:root {
    --bg-color: #f4f4f4;
    --text-color: #333;
    --header-bg: #333;
    --header-text: white;
    --panel-bg: #fcfcfc;
    --panel-border: #ccc;
    --editor-bg: #fff;
    --button-bg: #007bff;
    --button-text: white;
    --button-hover-bg: #0056b3;
    --input-bg: #fff;
    --input-border: #ccc;
    --selected-bg: #007bff;
    --selected-text: white;
    --hover-bg: #f0f0f0;
    --hr-color: #ccc;
    --link-color: #007bff;
    --disabled-text: #ccc;
    --footer-bg: #f0f0f0;
    --tool-panel-bg: #f9f9f9;
    --tool-header-bg: #f8f9fa;
    --tool-header-border: #dee2e6;
}

body[data-theme="dark"] {
    --bg-color: #2d2d2d;
    --text-color: #e0e0e0;
    --header-bg: #1e1e1e;
    --header-text: #e0e0e0;
    --panel-bg: #252525;
    --panel-border: #424242;
    --editor-bg: #1e1e1e;
    --button-bg: #007bff;
    --button-text: white;
    --button-hover-bg: #0056b3;
    --input-bg: #3a3a3a;
    --input-border: #555;
    --selected-bg: #007bff;
    --selected-text: white;
    --hover-bg: #3a3a3a;
    --hr-color: #424242;
    --link-color: #3498db;
    --disabled-text: #555;
    --footer-bg: #2a2a2a;
    --tool-panel-bg: #252525;
    --tool-header-bg: #1e1e1e;
    --tool-header-border: #424242;
}

/* 全体レイアウト */
body {
    font-family: sans-serif;
    margin: 0;
    background-color: var(--bg-color);
    color: var(--text-color);
    display: flex;
    flex-direction: column;
    height: 100vh;
    transition: background-color 0.3s, color 0.3s;
    overflow: hidden; /* ページ全体のスクロールを禁止 */
}

header {
    background-color: var(--header-bg);
    color: var(--header-text);
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-shrink: 0;
}

header h1 {
    font-size: 1.5em;
    margin: 10px 0;
}

header button {
    background-color: transparent;
    border: 1px solid #555;
    color: #eee;
    padding: 5px 10px;
}
header button:hover {
    background-color: #555;
}

.header-controls-right {
    display: flex;
    align-items: center;
    gap: 10px;
}

#theme-toggle-btn {
    background: none;
    border: 1px solid #777;
    color: var(--header-text);
    font-size: 1.2em;
}

.mode-switcher button {
    padding: 6px 12px;
    background-color: #555;
    border: 1px solid #777;
    color: white;
}
.mode-switcher button:hover {
    background-color: #777;
}

.workspace {
    display: flex;
    flex: 1;
    overflow-y: auto;
    overflow-x: hidden;
}

.panel {
    padding: 20px;
    box-sizing: border-box;
    overflow-y: auto;
    transition: min-width 0.3s ease, padding 0.3s ease, width 0.3s ease, background-color 0.3s;
    border-right: 1px solid var(--panel-border);
}
.panel:last-child {
    border-right: none;
}

.tree-panel {
    flex: 0 0 300px;
    min-width: 300px;
    background-color: var(--panel-bg);
    display: flex;
    flex-direction: column;
}

.panel-controls {
    display: flex;
    flex-direction: column;
    gap: 10px;
    padding-bottom: 10px;
}
.panel-controls button {
    width: 100%;
    padding: 8px 15px;
    text-align: left;
    background-color: #555;
}
body[data-theme="dark"] .panel-controls button {
    background-color: #3a3a3a;
}

.editor-panel {
    flex: 1 1 0;
    min-width: 400px;
    background-color: var(--editor-bg);
    display: flex;
    flex-direction: column;
}

.tools-panel {
    flex: 0 0 400px;
    min-width: 400px;
    background-color: var(--tool-panel-bg);
}

.panel.collapsed {
    flex-basis: 0;
    width: 0;
    min-width: 0;
    padding: 20px 0;
    border-right: none;
    overflow: hidden;
}

hr {
    border: 0;
    border-top: 1px solid var(--hr-color);
    margin: 20px 0;
}

