/* Root Variables - Simple and Clean */
:root {
    /* Primary Colors */
    --primary-color: #2196f3;
    --primary-hover: #1976d2;

    /* Accent Colors */
    --success-color: #4caf50;
    --warning-color: #ff9800;
    --danger-color: #f44336;
    --info-color: #00bcd4;

    /* Neutral Colors */
    --dark-bg: #263238;
    --sidebar-bg: #37474f;
    --card-bg: #ffffff;
    --light-gray: #f5f5f5;
    --border-color: #e0e0e0;
    --body-bg: #fafafa;

    /* Text Colors */
    --text-primary: #212121;
    --text-secondary: #757575;
    --text-white: #ffffff;

    /* Layout */
    --sidebar-width: 240px;
    --header-height: 60px;
    --footer-height: 50px;
    --border-radius: 4px;

    /* Shadows - Simplified */
    --shadow: 0 2px 4px rgba(0,0,0,0.1);
    --shadow-hover: 0 4px 8px rgba(0,0,0,0.15);
}

/* Dark Mode Variables */
body.dark-mode {
    --dark-bg: #1a1a1a;
    --sidebar-bg: #242424;
    --card-bg: #2d2d2d;
    --light-gray: #1f1f1f;
    --border-color: #404040;
    --body-bg: #121212;

    --text-primary: #e0e0e0;
    --text-secondary: #b0b0b0;
    --text-white: #ffffff;

    --shadow: 0 2px 4px rgba(0,0,0,0.3);
    --shadow-hover: 0 4px 8px rgba(0,0,0,0.4);
}

/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    height: 100vh;
    overflow: hidden;
    display: flex;
    background: var(--body-bg);
    padding-top: var(--header-height);
    padding-bottom: var(--footer-height);
    color: var(--text-primary);
    line-height: 1.5;
    font-size: 14px;
    transition: background-color 0.3s ease, color 0.3s ease;
}

/* Fixed Header - Simple */
.main-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--header-height);
    background: var(--primary-color);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    box-shadow: var(--shadow);
}

.main-header h1 {
    color: var(--text-white);
    font-size: 24px;
    font-weight: 600;
    letter-spacing: 0.5px;
    margin: 0;
}

/* Welcome/About styling */
.about-section {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-left: 6px solid var(--primary-color);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    padding: 20px 22px;
    animation: fadeInUp 0.35s ease both;
}

.about-section h3 {
    margin: 0 0 10px 0;
    font-size: 22px;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: 0.2px;
}

.about-section p {
    margin: 6px 0 14px 0;
    color: var(--text-secondary);
    font-size: 14px;
}

.about-section ul {
    list-style: none;
    margin: 0;
    padding: 0;
    display: grid;
    grid-template-columns: 1fr;
    gap: 12px;
}

@media (min-width: 700px) {
    .about-section ul {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (min-width: 900px) {
    .about-section ul {
        grid-template-columns: repeat(3, 1fr);
    }
}

.about-section li {
    display: flex;
    align-items: center; /* center content vertically to reduce bottom gap */
    gap: 10px;
    color: var(--text-primary);
    font-size: 14px;
    line-height: 1.45;
    padding: 8px 10px; /* less padding */
    border: 1px solid var(--border-color);
    border-radius: 10px;
    background: var(--light-gray);
    transition: background 0.25s ease, border-color 0.25s ease, transform 0.15s ease;
    min-height: 100px; /* tighter cube height */
}

.about-section li:hover {
    background: #eef6ff;
    border-color: var(--primary-color);
    transform: translateY(-1px);
}

body.dark-mode .about-section li:hover {
    background: #1f2633;
}

.about-section li::before {
    content: '';
    display: inline-block;
    width: 18px;
    height: 18px;
    margin-top: 0; /* center the dot with text */
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-hover));
    box-shadow: 0 0 0 2px rgba(33, 150, 243, 0.15);
    flex: 0 0 18px;
}

.try-section {
    background: transparent;
}

.try-section .tool-title-section {
    border-left: 4px solid var(--primary-color);
}

.try-section .tool-function-window {
    padding: 0;
    background: transparent;
    box-shadow: none;
}

