* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #667eea;
    --primary-dark: #764ba2;
    --bg-color: #f8f9fa;
    --sidebar-bg: #ffffff;
    --border-color: #e1e4e8;
    --text-color: #24292e;
    --text-secondary: #586069;
    --editor-bg: #fafbfc;
    --preview-bg: #ffffff;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
    background: var(--bg-color);
    color: var(--text-color);
    height: 100vh;
    overflow: hidden;
}

#app {
    height: 100vh;
    display: flex;
    flex-direction: column;
}

.header {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    color: white;
    padding: 0 24px;
    height: 60px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    z-index: 100;
}

.header-left {
    display: flex;
    align-items: center;
}

.logo {
    font-size: 20px;
    font-weight: 600;
    letter-spacing: 0.5px;
}

.header-right {
    display: flex;
    gap: 12px;
}

.header-btn {
    background: rgba(255, 255, 255, 0.15);
    border: 1px solid rgba(255, 255, 255, 0.3);
    color: white;
    padding: 8px 16px;
    border-radius: 6px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 14px;
    transition: all 0.3s ease;
}

.header-btn:hover {
    background: rgba(255, 255, 255, 0.25);
    transform: translateY(-1px);
}

.header-btn.primary {
    background: white;
    color: var(--primary-color);
    border: none;
    font-weight: 500;
}

.header-btn.primary:hover {
    background: #f0f0f0;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.main-container {
    flex: 1;
    display: flex;
    overflow: hidden;
}

.sidebar {
    width: 280px;
    background: var(--sidebar-bg);
    border-right: 1px solid var(--border-color);
    overflow-y: auto;
    padding: 20px;
}

.sidebar-section {
    margin-bottom: 24px;
}

.sidebar-title {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 12px;
    padding-bottom: 8px;
    border-bottom: 1px solid var(--border-color);
}

.theme-list {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 10px;
}

.theme-item {
    cursor: pointer;
    padding: 8px;
    border: 2px solid transparent;
    border-radius: 8px;
    transition: all 0.3s ease;
    text-align: center;
}

.theme-item:hover {
    border-color: var(--primary-color);
    background: #f6f8fa;
}

.theme-item.active {
    border-color: var(--primary-color);
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1) 0%, rgba(118, 75, 162, 0.1) 100%);
}

.theme-preview {
    width: 100%;
    height: 40px;
    border-radius: 6px;
    margin-bottom: 6px;
}

.theme-item span {
    font-size: 12px;
    color: var(--text-secondary);
}

.config-item {
    margin-bottom: 16px;
}

.config-item label {
    display: block;
    font-size: 13px;
    color: var(--text-secondary);
    margin-bottom: 6px;
}

.config-item select {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    background: white;
    font-size: 14px;
    cursor: pointer;
}

.config-item select:focus {
    outline: none;
    border-color: var(--primary-color);
}

.config-item input[type="checkbox"] {
    margin-right: 8px;
}

.sidebar-btn {
    width: 100%;
    padding: 10px 16px;
    margin-bottom: 10px;
    background: white;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 14px;
    color: var(--text-color);
    transition: all 0.3s ease;
}

.sidebar-btn:hover {
    border-color: var(--primary-color);
    background: #f6f8fa;
}

.editor-container {
    flex: 1;
    display: flex;
    gap: 0;
    overflow: hidden;
}

.editor-wrapper,
.preview-wrapper {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.editor-wrapper {
    border-right: 1px solid var(--border-color);
}

.editor-header,
.preview-header {
    background: #f6f8fa;
    padding: 12px 20px;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-weight: 600;
    font-size: 14px;
    color: var(--text-secondary);
}

.editor-tools,
.preview-tools {
    display: flex;
    gap: 4px;
    align-items: center;
}

.tool-btn {
    padding: 6px 10px;
    background: white;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    cursor: pointer;
    font-size: 13px;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: 32px;
}

.tool-btn:hover {
    background: #f6f8fa;
    border-color: var(--primary-color);
}

.tool-btn strong {
    font-weight: 700;
}

.tool-btn em {
    font-style: italic;
}

.tool-divider {
    width: 1px;
    height: 20px;
    background: var(--border-color);
    margin: 0 4px;
}