body[data-mode="project"] #simple-mode-ui {
    display: none;
}
body[data-mode="simple"] #project-mode-ui {
    display: none;
}
.list-view-section {
    display: flex;
    flex-direction: column;
    flex: 1;
    min-height: 0;
}
.list-view-section h2 {
    margin-top: 0;
    font-size: 1.2em;
    border-bottom: 2px solid var(--text-color);
    padding-bottom: 5px;
}
.project-list-container {
    flex: 1;
    overflow-y: auto;
    border: 1px solid var(--panel-border);
    padding: 10px;
    margin-bottom: 10px;
    background-color: var(--input-bg);
}
.project-list-container ul {
    list-style-type: none;
    padding: 0;
    margin: 0;
}
.project-list-container .list-item {
    padding: 4px;
    border-radius: 4px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 5px;
}
.project-list-container .list-item:hover {
    background-color: var(--hover-bg);
}
.project-list-container .list-item.selected > span {
    background-color: var(--selected-bg);
    color: var(--selected-text);
}
.project-list-container .list-item > span {
    flex-grow: 1;
    padding: 2px 4px;
    border-radius: 3px;
}
.project-list-container .list-item input[type="checkbox"] {
    flex-shrink: 0;
    margin: 0;
}
.project-list-container .list-item-project {
    font-weight: bold;
    font-size: 1.1em;
    margin-top: 10px;
}
.project-list-container .list-item-project:first-child {
    margin-top: 0;
}
.project-list-container .list-item-chapter {
    padding-left: 20px;
}
.project-list-container .list-item-version {
    padding-left: 40px;
    font-style: italic;
}
.list-item.collapsible > span::before {
    content: '▼ ';
    font-size: 0.8em;
}
.list-item.collapsible.collapsed > span::before {
    content: '► ';
}
.project-list-container ul.collapsed {
    display: none;
}
.tree-action-buttons {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 10px;
}
.tree-import-button {
    margin-top: 10px;
}
.tree-import-button button {
    width: 100%;
}
.action-hr {
    margin: 15px 0;
    border: none;
    border-top: 1px solid var(--hr-color);
}
.batch-export-section {
    display: flex;
    flex-direction: column;
    gap: 10px;
}
.reorder-buttons {
    display: flex;
    gap: 10px;
}
.reorder-buttons button {
    flex: 1;
    font-size: 1.2em;
    padding: 5px;
    line-height: 1;
}
.batch-export-section button {
    width: 100%;
    padding: 8px;
    font-size: 0.9em;
}
.bulk-export-container {
    display: grid;
    grid-template-columns: 1fr;
    gap: 10px;
}
#bulk-export-format {
    width: 100%;
    padding: 5px;
    height: auto;
}
#delete-item-btn {
    background-color: #c82333;
}
#delete-item-btn:hover {
    background-color: #a71d2a;
}
#export-selected-btn {
    background-color: #17a2b8;
}
#export-selected-btn:hover {
    background-color: #138496;
}
#bulk-export-btn {
    background-color: #28a745;
}
#bulk-export-btn:hover {
    background-color: #218838;
}
#bulk-convert-btn {
    background-color: #ffc107;
    color: #212529;
}
#bulk-convert-btn:hover {
    background-color: #e0a800;
}
#simple-work-list {
    width: 100%;
    margin-bottom: 10px;
    border-radius: 4px;
    padding: 5px;
    height: 225px;
    background-color: var(--input-bg);
    color: var(--text-color);
    border: 1px solid var(--input-border);
}
.simple-controls {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: 10px;
}
#delete-simple-work-btn {
    background-color: #c82333;
}
#delete-simple-work-btn:hover {
    background-color: #a71d2a;
}
.writing-area {
    display: flex;
    flex-direction: column;
    flex: 1;
    min-height: 0;
}
input[type="text"] {
    padding: 8px;
    border: 1px solid var(--input-border);
    background-color: var(--input-bg);
    color: var(--text-color);
    border-radius: 4px;
    box-sizing: border-box;
    height: 40px;
}
#editor-title {
    font-size: 1.2em;
    margin-bottom: 10px;
}
#work-content {
    flex: 1;
    width: 100%;
    padding: 15px;
    box-sizing: border-box;
    border: 1px solid var(--input-border);
    background-color: var(--input-bg);
    color: var(--text-color);
    border-radius: 4px;
    font-size: 16px;
    line-height: 1.6;
    resize: none;
}
.editor-footer {
    display: flex;
    align-items: center;
    gap: 15px;
    margin-top: 10px;
    padding: 10px;
    background-color: var(--footer-bg);
    border-top: 1px solid var(--panel-border);
    flex-shrink: 0;
}
.undo-redo-buttons button,
.font-size-controls button {
    background-color: transparent;
    color: var(--text-color);
    border: 1px solid var(--panel-border);
    font-size: 1.2em;
    padding: 2px 8px;
    line-height: 1;
    border-radius: 4px;
    min-width: 28px;
}
.undo-redo-buttons button:hover,
.font-size-controls button:hover {
    background-color: var(--hover-bg);
}
.undo-redo-buttons button:disabled {
    color: var(--disabled-text);
    cursor: not-allowed;
    background-color: transparent;
}
.font-size-controls {
    display: flex;
    align-items: center;
    gap: 5px;
}
#char-counter {
    color: #666;
}
body[data-theme="dark"] #char-counter {
    color: #999;
}
#save-btn {
    margin-left: auto;
    min-width: 80px;
}
#save-btn.save-success {
    background-color: #28a745;
    border-color: #28a745;
}
.export-section {
    display: flex;
    gap: 10px;
    align-items: center;
    padding: 10px;
    background-color: var(--footer-bg);
    border-top: 1px solid var(--panel-border);
    flex-shrink: 0;
}
#export-format, #bulk-export-format {
    flex-grow: 1;
    padding: 8px;
    height: auto;
    background-color: var(--input-bg);
    color: var(--text-color);
    border: 1px solid var(--input-border);
}
.tool-section {
    display: flex;
    flex-direction: column;
    gap: 10px;
}
.tool-section h2 {
    margin-top: 0;
    margin-bottom: 0;
    border-bottom: 2px solid var(--text-color);
    padding-bottom: 5px;
}
.controls {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 10px;
    margin-bottom: 0;
}
.ruby-form {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 10px;
    margin-bottom: 0;
}
.ruby-form-actions {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 10px;
    margin-top: 0;
}
.ruby-controls button {
    width: 100%;
    margin-top: 0;
}
#ruby-list-container {
    margin-top: 0;
    margin-bottom: 0;
}
#ruby-list-container h3 {
    margin-top: 0;
}
#ruby-list {
    list-style: none;
    padding: 0;
    max-height: 200px;
    overflow-y: auto;
    border: 1px solid var(--input-border);
    background-color: var(--input-bg);
    padding: 10px;
    border-radius: 4px;
}
#ruby-list li {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 5px;
    border-bottom: 1px solid var(--panel-border);
}
#ruby-list li:last-child {
    border-bottom: none;
}
.ruby-io-buttons {
    display: flex;
    gap: 10px;
    margin-bottom: 0;
}
.ruby-io-buttons button {
    flex: 1;
}
.other-tools {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 10px;
}
button {
    padding: 10px 15px;
    background-color: var(--button-bg);
    color: var(--button-text);
    border: none;
    border-radius: 4px;
    cursor: pointer;
    transition: background-color 0.2s, border-color 0.2s;
}
button:hover {
    background-color: var(--button-hover-bg);
}
.delete-ruby {
    background-color: #dc3545;
}
.delete-ruby:hover {
    background-color: #c82333;
}
#mobile-menu-btn,
#close-left-panel-btn,
.panel-controls {
    display: none;
}
#tools-panel #footer-handle,
#tools-panel #tools-menu,
#tools-panel #tool-back-btn {
    display: none;
}