.try-section .tool-function-window .tool-content {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    padding: 16px;
}

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(6px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Tool info panel */
.tool-info {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    padding: 16px 18px;
    margin-bottom: 12px;
}
.tool-info h3 {
    margin: 0 0 8px 0;
    font-size: 18px;
    color: var(--text-primary);
}
.tool-info p {
    margin: 6px 0 10px 0;
    color: var(--text-secondary);
    font-size: 14px;
}
.tool-info h4 {
    margin: 10px 0 6px 0;
    font-size: 15px;
    color: var(--text-primary);
}
.tool-info ul {
    margin: 0;
    padding-left: 18px;
    color: var(--text-primary);
    font-size: 14px;
}

/* Header links (About, Privacy) */
.header-links {
    position: absolute;
    right: 20px;
    display: flex;
    gap: 16px;
    align-items: center;
}

.header-link {
    color: rgba(255,255,255,0.9);
    text-decoration: none;
    font-size: 14px;
}

.header-link:hover {
    text-decoration: underline;
}

/* Dark Mode Toggle */
.dark-mode-toggle {
    position: absolute;
    right: 20px;
    background: rgba(255, 255, 255, 0.2);
    border: none;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.3s ease;
}

.dark-mode-toggle:hover {
    background: rgba(255, 255, 255, 0.3);
}

.dark-mode-toggle svg {
    width: 24px;
    height: 24px;
    fill: white;
}

/* Sidebar Styles - Simple */
.sidebar {
    width: var(--sidebar-width);
    background: var(--sidebar-bg);
    height: calc(100vh - var(--header-height) - var(--footer-height));
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    position: fixed;
    left: 0;
    top: var(--header-height);
    z-index: 100;
    transition: transform 0.3s, background-color 0.3s, box-shadow 0.3s;
    box-shadow: var(--shadow);
}

.sidebar-nav {
    flex: 1;
    padding: 16px 0;
}

.sidebar-search {
    position: sticky;
    top: 0;
    z-index: 2;
    background: var(--sidebar-bg);
    padding: 12px 16px 8px 16px;
    box-shadow: 0 1px 0 rgba(0,0,0,0.1);
}

.sidebar-search-input {
    width: 100%;
    height: 34px;
    border-radius: 6px;
    border: 1px solid rgba(255,255,255,0.25);
    background: rgba(255,255,255,0.08);
    color: var(--text-white);
    padding: 0 10px;
    outline: none;
    transition: border-color 0.2s ease, background 0.2s ease;
}

.sidebar-search-input::placeholder {
    color: rgba(255,255,255,0.7);
}

.sidebar-search-input:focus {
    border-color: var(--text-white);
    background: rgba(255,255,255,0.15);
}

.sidebar-nav ul {
    list-style: none;
}

.sidebar-nav li {
    margin-bottom: 2px;
}

.sidebar-nav a {
    display: block;
    padding: 12px 20px;
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    font-size: 14px;
    transition: background 0.2s, color 0.2s;
}

.sidebar-nav a:hover {
    background: rgba(255, 255, 255, 0.1);
    color: var(--text-white);
}

.sidebar-nav a.active {
    background: var(--primary-color);
    color: var(--text-white);
    border-left: 4px solid var(--text-white);
}

/* Scrollbar Styling for Sidebar - Modern */
.sidebar::-webkit-scrollbar {
    width: 6px;
}

.sidebar::-webkit-scrollbar-track {
    background: transparent;
}

.sidebar::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.2);
    border-radius: 3px;
}

.sidebar::-webkit-scrollbar-thumb:hover {
    background: rgba(255, 255, 255, 0.3);
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
    display: none;
    position: fixed;
    top: 20px;
    left: 20px;
    z-index: 1100;
    background-color: var(--primary-color);
    border: none;
    width: 40px;
    height: 40px;
    flex-direction: column;
    justify-content: space-around;
    padding: 8px;
    cursor: pointer;
    border-radius: 5px;
}

.mobile-menu-toggle span {
    width: 100%;
    height: 3px;
    background-color: var(--text-white);
    border-radius: 2px;
    transition: all 0.3s ease;
}

