/**
 * AI Trading Bot ROI Calculator - Complete CSS Stylesheet
 * 
 * @package AI_ROI_Calculator
 * @version 1.0.0
 */

/* ================================================================
   GENERAL STYLES & RESET
   ================================================================ */

* {
    box-sizing: border-box;
}

/* ================================================================
   MAIN CONTAINER
   ================================================================ */
.calculator-help-section {
    display: none; /* Ẩn phần hướng dẫn */
}
.roi-calculator-pro {
    max-width: 1200px;
    margin: 40px auto;
    padding: 30px;
    background: #ffffff;
    border-radius: 15px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
}

.roi-calculator-pro h2 {
    text-align: center;
    color: #2d3748;
    margin: 0 0 10px 0;
    font-size: 32px;
    font-weight: 700;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.calculator-subtitle {
    text-align: center;
    color: #718096;
    font-size: 16px;
    margin: 0 0 35px 0;
    font-weight: 500;
}

/* ================================================================
   HELP SECTION - PROFESSIONAL GUIDE
   ================================================================ */

.calculator-help-section {
    margin-bottom: 40px;
    background: linear-gradient(135deg, #f0f4ff 0%, #f5f0ff 100%);
    border-radius: 12px;
    border: 2px solid #e0e7ff;
    overflow: hidden;
}

.help-container {
    background: white;
    border-radius: 10px;
    margin: 2px;
}

.help-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 25px 30px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    cursor: pointer;
    user-select: none;
    gap: 20px;
}

.help-header-content {
    flex: 1;
}

.help-header h3 {
    margin: 0 0 8px 0;
    font-size: 20px;
    font-weight: 700;
    letter-spacing: 0.3px;
}

.help-subtitle {
    margin: 0;
    font-size: 14px;
    opacity: 0.95;
    font-weight: 500;
}

.help-toggle {
    background: rgba(255, 255, 255, 0.2);
    border: 2px solid rgba(255, 255, 255, 0.3);
    color: white;
    font-size: 20px;
    cursor: pointer;
    padding: 10px 15px;
    border-radius: 8px;
    transition: all 0.3s ease;
    flex-shrink: 0;
}

.help-toggle:hover {
    background: rgba(255, 255, 255, 0.3);
    border-color: rgba(255, 255, 255, 0.5);
}

.help-toggle.active .help-toggle-icon {
    transform: rotate(180deg);
}

.help-toggle-icon {
    display: inline-block;
    transition: transform 0.3s ease;
}

.help-content {
    max-height: 2000px;
    overflow: hidden;
    animation: expandHeight 0.4s ease;
}

.help-content.collapsed {
    max-height: 0;
    overflow: hidden;
    animation: collapseHeight 0.4s ease;
}

@keyframes expandHeight {
    from {
        max-height: 0;
        opacity: 0;
    }
    to {
        max-height: 2000px;
        opacity: 1;
    }
}

@keyframes collapseHeight {
    from {
        max-height: 2000px;
        opacity: 1;
    }
    to {
        max-height: 0;
        opacity: 0;
    }
}

/* Help Steps Section */
.help-steps {
    padding: 35px 30px;
    border-bottom: 2px solid #e2e8f0;
}

.help-step {
    display: flex;
    gap: 25px;
    margin-bottom: 30px;
    padding: 25px;
    background: linear-gradient(135deg, #f6f8fb 0%, #faf9ff 100%);
    border-radius: 12px;
    border-left: 5px solid #667eea;
    transition: all 0.3s ease;
}

.help-step:hover {
    background: linear-gradient(135deg, #edf2f7 0%, #f0e8ff 100%);
    transform: translateX(8px);
    box-shadow: 0 8px 20px rgba(102, 126, 234, 0.15);
}

.help-step:last-child {
    margin-bottom: 0;
}

.step-number {
    min-width: 55px;
    width: 55px;
    height: 55px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-radius: 50%;
    font-weight: bold;
    font-size: 24px;
    flex-shrink: 0;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.3);
}

.step-content {
    flex: 1;
}

.step-content h4 {
    margin: 0 0 10px 0;
    color: #2d3748;
    font-size: 18px;
    font-weight: 700;
    letter-spacing: 0.3px;
}

.step-content p {
    margin: 0;
    color: #4a5568;
    font-size: 15px;
    line-height: 1.7;
}

/* Understanding Metrics Section */
.help-understanding {
    padding: 35px 30px;
    border-bottom: 2px solid #e2e8f0;
    background: linear-gradient(135deg, #f9f7ff 0%, #fff8f0 100%);
}

.help-understanding h4 {
    margin: 0 0 25px 0;
    color: #2d3748;
    font-size: 20px;
    font-weight: 700;
    letter-spacing: 0.3px;
}