/* ===================================
    レスポンシブデザイン対応
====================================== */
@media (max-width: 768px) {
    body {
        overflow: auto;
    }
    .workspace {
        flex-direction: column;
        height: auto;
        overflow: visible;
    }
    header {
        display: flex;
        justify-content: space-between;
        align-items: center;
        padding: 0 10px;
    }
    header h1 {
        flex-grow: 1;
        text-align: center;
        font-size: 1.2em;
    }
    header #toggle-left-panel-btn,
    header #toggle-right-panel-btn,
    .header-controls-right {
        display: none;
    }
    #mobile-menu-btn {
        display: block;
        padding: 5px 10px;
    }
    #tree-panel {
        position: fixed;
        left: 0;
        top: 0;
        height: 100%;
        width: 80%;
        max-width: 320px;
        z-index: 200;
        background-color: var(--panel-bg);
        box-shadow: 2px 0 5px rgba(0,0,0,0.2);
        transform: translateX(-100%);
        transition: transform 0.3s ease-in-out;
    }
    #tree-panel.open {
        transform: translateX(0);
    }
    #close-left-panel-btn,
    .panel-controls {
        display: block;
    }
    .panel-controls {
        display: flex;
        flex-direction: column;
    }
    .editor-panel {
        flex: 1 1 auto;
        min-height: 0;
        border-right: none;
    }
    .editor-footer {
        flex-wrap: wrap;
        gap: 10px;
    }
    #tools-panel {
        position: fixed;
        left: 0;
        width: 100%;
        height: 50vh;
        z-index: 100;
        background-color: var(--tool-panel-bg);
        border-top: 1px solid var(--panel-border);
        box-shadow: 0 -2px 5px rgba(0, 0, 0, 0.1);
        transition: transform 0.3s ease-in-out;
        bottom: 0;
        transform: translateY(calc(100% - 40px));
        display: flex;
        padding: 0;
        flex-direction: column;
    }
    #tools-panel.menu-open {
        transform: translateY(calc(100% - 220px));
    }
    #tools-panel.tool-open {
        transform: translateY(0);
    }
    #tools-panel #footer-handle {
        display: block;
    }
    #tools-panel #tools-menu {
        display: grid;
    }
    .tool-section-container {
        display: none;
    }
    #tools-panel.tool-open #tools-menu,
    #tools-panel.tool-open #footer-handle {
        display: none;
    }
    #tools-panel.tool-open .tool-section-container {
        display: flex;
        flex-direction: column;
        overflow-y: auto; /* ツールパネル自体をスクロール可能に */
    }
    #tools-panel #tool-back-btn {
        display: block;
    }
    #footer-handle {
        width: 100%;
        height: 40px;
        position: relative;
        cursor: pointer;
        background-color: var(--tool-header-bg);
        border-top: 1px solid var(--tool-header-border);
        box-shadow: 0 -2px 5px rgba(0, 0, 0, 0.05);
        flex-shrink: 0;
    }
    #footer-handle::before {
        content: '';
        display: block;
        width: 40px;
        height: 4px;
        background-color: #ced4da;
        border-radius: 2px;
        position: absolute;
        bottom: 8px;
        left: 50%;
        transform: translateX(-50%);
    }
    #footer-handle::after {
        content: '▲';
        font-size: 10px;
        color: #868e96;
        position: absolute;
        top: 6px;
        left: 50%;
        transform: translateX(-50%);
    }
    #tools-panel #tools-menu {
        grid-template-columns: 1fr 1fr;
        padding: 20px;
        gap: 15px;
    }
    .tool-menu-btn {
        width: 100%;
        text-align: center;
        padding: 15px;
        font-size: 1.1em;
        background-color: var(--button-bg);
        border: none;
        color: var(--button-text);
        border-radius: 4px;
        transition: background-color 0.2s;
    }
    .tool-menu-btn:hover {
        background-color: var(--button-hover-bg);
    }
    #menu-overlay {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        background: rgba(0,0,0,0.5);
        z-index: 199;
        display: none;
    }
    #tools-panel #tool-back-btn {
        padding: 10px;
        background-color: var(--tool-header-bg);
        border: none;
        border-bottom: 1px solid var(--panel-border);
        text-align: left;
        font-weight: bold;
        flex-shrink: 0;
    }
    .tool-section {
        display: none;
        padding: 5px;
    }
    .tool-section.active {
        display: flex;
        flex-direction: column; /* ★★★ 修正点 ★★★ */
    }
    #editor-panel {
        position: relative;
        z-index: 1;
    }
    .tool-header {
        display: flex;
        justify-content: space-between;
        align-items: center;
        padding: 0 10px;
        height: 44px;
        background-color: var(--tool-header-bg);
        border-bottom: 1px solid var(--tool-header-border);
        flex-shrink: 0;
    }
    #tool-back-btn,
    #tool-close-btn {
        background: none;
        border: none;
        color: var(--link-color);
        font-size: 1em;
        padding: 5px 10px;
    }
    #tool-close-btn {
        color: #6c757d;
    }
    .panel-header {
        display: flex;
        justify-content: space-between;
        align-items: center;
        margin-bottom: 10px;
    }
    .panel-header h2 {
        margin: 0;
    }
    .ruby-form-actions,
    .ruby-io-buttons,
    .other-tools,
    .controls {
        gap: 15px;
    }
    .tool-section-container hr {
        display: none;
    }
}