/* Main Content Area - Simple */
.main-content {
    margin-left: var(--sidebar-width);
    flex: 1;
    display: flex;
    flex-direction: column;
    height: calc(100vh - var(--header-height) - var(--footer-height));
    padding: 24px;
    gap: 16px;
    overflow-y: auto;
}

/* Tool Title Section - Simple */
.tool-title-section {
    background: var(--card-bg);
    padding: 16px 20px;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    border-left: 4px solid var(--primary-color);
    transition: background-color 0.3s, box-shadow 0.3s;
}

.tool-title {
    color: var(--text-primary);
    font-size: 20px;
    font-weight: 600;
    margin: 0;
    transition: color 0.3s;
}

/* Tool Function Window - Simple */
.tool-function-window {
    flex: 1;
    background: var(--card-bg);
    border-radius: var(--border-radius);
    padding: 24px;
    box-shadow: var(--shadow);
    overflow-y: auto;
    min-height: 400px;
    transition: background-color 0.3s, box-shadow 0.3s;
}

.tool-content {
    color: var(--text-primary);
    transition: color 0.3s;
}

.tool-content h2 {
    font-size: 18px;
    margin-bottom: 16px;
    font-weight: 600;
    color: var(--text-primary);
}

.tool-content h3 {
    font-size: 16px;
    margin-bottom: 12px;
    margin-top: 20px;
    font-weight: 600;
    color: var(--text-primary);
}

.tool-content p {
    font-size: 14px;
    line-height: 1.6;
    color: var(--text-secondary);
}

.tool-content label {
    font-size: 13px;
    font-weight: 600;
    color: var(--text-primary);
}

/* Tool Controls and Interface Styling - Simple */
.tool-controls {
    display: flex;
    gap: 8px;
    margin-bottom: 20px;
    flex-wrap: wrap;
}

.btn {
    padding: 8px 16px;
    font-size: 14px;
    font-weight: 500;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: background 0.2s, box-shadow 0.2s;
}

.btn-encode,
.btn-decode {
    background: var(--primary-color);
    color: white;
}

.btn-encode:hover,
.btn-decode:hover {
    background: var(--primary-hover);
}

.btn-clear {
    background: var(--light-gray);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    transition: background-color 0.2s, border-color 0.3s, color 0.3s;
}

.btn-clear:hover {
    background: var(--border-color);
}

.textarea-group {
    margin-bottom: 20px;
}

.textarea-group label {
    display: block;
    font-size: 13px;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--text-primary);
}

.tool-textarea {
    width: 100%;
    padding: 12px;
    font-size: 13px;
    font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    background-color: var(--light-gray);
    color: var(--text-primary);
    resize: vertical;
    min-height: 120px;
    transition: border-color 0.2s, background-color 0.3s, color 0.3s;
    line-height: 1.5;
}

.tool-textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    background-color: var(--card-bg);
}

.output-textarea {
    background-color: var(--light-gray);
    cursor: default;
}

/* Ad Space - Simple */
.ad-space {
    background: #f5f5f5;
    border: 1px dashed #ccc;
    border-radius: var(--border-radius);
    padding: 16px;
    min-height: 80px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.ad-placeholder {
    color: #999;
    font-size: 13px;
}

/* Responsive Design - Tablet */
@media (max-width: 1024px) {
    :root {
        --sidebar-width: 180px;
    }

    .main-content {
        padding: 20px;
    }

    .tool-function-window {
        padding: 30px;
    }
}

/* Responsive Design - Mobile */
@media (max-width: 768px) {
    .mobile-menu-toggle {
        display: flex;
    }

    .main-header h1 {
        font-size: 24px;
        letter-spacing: -0.3px;
    }

    .sidebar {
        transform: translateX(-100%);
        box-shadow: none;
    }

    .sidebar.active {
        transform: translateX(0);
        box-shadow: var(--shadow-xl);
    }