.understanding-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
}

.metric-item {
    background: white;
    padding: 20px;
    border-radius: 10px;
    border-left: 4px solid #764ba2;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
}

.metric-item h5 {
    margin: 0 0 10px 0;
    color: #2d3748;
    font-size: 16px;
    font-weight: 600;
}

.metric-item p {
    margin: 0;
    color: #4a5568;
    font-size: 14px;
    line-height: 1.6;
}

/* FAQ Section */
.help-faq {
    padding: 35px 30px;
    border-bottom: 2px solid #e2e8f0;
}

.help-faq h4 {
    margin: 0 0 25px 0;
    color: #2d3748;
    font-size: 20px;
    font-weight: 700;
}

.faq-item {
    margin-bottom: 20px;
    padding: 20px;
    background: #f7fafc;
    border-radius: 10px;
    border-left: 4px solid #667eea;
    transition: all 0.3s ease;
}

.faq-item:hover {
    background: #edf2f7;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.1);
}

.faq-item:last-child {
    margin-bottom: 0;
}

.faq-question {
    color: #2d3748;
    font-size: 16px;
    margin: 0;
    padding: 10px 0;
    font-weight: 600;
    cursor: pointer;
}

.faq-question:hover {
    color: #667eea;
}

.faq-answer {
    display: block;
    margin-top: 12px;
    padding-top: 12px;
    border-top: 1px solid #e2e8f0;
    color: #4a5568;
    font-size: 15px;
    line-height: 1.7;
}

.faq-answer p {
    margin: 0;
}

/* Example Section */
.help-example {
    padding: 35px 30px;
    border-bottom: 2px solid #e2e8f0;
    background: linear-gradient(135deg, #fffbf0 0%, #f0f8ff 100%);
}

.help-example h4 {
    margin: 0 0 25px 0;
    color: #2d3748;
    font-size: 20px;
    font-weight: 700;
}

.example-content {
    display: flex;
    gap: 30px;
    align-items: stretch;
    margin-bottom: 20px;
}

.example-section {
    flex: 1;
    background: white;
    padding: 25px;
    border-radius: 10px;
    border: 2px solid #e2e8f0;
}

.example-section h5 {
    margin: 0 0 15px 0;
    color: #2d3748;
    font-size: 16px;
    font-weight: 700;
}

.example-section ul {
    margin: 0;
    padding-left: 20px;
    list-style: none;
}

.example-section li {
    margin-bottom: 12px;
    color: #4a5568;
    font-size: 15px;
    line-height: 1.6;
}

.example-section li:last-child {
    margin-bottom: 0;
}

.example-section strong {
    color: #667eea;
    font-weight: 600;
}

.example-arrow {
    display: flex;
    align-items: center;
    font-size: 28px;
    color: #667eea;
    font-weight: bold;
    min-width: 60px;
    justify-content: center;
}

.example-note {
    background: linear-gradient(135deg, #fef3c7 0%, #fde68a 100%);
    padding: 20px;
    border-radius: 10px;
    border-left: 4px solid #f59e0b;
}

.example-note p {
    margin: 0;
    color: #78350f;
    font-size: 15px;
    line-height: 1.7;
}

/* Pro Tips Section */
.help-tips {
    padding: 35px 30px;
}

.help-tips h4 {
    margin: 0 0 25px 0;
    color: #2d3748;
    font-size: 20px;
    font-weight: 700;
}

.help-tips ul {
    margin: 0;
    padding-left: 0;
    list-style: none;
}

.help-tips li {
    background: linear-gradient(135deg, #e0e7ff 0%, #f3e8ff 100%);
    padding: 18px 20px;
    margin-bottom: 15px;
    border-radius: 10px;
    border-left: 4px solid #667eea;
    color: #2d3748;
    font-size: 15px;
    line-height: 1.7;
    transition: all 0.3s ease;
}

.help-tips li:hover {
    background: linear-gradient(135deg, #cbd5e0 0%, #e9d5ff 100%);
    transform: translateX(5px);
}

.help-tips li:last-child {
    margin-bottom: 0;
}

.help-tips strong {
    color: #667eea;
    font-weight: 700;
}

/* ================================================================
   TABS NAVIGATION
   ================================================================ */

.calc-tabs {
    display: flex;
    gap: 10px;
    margin-bottom: 30px;
    border-bottom: 2px solid #e2e8f0;
    flex-wrap: wrap;
}

.calc-tab-btn {
    flex: 1;
    min-width: 120px;
    padding: 15px 20px;
    background: transparent;
    border: none;
    border-bottom: 3px solid transparent;
    cursor: pointer;
    font-size: 16px;
    font-weight: 600;
    color: #718096;
    transition: all 0.3s ease;
    white-space: nowrap;
}

.calc-tab-btn:hover {
    color: #667eea;
    background: rgba(102, 126, 234, 0.05);
}

