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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Malgun Gothic", "맑은 고딕", sans-serif;
    background: #f5f5f5;
    min-height: 100vh;
    padding: 20px;
    line-height: 1.6;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    background: #fff;
    border: 1px solid #ddd;
}

header {
    background: #2c3e50;
    color: #fff;
    padding: 25px 30px;
    border-bottom: 3px solid #1a252f;
}

h1 {
    font-size: 1.6rem;
    font-weight: 600;
    margin-bottom: 15px;
}

.info-box {
    background: #34495e;
    padding: 12px 18px;
    display: inline-block;
    border-left: 3px solid #3498db;
}

.info-box p {
    margin: 3px 0;
    font-size: 0.95rem;
    color: #ecf0f1;
}

main {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0;
    min-height: 500px;
}

h2 {
    color: #333;
    font-size: 1.1rem;
    font-weight: 600;
}

/* Editor Section */
.editor-section {
    border-right: 1px solid #ddd;
    display: flex;
    flex-direction: column;
}

.editor-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 20px;
    background: #f8f9fa;
    border-bottom: 1px solid #e0e0e0;
    flex-wrap: wrap;
    gap: 10px;
}

.editor-actions {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

.file-label {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 14px;
    background: #3498db;
    color: #fff;
    font-size: 0.85rem;
    font-weight: 500;
    cursor: pointer;
    transition: background 0.2s;
}

.file-label:hover {
    background: #2980b9;
}

.sample-btn {
    padding: 8px 14px;
    background: #27ae60;
    color: #fff;
    border: none;
    font-size: 0.85rem;
    font-weight: 500;
    cursor: pointer;
    transition: background 0.2s;
}

.sample-btn:hover {
    background: #219a52;
}

.clear-btn {
    padding: 8px 14px;
    background: #95a5a6;
    color: #fff;
    border: none;
    font-size: 0.85rem;
    font-weight: 500;
    cursor: pointer;
    transition: background 0.2s;
}

.clear-btn:hover {
    background: #7f8c8d;
}

#md-input {
    flex: 1;
    width: 100%;
    padding: 20px;
    border: none;
    resize: none;
    font-family: "Consolas", "Monaco", "Courier New", monospace;
    font-size: 0.95rem;
    line-height: 1.6;
    background: #fff;
}

#md-input:focus {
    outline: none;
}

#md-input::placeholder {
    color: #aaa;
}

/* Preview Section */
.preview-section {
    display: flex;
    flex-direction: column;
    background: #fff;
}

.preview-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 20px;
    background: #f8f9fa;
    border-bottom: 1px solid #e0e0e0;
    flex-wrap: wrap;
    gap: 10px;
}

.preview-actions {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

.action-btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 12px;
    background: #ecf0f1;
    color: #333;
    border: 1px solid #ccc;
    font-size: 0.85rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
}

.action-btn:hover {
    background: #3498db;
    color: #fff;
    border-color: #3498db;
}

#md-preview {
    flex: 1;
    padding: 20px;
    overflow-y: auto;
    background: #fff;
}

.placeholder-text {
    color: #999;
    font-style: italic;
}

/* Markdown Body Styles */
.markdown-body {
    font-size: 1rem;
    line-height: 1.8;
    color: #333;
}

.markdown-body h1 {
    font-size: 2rem;
    font-weight: 600;
    margin: 24px 0 16px;
    padding-bottom: 10px;
    border-bottom: 2px solid #eee;
    color: #2c3e50;
}

.markdown-body h2 {
    font-size: 1.5rem;
    font-weight: 600;
    margin: 20px 0 12px;
    padding-bottom: 8px;
    border-bottom: 1px solid #eee;
    color: #2c3e50;
}

.markdown-body h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin: 18px 0 10px;
    color: #2c3e50;
}

.markdown-body h4, .markdown-body h5, .markdown-body h6 {
    font-size: 1rem;
    font-weight: 600;
    margin: 16px 0 8px;
    color: #2c3e50;
}

.markdown-body p {
    margin: 0 0 16px;
}

.markdown-body a {
    color: #3498db;
    text-decoration: none;
}

.markdown-body a:hover {
    text-decoration: underline;
}

.markdown-body strong {
    font-weight: 600;
}

.markdown-body em {
    font-style: italic;
}

.markdown-body del {
    text-decoration: line-through;
    color: #999;
}

.markdown-body code {
    background: #f4f4f4;
    padding: 2px 6px;
    border-radius: 3px;
    font-family: "Consolas", "Monaco", monospace;
    font-size: 0.9em;
    color: #c0392b;
}