    .main-content {
        margin-left: 0;
        padding: 20px 16px;
    }

    .tool-title-section {
        padding: 16px 20px;
    }

    .tool-title {
        font-size: 18px;
    }

    .tool-function-window {
        padding: 24px 20px;
    }

    .tool-content h2 {
        font-size: 20px;
    }

    .tool-content h3 {
        font-size: 16px;
    }

    .tool-content p {
        font-size: 14px;
    }

    .tool-controls {
        gap: 8px;
    }

    .btn {
        padding: 10px 16px;
        font-size: 13px;
    }
}

/* Small Mobile */
@media (max-width: 480px) {
    .main-header h1 {
        font-size: 20px;
        letter-spacing: 0;
    }

    .sidebar-nav a {
        padding: 10px 14px;
        font-size: 13px;
    }

    .tool-title {
        font-size: 16px;
    }

    .tool-title::before {
        height: 20px;
    }

    .tool-function-window {
        padding: 20px 16px;
        min-height: 300px;
    }

    .ad-space {
        min-height: 80px;
    }

    .options-group {
        padding: 16px;
        gap: 12px;
    }

    .tool-textarea {
        padding: 12px;
        font-size: 13px;
    }
}

/* Animation for tool content changes - Simple */
.tool-content {
    animation: fadeIn 0.3s ease;
}

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

/* Main content scrollbar */
.main-content::-webkit-scrollbar {
    width: 8px;
}

.main-content::-webkit-scrollbar-track {
    background: #f5f5f5;
}

.main-content::-webkit-scrollbar-thumb {
    background: #ccc;
    border-radius: 4px;
}

.main-content::-webkit-scrollbar-thumb:hover {
    background: #999;
}

/* Enhanced Tool Styles */

/* Options Group - Simple */
.options-group {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    align-items: center;
    margin-bottom: 20px;
    padding: 16px;
    background: var(--light-gray);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    transition: background-color 0.3s, border-color 0.3s;
}

.options-group label {
    color: var(--text-primary);
    font-weight: 500;
    font-size: 13px;
}

.option-label {
    display: flex;
    align-items: center;
    gap: 8px;
    cursor: pointer;
    user-select: none;
}

.option-label input[type="checkbox"] {
    width: 18px;
    height: 18px;
    cursor: pointer;
}


/* Number Input - Simple */
.number-input,
.text-input,
.tool-input {
    padding: 8px 12px;
    border-radius: var(--border-radius);
    border: 1px solid var(--border-color);
    background-color: var(--card-bg);
    color: var(--text-primary);
    font-size: 13px;
    width: 100px;
    transition: border-color 0.2s, background-color 0.3s;
}

.number-input:focus,
.text-input:focus,
.tool-input:focus {
    outline: none;
    border-color: var(--primary-color);
}

.text-input,
.tool-input {
    width: 200px;
}

select,
select.select-input {
    padding: 8px 12px;
    border-radius: var(--border-radius);
    border: 1px solid var(--border-color);
    background-color: var(--card-bg);
    color: var(--text-primary);
    font-size: 13px;
    cursor: pointer;
    transition: border-color 0.2s, background-color 0.3s;
}

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

/* Range Input - Simple */
.range-input {
    width: 200px;
    height: 4px;
    border-radius: 2px;
    background: #ddd;
    outline: none;
    cursor: pointer;
    -webkit-appearance: none;
}

.range-input::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
}

.range-input::-webkit-slider-thumb:hover {
    background: var(--primary-hover);
}

.range-value {
    display: inline-block;
    min-width: 40px;
    padding: 4px 8px;
    background: var(--primary-color);
    color: white;
    border-radius: var(--border-radius);
    font-weight: 600;
    text-align: center;
    font-size: 12px;
}

/* Color Input */
.color-input {
    width: 60px;
    height: 40px;
    border-radius: 6px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    cursor: pointer;
}

/* Button Variations - Simple */
.btn-primary {
    background: var(--primary-color);
    color: white;
}

.btn-primary:hover {
    background: var(--primary-hover);
}

.btn-secondary {
    background: #9e9e9e;
    color: white;
}

.btn-secondary:hover {
    background: #757575;
}

.btn-copy {
    background: var(--primary-color);
    color: white;
}

.btn-copy:hover {
    background: var(--primary-hover);
}

.btn-mini {
    padding: 6px 12px;
    font-size: 13px;
    border-radius: var(--border-radius);
    border: none;
    cursor: pointer;
    transition: background 0.2s;
    font-weight: 500;
    background: var(--primary-color);
    color: white;
}