.calc-tab-btn.active {
    color: #667eea;
    border-bottom-color: #667eea;
    background: rgba(102, 126, 234, 0.05);
}

/* ================================================================
   TAB CONTENT
   ================================================================ */

.calc-tab-content {
    display: none;
    animation: fadeIn 0.3s ease;
}

.calc-tab-content.active {
    display: block;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.tab-description {
    color: #718096;
    margin: 0 0 25px 0;
    font-size: 15px;
    padding: 18px 20px;
    background: linear-gradient(135deg, #f7fafc 0%, #edf2f7 100%);
    border-left: 4px solid #667eea;
    border-radius: 8px;
    font-weight: 500;
}

/* ================================================================
   FORM STYLES
   ================================================================ */

.calc-form {
    margin-bottom: 30px;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin-bottom: 20px;
}

.form-group {
    display: flex;
    flex-direction: column;
}

.form-group label {
    margin-bottom: 8px;
    font-weight: 600;
    color: #4a5568;
    font-size: 14px;
}

.required {
    color: #ef4444;
    font-weight: bold;
}

.form-group input {
    padding: 12px 15px;
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    font-size: 15px;
    transition: all 0.3s ease;
    font-family: inherit;
}

.form-group input:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.form-group input::placeholder {
    color: #a0aec0;
}

/* ================================================================
   BUTTONS
   ================================================================ */

.button-group {
    display: flex;
    gap: 15px;
    margin-top: 25px;
    flex-wrap: wrap;
}

.btn-primary,
.btn-secondary,
.btn-action {
    padding: 14px 28px;
    border: none;
    border-radius: 8px;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    white-space: nowrap;
    font-family: inherit;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    flex: 1;
    justify-content: center;
    min-width: 150px;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(102, 126, 234, 0.4);
}

.btn-primary:active {
    transform: translateY(0);
}

.btn-primary:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

.btn-secondary {
    background: #f7fafc;
    color: #4a5568;
    border: 2px solid #e2e8f0;
}

.btn-secondary:hover {
    background: #edf2f7;
    border-color: #cbd5e0;
}

.btn-action {
    background: white;
    color: #667eea;
    border: 2px solid #667eea;
    padding: 12px 24px;
}

.btn-action:hover {
    background: #667eea;
    color: white;
    box-shadow: 0 8px 20px rgba(102, 126, 234, 0.3);
    transform: translateY(-2px);
}

.icon {
    font-size: 18px;
}

/* ================================================================
   RESULTS SECTION - COLORFUL CARDS
   ================================================================ */

.results-section {
    margin-top: 40px;
    padding: 30px;
    background: linear-gradient(135deg, #f6f8fb 0%, #ffffff 100%);
    border-radius: 12px;
    border: 2px solid #e2e8f0;
    animation: slideIn 0.4s ease;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.results-section h3 {
    margin: 0 0 25px 0;
    color: #2d3748;
    font-size: 24px;
    font-weight: 700;
}

.results-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

/* Result Card Base Styles */
.result-card {
    background: white;
    padding: 28px;
    border-radius: 12px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
    transition: all 0.3s ease;
    border-top: 5px solid;
    position: relative;
    overflow: hidden;
}

.result-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.5) 0%, rgba(255, 255, 255, 0) 100%);
    pointer-events: none;
}

.result-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 12px 30px rgba(0, 0, 0, 0.12);
}

/* Net Profit Card - Green */
.result-card:nth-child(1) {
    border-top-color: #10b981;
}

.result-card:nth-child(1)::after {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    width: 100px;
    height: 100px;
    background: radial-gradient(circle, rgba(16, 185, 129, 0.1) 0%, transparent 70%);
    border-radius: 50%;
    pointer-events: none;
}

/* Total ROI Card - Purple (Highlight) */
.result-card.highlight {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-top-color: #5568d3;
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.3);
}

.result-card.highlight::after {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    width: 120px;
    height: 120px;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.2) 0%, transparent 70%);
    border-radius: 50%;
    pointer-events: none;
}

.result-card.highlight:hover {
    box-shadow: 0 15px 40px rgba(102, 126, 234, 0.4);
    transform: translateY(-10px) scale(1.02);
}

.result-card.highlight .result-label,
.result-card.highlight .result-value {
    color: white;
}

/* Monthly ROI Card - Orange */
.result-card:nth-child(3) {
    border-top-color: #f59e0b;
}

.result-card:nth-child(3)::after {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    width: 100px;
    height: 100px;
    background: radial-gradient(circle, rgba(245, 158, 11, 0.1) 0%, transparent 70%);
    border-radius: 50%;
    pointer-events: none;
}

/* Yearly ROI Card - Blue */
.result-card:nth-child(4) {
    border-top-color: #3b82f6;
}

