55;
            cursor: not-allowed;
        }
        .wpm-tier-face:focus {
            border-color: var(--word-blue);
        }
        .wpm-tier-face__chev {
            flex-shrink: 0;
            width: 0;
            height: 0;
            border-left: 4px solid transparent;
            border-right: 4px solid transparent;
            border-top: 5px solid var(--word-text-light);
            margin-top: 2px;
            opacity: 0.85;
        }
        /* fixed + JS 定位：避免 ribbon overflow 裁切清單 */
        .wpm-tier-menu {
            position: fixed;
            left: 0;
            top: 0;
            z-index: 10050;
            margin: 0;
            padding: 4px 0;
            list-style: none;
            background: var(--word-page);
            color: var(--word-text);
            border: 1px solid var(--word-border);
            border-radius: 4px;
            box-shadow: 0 8px 24px rgba(0, 0, 0, 0.15);
            box-sizing: border-box;
            min-width: 0;
            width: max-content;
            max-width: min(420px, calc(100vw - 24px));
        }
        .wpm-tier-menu li {
            padding: 8px 12px;
            cursor: pointer;
            font-size: 13px;
            line-height: 1.4;
            white-space: normal;
        }
        .wpm-tier-menu li:hover {
            background: #C6E2FF;
        }
        body.dark-mode .wpm-tier-menu li:hover {
            background: #444;
        }
        .wpm-tier-menu li[aria-selected="true"] {
            font-weight: 600;
        }
        .ribbon-select-row { display: flex; align-items: center; gap: 8px; font-size: 13px; }
        .ribbon-select-row > span { display: inline-block; width: 45px; text-align: right; color: var(--word-text); white-space: nowrap; flex-shrink: 0; }
        
        .ribbon-select { height: 26px; padding: 0 6px; font-family: var(--ui-font); font-size: 13px; border: 1px solid var(--word-border); outline: none; background: var(--word-page); color: var(--word-text); border-radius: 2px; box-sizing: border-box; vertical-align: middle; }
        .ribbon-select:focus { border-color: var(--word-blue); }

        .dice-btn {
            width: 26px; height: 26px; display: inline-flex; align-items: center; justify-content: center;
            background: var(--word-page); border: 1px solid var(--word-border); border-radius: 2px;
            cursor: pointer; color: var(--word-text); transition: all 0.1s; padding: 0; font-size: 14px; box-sizing: border-box; vertical-align: middle;
        }
        .dice-btn:hover { background: #C6E2FF; border-color: #99C9FF; }
        body.dark-mode .dice-btn { background: #333; border-color: #555; }
        body.dark-mode .dice-btn:hover { background: #444; border-color: #777; }

        .exam-mode-lbl {
            font-size: 12px; display: flex; align-items: center; gap: 6px; cursor: pointer; color: var(--word-text);
            padding: 6px 8px; border-radius: 4px; transition: background 0.2s; margin: 0; white-space: nowrap;
        }
        .exam-mode-lbl input[type="checkbox"] { margin: 0; width: 14px; height: 14px; cursor: pointer; }
        .exam-mode-lbl:hover { background-color: rgba(0,0,0,0.05); }
        body.dark-mode .exam-mode-lbl:hover { background-color: rgba(255,255,255,0.1); }

        .ribbon-timer { font-size: 28px; font-weight: 300; color: var(--word-blue); font-variant-numeric: tabular-nums; padding: 0 15px; margin-bottom: 0; }