.btn-mini:hover {
    background: var(--primary-hover);
}

/* Validation Status - Simple */
.validation-status {
    margin-top: 12px;
    padding: 12px 16px;
    border-radius: var(--border-radius);
    font-size: 13px;
    border-left: 3px solid;
}

.validation-status .success {
    color: var(--success-color);
    border-color: var(--success-color);
    background: #e8f5e9;
}

.validation-status .error {
    color: var(--danger-color);
    border-color: var(--danger-color);
    background: #ffebee;
}

.validation-status .warning {
    color: #f57c00;
    border-color: var(--warning-color);
    background: #fff3e0;
}

.json-info {
    margin-top: 10px;
    padding: 12px;
    background-color: #f5f5f5;
    border-radius: var(--border-radius);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    font-size: 13px;
    line-height: 1.6;
}

/* Split View (for Markdown Preview) */
.split-view {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.split-panel {
    display: flex;
    flex-direction: column;
}

.split-panel label {
    color: var(--text-primary);
    font-weight: 600;
    margin-bottom: 10px;
}

.markdown-preview {
    background-color: var(--card-bg);
    padding: 24px;
    border-radius: var(--border-radius);
    border: 1px solid var(--border-color);
    min-height: 400px;
    overflow-y: auto;
    color: var(--text-primary);
    line-height: 1.8;
}

.markdown-preview h1,
.markdown-preview h2,
.markdown-preview h3 {
    margin-top: 1.2em;
    margin-bottom: 0.6em;
    color: var(--text-primary);
    font-weight: 700;
}

.markdown-preview h1 {
    font-size: 28px;
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 8px;
}

.markdown-preview h2 {
    font-size: 22px;
}

.markdown-preview h3 {
    font-size: 18px;
}

.markdown-preview code {
    background-color: var(--light-gray);
    color: var(--danger-color);
    padding: 3px 8px;
    border-radius: 4px;
    font-family: 'JetBrains Mono', 'Consolas', 'Monaco', monospace;
    font-size: 13px;
}

.markdown-preview pre {
    background-color: var(--darker-bg);
    color: var(--text-white);
    padding: 16px;
    border-radius: var(--border-radius-sm);
    overflow-x: auto;
    border: 1px solid var(--dark-bg);
}

.markdown-preview pre code {
    background: none;
    color: inherit;
    padding: 0;
}

.markdown-preview a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
    border-bottom: 2px solid transparent;
    transition: border-color var(--transition-fast);
}

.markdown-preview a:hover {
    border-bottom-color: var(--primary-color);
}

.markdown-preview .placeholder,
.markdown-preview .error {
    color: var(--text-light);
    font-style: italic;
}

/* Diff Checker Styles - Modern Code Diff */
.diff-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin-bottom: 24px;
}

.diff-input-section {
    display: flex;
    flex-direction: column;
}

.diff-input-section label {
    color: var(--text-primary);
    font-weight: 600;
    margin-bottom: 10px;
}

.diff-output {
    background-color: var(--card-bg);
    padding: 24px;
    border-radius: var(--border-radius);
    border: 1px solid var(--border-color);
    overflow-x: auto;
    max-height: 600px;
    overflow-y: auto;
    box-shadow: var(--shadow-sm);
}

.diff-stats {
    display: flex;
    gap: 20px;
    margin-bottom: 15px;
    padding-bottom: 15px;
    border-bottom: 2px solid #ddd;
}

.stat-item {
    font-size: 14px;
    color: #333;
}

.diff-side-by-side {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 10px;
}

.diff-column h4 {
    margin-bottom: 10px;
    color: #001f54;
}

.diff-line {
    display: flex;
    font-family: 'Consolas', 'Monaco', monospace;
    font-size: 13px;
    padding: 2px 0;
}

.line-num {
    display: inline-block;
    min-width: 40px;
    padding: 0 8px;
    color: #999;
    text-align: right;
    user-select: none;
}