.markdown-body pre {
    background: #f8f8f8;
    border: 1px solid #e0e0e0;
    border-radius: 4px;
    padding: 16px;
    overflow-x: auto;
    margin: 0 0 16px;
}

.markdown-body pre code {
    background: none;
    padding: 0;
    color: inherit;
    font-size: 0.9rem;
    line-height: 1.5;
}

.markdown-body blockquote {
    border-left: 4px solid #3498db;
    padding: 10px 20px;
    margin: 0 0 16px;
    background: #f8f9fa;
    color: #555;
}

.markdown-body blockquote p {
    margin: 0;
}

.markdown-body ul, .markdown-body ol {
    margin: 0 0 16px;
    padding-left: 30px;
}

.markdown-body li {
    margin: 6px 0;
}

.markdown-body ul ul, .markdown-body ol ol, .markdown-body ul ol, .markdown-body ol ul {
    margin: 4px 0;
}

.markdown-body hr {
    border: none;
    border-top: 2px solid #eee;
    margin: 24px 0;
}

.markdown-body table {
    width: 100%;
    border-collapse: collapse;
    margin: 0 0 16px;
}

.markdown-body th, .markdown-body td {
    border: 1px solid #ddd;
    padding: 10px 12px;
    text-align: left;
}

.markdown-body th {
    background: #34495e;
    color: #fff;
    font-weight: 500;
}

.markdown-body tr:nth-child(even) {
    background: #f9f9f9;
}

.markdown-body img {
    max-width: 100%;
    height: auto;
    border-radius: 4px;
}

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

/* Notice Section */
.notice-section {
    background: #fffbe6;
    border: 1px solid #e6d8a8;
    border-left: 4px solid #d4a017;
    padding: 20px;
    margin: 0 30px 25px 30px;
}

.notice-section h2 {
    color: #5d4e00;
    margin-bottom: 12px;
    font-size: 1.1rem;
    border-bottom: none;
    padding-bottom: 0;
}

.syntax-guide {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 8px;
}

.syntax-row {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 6px 0;
}

.syntax-row code {
    background: #fff;
    padding: 4px 8px;
    border-radius: 3px;
    font-family: "Consolas", "Monaco", monospace;
    font-size: 0.85rem;
    color: #c0392b;
    border: 1px solid #e6d8a8;
    min-width: 120px;
}

.syntax-row span {
    color: #665500;
    font-size: 0.9rem;
}

/* Footer */
footer {
    background: #f8f9fa;
    text-align: center;
    padding: 15px 20px;
    color: #777;
    font-size: 0.85rem;
    border-top: 1px solid #ddd;
}

footer a {
    color: #3498db;
    text-decoration: none;
}

footer a:hover {
    text-decoration: underline;
}

/* Home Link */
.home-link {
    display: inline-block;
    color: #ecf0f1;
    text-decoration: none;
    font-size: 0.95rem;
    margin-bottom: 15px;
    opacity: 0.8;
    transition: opacity 0.2s;
    font-weight: 500;
}

.home-link:hover {
    opacity: 1;
    color: #fff;
}

/* Toast */
.toast {
    position: fixed;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background: #2c3e50;
    color: #fff;
    padding: 12px 24px;
    border-radius: 4px;
    font-size: 0.9rem;
    opacity: 0;
    transition: all 0.3s ease;
    z-index: 1000;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
}

.toast.show {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
}

/* Responsive */
@media (max-width: 900px) {
    main {
        grid-template-columns: 1fr;
    }

    .editor-section {
        border-right: none;
        border-bottom: 1px solid #ddd;
    }

    #md-input {
        min-height: 250px;
    }

    #md-preview {
        min-height: 300px;
    }
}

@media (max-width: 768px) {
    body {
        padding: 10px;
    }

    h1 {
        font-size: 1.3rem;
    }

    header {
        padding: 20px;
    }

    .editor-header, .preview-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .editor-actions, .preview-actions {
        width: 100%;
        justify-content: flex-start;
    }

    .notice-section {
        margin: 0 15px 20px 15px;
    }

    .syntax-guide {
        grid-template-columns: 1fr;
    }

    .syntax-row code {
        min-width: 100px;
    }
}

@media (max-width: 480px) {
    .file-label, .sample-btn, .clear-btn, .action-btn {
        padding: 6px 10px;
        font-size: 0.8rem;
    }

    #md-input, #md-preview {
        padding: 15px;
    }

    .markdown-body {
        font-size: 0.95rem;
    }

    .markdown-body h1 {
        font-size: 1.5rem;
    }

    .markdown-body h2 {
        font-size: 1.25rem;
    }
}