.preview-tool-btn {
    padding: 6px 12px;
    background: white;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    cursor: pointer;
    font-size: 13px;
    display: flex;
    align-items: center;
    gap: 6px;
    transition: all 0.2s;
}

.preview-tool-btn:hover {
    background: #f6f8fa;
    border-color: var(--primary-color);
}

#editor {
    flex: 1;
    padding: 20px;
    border: none;
    resize: none;
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', 'Consolas', monospace;
    font-size: 14px;
    line-height: 1.6;
    outline: none;
    background: var(--editor-bg);
    color: var(--text-color);
}

#editor::placeholder {
    color: #c0c4cc;
}

.preview-content {
    flex: 1;
    padding: 30px 40px;
    overflow-y: auto;
    background: var(--preview-bg);
}

.preview-content h1 {
    font-size: 26px;
    font-weight: 700;
    color: #000;
    margin: 24px 0 16px;
    padding-bottom: 12px;
    border-bottom: 2px solid var(--primary-color);
}

.preview-content h2 {
    font-size: 22px;
    font-weight: 600;
    color: #000;
    margin: 22px 0 14px;
    padding-left: 12px;
    border-left: 4px solid var(--primary-color);
}

.preview-content h3 {
    font-size: 18px;
    font-weight: 600;
    color: #000;
    margin: 20px 0 12px;
}

.preview-content h4 {
    font-size: 16px;
    font-weight: 600;
    color: #000;
    margin: 18px 0 10px;
}

.preview-content p {
    margin-bottom: 16px;
    line-height: 1.75;
    text-align: justify;
}

.preview-content strong {
    font-weight: 600;
    color: #000;
}

.preview-content em {
    font-style: italic;
    color: var(--text-secondary);
}

.preview-content a {
    color: var(--primary-color);
    text-decoration: none;
    border-bottom: 1px solid var(--primary-color);
}

.preview-content blockquote {
    margin: 20px 0;
    padding: 16px 20px;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.05) 0%, rgba(118, 75, 162, 0.05) 100%);
    border-left: 4px solid var(--primary-color);
    border-radius: 4px;
    color: var(--text-secondary);
}

.preview-content blockquote p {
    margin-bottom: 0;
}

.preview-content ul,
.preview-content ol {
    margin: 16px 0;
    padding-left: 28px;
}

.preview-content li {
    margin-bottom: 8px;
    line-height: 1.75;
}

.preview-content ul li {
    list-style-type: disc;
}

.preview-content ol li {
    list-style-type: decimal;
}

.preview-content code {
    background: rgba(27, 31, 35, 0.05);
    padding: 3px 6px;
    border-radius: 3px;
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', 'Consolas', monospace;
    font-size: 0.9em;
    color: #d73a49;
}

.preview-content pre {
    margin: 20px 0;
    padding: 16px;
    background: #282c34;
    border-radius: 8px;
    overflow-x: auto;
    position: relative;
}

.preview-content pre code {
    background: transparent;
    padding: 0;
    color: #abb2bf;
    font-size: 14px;
    line-height: 1.6;
}

.preview-content img {
    max-width: 100%;
    display: block;
    margin: 20px auto;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.preview-content table {
    width: 100%;
    margin: 20px 0;
    border-collapse: collapse;
    border-radius: 8px;
    overflow: hidden;
}

.preview-content th,
.preview-content td {
    padding: 12px 16px;
    border: 1px solid var(--border-color);
    text-align: left;
}

.preview-content th {
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1) 0%, rgba(118, 75, 162, 0.1) 100%);
    font-weight: 600;
}

.preview-content tr:nth-child(even) {
    background: #f6f8fa;
}

.preview-content hr {
    border: none;
    height: 2px;
    background: linear-gradient(90deg, var(--primary-color), var(--primary-dark));
    margin: 30px 0;
    border-radius: 2px;
}

.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    animation: fadeIn 0.3s ease;
}

.modal-content {
    background-color: white;
    margin: 10% auto;
    padding: 30px;
    border-radius: 12px;
    width: 90%;
    max-width: 500px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
    animation: slideIn 0.3s ease;
    position: relative;
}

.modal-close {
    position: absolute;
    right: 20px;
    top: 20px;
    color: #aaa;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
    transition: color 0.3s;
}