.line-text {
    flex: 1;
    padding: 0 8px;
    white-space: pre-wrap;
    word-break: break-all;
}

.diff-delete {
    background-color: #ffebee;
}

.diff-insert {
    background-color: #e8f5e9;
}

.diff-change {
    background-color: #fff3e0;
}

.diff-empty {
    background-color: #fafafa;
}

/* Color Picker Styles */
.color-picker-container {
    display: flex;
    gap: 20px;
    align-items: center;
    margin-bottom: 20px;
}

.color-input-section {
    flex: 1;
}

.color-picker-large {
    width: 150px;
    height: 150px;
    border-radius: 8px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    cursor: pointer;
}

.color-preview {
    width: 150px;
    height: 150px;
    border-radius: 8px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
}

.color-formats {
    display: grid;
    gap: 15px;
}

.format-group {
    display: flex;
    align-items: center;
    gap: 10px;
}

.format-group label {
    min-width: 60px;
    color: var(--white);
    font-weight: 600;
}

.format-group input {
    flex: 1;
}

.color-harmonies {
    margin-top: 30px;
    padding: 20px;
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 8px;
}

.color-harmonies h3 {
    color: var(--white);
    margin-bottom: 15px;
}

.harmony-display {
    margin-top: 15px;
}

.harmony-colors {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.harmony-color {
    width: 100px;
    height: 100px;
    border-radius: 8px;
    display: flex;
    align-items: flex-end;
    justify-content: center;
    padding: 10px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}

.harmony-hex {
    background-color: rgba(0, 0, 0, 0.7);
    color: white;
    padding: 4px 8px;
    border-radius: 4px;
    font-size: 12px;
    font-family: 'Consolas', monospace;
}

/* QR Code Styles */
.qr-output-container {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 30px;
    background-color: rgba(255, 255, 255, 0.95);
    border-radius: 8px;
    min-height: 300px;
}

.qr-canvas {
    border: 2px solid #ddd;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.qr-placeholder {
    color: #999;
    font-size: 18px;
    font-style: italic;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
    height: 100%;
}

/* Password Strength */
.password-strength {
    margin-top: 15px;
    padding: 15px;
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    color: var(--white);
    font-size: 14px;
}

/* JWT Decoder Styles */
.jwt-output {
    display: grid;
    gap: 20px;
    margin-top: 20px;
}

.jwt-section h3 {
    color: var(--white);
    margin-bottom: 10px;
    font-size: 18px;
}

.jwt-display {
    background-color: rgba(255, 255, 255, 0.95);
    padding: 15px;
    border-radius: 8px;
    font-family: 'Consolas', 'Monaco', monospace;
    font-size: 13px;
    color: #333;
    overflow-x: auto;
    white-space: pre-wrap;
    word-break: break-all;
    min-height: 60px;
}

.jwt-info {
    color: var(--white);
    line-height: 1.8;
}

.timestamp-validation {
    margin-top: 10px;
    padding: 10px;
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 6px;
}

/* Error Message Styles */
.error-message {
    background-color: #ffebee;
    border-left: 4px solid #f44336;
    padding: 15px;
    border-radius: 6px;
    margin: 10px 0;
    color: #333;
}

.error-detail {
    display: block;
    margin-top: 8px;
    color: #666;
}

.error-details {
    margin-top: 10px;
    cursor: pointer;
}

.error-details summary {
    font-weight: 600;
    color: #0d47a1;
    padding: 5px 0;
}

.error-details summary:hover {
    text-decoration: underline;
}

.error-tech-info {
    background-color: #f5f5f5;
    padding: 10px;
    border-radius: 4px;
    margin-top: 8px;
    font-family: 'Consolas', 'Monaco', monospace;
    font-size: 12px;
}

.error-tech-info p {
    margin: 5px 0;
}

/* Footer Styles */
.main-footer {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    height: var(--footer-height);
    background: var(--sidebar-bg);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 30px;
    z-index: 1000;
    box-shadow: 0 -2px 4px rgba(0,0,0,0.1);
    transition: background-color 0.3s ease;
}

.footer-left,
.footer-right {
    display: flex;
    align-items: center;
    gap: 20px;
}