/* モーダルスタイル */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0,0,0,0.5);
}

.modal-content {
    background-color: var(--panel-bg);
    margin: 5% auto;
    padding: 0;
    border: 1px solid var(--panel-border);
    width: 90%;
    max-width: 800px;
    max-height: 80vh;
    border-radius: 8px;
    display: flex;
    flex-direction: column;
}

.modal-header {
    padding: 15px 20px;
    background-color: var(--header-bg);
    color: var(--header-text);
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-radius: 8px 8px 0 0;
}

.modal-header h2 {
    margin: 0;
}

.close-modal {
    color: var(--header-text);
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
}

.close-modal:hover {
    opacity: 0.7;
}

.modal-body {
    padding: 20px;
    overflow-y: auto;
    flex: 1;
}

.modal-body h1 { font-size: 1.8em; margin-top: 0; }
.modal-body h2 { font-size: 1.4em; margin-top: 20px; }
.modal-body h3 { font-size: 1.2em; margin-top: 15px; }
.modal-body ul { padding-left: 30px; }
.modal-body li { margin: 5px 0; }
.modal-body code {
    background-color: var(--input-bg);
    padding: 2px 5px;
    border-radius: 3px;
    font-family: monospace;
}

/* iOS Safari専用スタイル調整 */
@supports (-webkit-touch-callout: none) {
    #ruby-word,
    #ruby-reading {
        font-size: 16px;
        -webkit-appearance: none;
    }
    
    #get-selection-btn {
        background-color: #6c757d;
        margin-top: 10px;
    }
    
    #get-selection-btn:active {
        background-color: #5a6268;
    }
    
    /* iOS入力フィールドのズーム防止 */
    input[type="text"],
    textarea {
        font-size: 16px;
    }
}