.modal-close:hover {
    color: #000;
}

.modal h2 {
    margin-bottom: 20px;
    color: var(--text-color);
}

.modal .form-group {
    margin-bottom: 20px;
}

.modal label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: var(--text-secondary);
    font-size: 14px;
}

.modal input[type="text"],
.modal input[type="password"] {
    width: 100%;
    padding: 12px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 14px;
    transition: border-color 0.3s;
}

.modal input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.modal .btn {
    width: 100%;
    padding: 12px;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    transition: all 0.3s ease;
}

.modal .btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.3);
}

.toast {
    position: fixed;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    background: #333;
    color: white;
    padding: 12px 24px;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    z-index: 2000;
    opacity: 0;
    transition: opacity 0.3s ease;
    font-size: 14px;
}

.toast.show {
    opacity: 1;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes slideIn {
    from {
        transform: translateY(-50px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

@media (max-width: 1200px) {
    .sidebar {
        width: 240px;
    }
}

@media (max-width: 768px) {
    .main-container {
        flex-direction: column;
    }

    .sidebar {
        width: 100%;
        height: auto;
        border-right: none;
        border-bottom: 1px solid var(--border-color);
    }

    .editor-container {
        flex-direction: column;
    }

    .editor-wrapper {
        border-right: none;
        border-bottom: 1px solid var(--border-color);
    }

    .header {
        padding: 0 16px;
    }

    .header-btn span {
        display: none;
    }

    .header-btn {
        padding: 8px 12px;
    }
}

.code-wrapper {
    margin: 20px 0;
    border-radius: 8px;
    overflow: hidden;
    background: #282c34;
}

.code-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px 16px;
    background: #21252b;
    border-bottom: 1px solid #333;
}

.code-lang {
    font-size: 12px;
    color: #abb2bf;
    font-weight: 500;
}

.code-copy-btn {
    padding: 4px 12px;
    background: transparent;
    border: 1px solid #abb2bf;
    border-radius: 4px;
    color: #abb2bf;
    font-size: 12px;
    cursor: pointer;
    transition: all 0.2s;
}

.code-copy-btn:hover {
    background: #abb2bf;
    color: #282c34;
}

.preview-content .code-wrapper pre {
    margin: 0;
    border-radius: 0;
}

.line-number {
    display: inline-block;
    width: 40px;
    margin-right: 16px;
    color: #636d83;
    text-align: right;
    user-select: none;
}

.project-tree {
    margin-top: 20px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    overflow: hidden;
}

.tree-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 16px;
    background: #f6f8fa;
    border-bottom: 1px solid var(--border-color);
    font-weight: 600;
    font-size: 14px;
}

.tree-refresh {
    background: transparent;
    border: none;
    cursor: pointer;
    font-size: 16px;
    padding: 4px 8px;
    border-radius: 4px;
    transition: background 0.2s;
}

.tree-refresh:hover {
    background: #e1e4e8;
}

.file-tree {
    max-height: 400px;
    overflow-y: auto;
    background: white;
}

.tree-item {
    padding: 8px 12px;
    cursor: pointer;
    transition: background 0.2s;
    border-bottom: 1px solid #f0f0f0;
}

.tree-item:hover {
    background: #f6f8fa;
}

.tree-item.folder {
    font-weight: 500;
}

.tree-item.file {
    color: var(--text-color);
}

.tree-item-name {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 14px;
}

.tree-children {
    margin-left: 0;
}

.tree-item.collapsed > .tree-item-name::before {
    content: '▶';
    font-size: 10px;
    margin-right: 4px;
    transition: transform 0.2s;
}

.tree-item.expanded > .tree-item-name::before {
    content: '▶';
    font-size: 10px;
    margin-right: 4px;
    transform: rotate(90deg);
    display: inline-block;
}

.tree-item.file > .tree-item-name::before {
    content: '';
}

.loading-status {
    margin-top: 15px;
    padding: 12px;
    text-align: center;
    color: var(--text-secondary);
    font-size: 14px;
}

.loading-status.error {
    color: #d73a49;
    background: #ffeef0;
    border-radius: 6px;
}

.loading-spinner {
    display: inline-block;
    width: 16px;
    height: 16px;
    border: 2px solid #f3f3f3;
    border-top: 2px solid var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-right: 8px;
    vertical-align: middle;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.tree-error {
    padding: 12px;
    text-align: center;
    color: #d73a49;
    font-size: 13px;
}