.footer-left {
    color: rgba(255, 255, 255, 0.8);
    font-size: 13px;
}

.footer-links {
    display: flex;
    gap: 20px;
}

.footer-links a {
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    font-size: 13px;
    transition: color 0.2s;
    display: flex;
    align-items: center;
    gap: 6px;
}

.footer-links a:hover {
    color: var(--text-white);
}

.footer-links svg {
    width: 16px;
    height: 16px;
    fill: currentColor;
}

/* HTML Viewer Styles */
.html-viewer-container {
    display: flex;
    gap: 16px;
    height: calc(100vh - 350px);
    min-height: 600px;
}

.html-viewer-container.horizontal {
    flex-direction: row;
}

.html-viewer-container.vertical {
    flex-direction: column;
}

.html-viewer-container.tabs .html-viewer-editors {
    position: relative;
}

.html-viewer-editors {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 12px;
    overflow-y: auto;
}

.html-viewer-container.horizontal .html-viewer-editors {
    flex: 0 0 50%;
}

.html-viewer-container.vertical .html-viewer-editors {
    flex: 0 0 60%;
}

.html-viewer-editor-section {
    display: flex;
    flex-direction: column;
    min-height: 200px;
}

.html-viewer-editor-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px 12px;
    background: var(--primary-color);
    color: white;
    border-radius: var(--border-radius) var(--border-radius) 0 0;
    font-weight: 600;
    font-size: 13px;
}

.editor-label {
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.html-viewer-textarea {
    flex: 1;
    width: 100%;
    padding: 12px;
    font-size: 13px;
    font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
    border: 1px solid var(--border-color);
    border-top: none;
    border-radius: 0 0 var(--border-radius) var(--border-radius);
    background-color: var(--card-bg);
    color: var(--text-primary);
    resize: vertical;
    min-height: 150px;
    line-height: 1.5;
    transition: background-color 0.3s, color 0.3s, border-color 0.3s;
}

.html-viewer-textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(33, 150, 243, 0.1);
}

.html-viewer-preview-section {
    flex: 1;
    display: flex;
    flex-direction: column;
}

.html-viewer-container.horizontal .html-viewer-preview-section {
    flex: 0 0 50%;
}

.html-viewer-container.vertical .html-viewer-preview-section {
    flex: 0 0 40%;
}

.html-viewer-preview-container {
    flex: 1;
    background: white;
    border: 1px solid var(--border-color);
    border-top: none;
    border-radius: 0 0 var(--border-radius) var(--border-radius);
    overflow: hidden;
}

.html-viewer-preview {
    width: 100%;
    height: 100%;
    border: none;
    background: white;
}

/* Accessibility utility */
.visually-hidden {
    position: absolute !important;
    height: 1px; width: 1px;
    overflow: hidden;
    clip: rect(1px, 1px, 1px, 1px);
    white-space: nowrap; /* added line */
}

/* Responsive adjustments for new styles */
@media (max-width: 768px) {
    .split-view,
    .diff-container,
    .diff-side-by-side {
        grid-template-columns: 1fr;
    }

    .color-picker-container {
        flex-direction: column;
    }

    .options-group {
        flex-direction: column;
        align-items: flex-start;
    }

    .range-input {
        width: 100%;
    }

    .main-footer {
        padding: 0 16px;
        flex-direction: column;
        height: auto;
        padding: 10px 16px;
        gap: 8px;
    }

    .footer-left,
    .footer-right {
        font-size: 12px;
        gap: 12px;
    }

    .footer-links {
        gap: 12px;
    }

    .dark-mode-toggle {
        width: 36px;
        height: 36px;
    }

    .dark-mode-toggle svg {
        width: 20px;
        height: 20px;
    }

    .html-viewer-container,
    .html-viewer-container.horizontal {
        flex-direction: column;
        height: auto;
    }

    .html-viewer-container .html-viewer-editors,
    .html-viewer-container .html-viewer-preview-section {
        flex: 1 1 auto;
    }

    .html-viewer-editor-section {
        min-height: 150px;
    }

    .html-viewer-preview-container {
        min-height: 300px;
    }
}