.result-card:nth-child(4)::after {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    width: 100px;
    height: 100px;
    background: radial-gradient(circle, rgba(59, 130, 246, 0.1) 0%, transparent 70%);
    border-radius: 50%;
    pointer-events: none;
}

.result-label {
    font-size: 13px;
    color: #718096;
    margin-bottom: 8px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-weight: 600;
}

.result-value {
    font-size: 28px;
    font-weight: bold;
    color: #2d3748;
    position: relative;
    z-index: 1;
}

.result-value.positive {
    color: #10b981;
}

.result-value.negative {
    color: #ef4444;
}

.result-card.highlight .result-value.positive {
    color: #86efac;
}

.result-card.highlight .result-value.negative {
    color: #fca5a5;
}

/* Chart Container */
.chart-container {
    margin: 30px 0;
    padding: 25px;
    background: white;
    border-radius: 12px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
    border: 1px solid #e2e8f0;
}

.chart-container h4 {
    margin: 0 0 20px 0;
    color: #4a5568;
    font-size: 18px;
    font-weight: 600;
}

.chart-container canvas {
    max-height: 350px;
}

/* Result Actions */
.result-actions {
    display: flex;
    gap: 15px;
    margin-top: 25px;
    flex-wrap: wrap;
}

.btn-action {
    background: white;
    color: #667eea;
    border: 2px solid #667eea;
    padding: 12px 24px;
    border-radius: 8px;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    white-space: nowrap;
    font-family: inherit;
}

.btn-action:hover {
    background: #667eea;
    color: white;
    box-shadow: 0 8px 20px rgba(102, 126, 234, 0.3);
    transform: translateY(-2px);
}

/* ================================================================
   COMPARISON SECTION
   ================================================================ */

.compare-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.strategy-comparison-input {
    padding: 25px;
    background: #f7fafc;
    border-radius: 10px;
    border: 2px solid #e2e8f0;
    transition: all 0.3s ease;
}

.strategy-comparison-input:hover {
    border-color: #cbd5e0;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
}

.strategy-comparison-input h4 {
    margin: 0 0 15px 0;
    color: #4a5568;
    font-size: 16px;
    font-weight: 600;
}

.strategy-comparison-input input {
    width: 100%;
    padding: 12px 15px;
    margin-bottom: 12px;
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    font-size: 14px;
    font-family: inherit;
    transition: all 0.3s ease;
}

.strategy-comparison-input input:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.strategy-comparison-input input::placeholder {
    color: #a0aec0;
}

/* Comparison Table */
.comparison-table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 30px;
    background: white;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
}

.comparison-table thead {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.comparison-table th,
.comparison-table td {
    padding: 15px 20px;
    text-align: left;
}

.comparison-table th {
    font-weight: 600;
    font-size: 14px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.comparison-table tbody tr {
    border-bottom: 1px solid #e2e8f0;
    transition: background 0.2s ease;
}

.comparison-table tbody tr:hover {
    background: #f7fafc;
}

.comparison-table tbody tr:last-child {
    border-bottom: none;
}

.comparison-table .positive {
    color: #10b981;
    font-weight: bold;
}

.comparison-table .negative {
    color: #ef4444;
    font-weight: bold;
}

/* ================================================================
   HISTORY SECTION
   ================================================================ */

.history-container {
    margin-top: 25px;
}

.history-item {
    background: white;
    padding: 20px;
    margin-bottom: 15px;
    border-radius: 10px;
    border-left: 4px solid #667eea;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
    transition: all 0.3s ease;
}

.history-item:hover {
    transform: translateX(5px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.1);
}

.history-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 12px;
}

.history-header strong {
    color: #2d3748;
    font-size: 16px;
}

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

.btn-icon {
    background: transparent;
    border: none;
    cursor: pointer;
    font-size: 18px;
    padding: 5px;
    transition: transform 0.2s ease;
}

.btn-icon:hover {
    transform: scale(1.2);
}

.history-meta {
    margin-bottom: 10px;
}

.history-date {
    color: #718096;
    font-size: 13px;
}

.history-details {
    display: flex;
    gap: 20px;
    font-size: 14px;
    flex-wrap: wrap;
}

.history-details span {
    color: #4a5568;
}

.history-details .positive {
    color: #10b981;
    font-weight: bold;
}

.history-details .negative {
    color: #ef4444;
    font-weight: bold;
}

.no-history {
    text-align: center;
    color: #718096;
    padding: 40px 20px;
    font-style: italic;
    font-size: 15px;
}

/* ================================================================
   USAGE STATS
   ================================================================ */

.usage-stats {
    margin-top: 30px;
    text-align: center;
    padding: 15px;
    background: #f7fafc;
    border-radius: 8px;
}

.usage-stats small {
    color: #718096;
    font-size: 13px;
}

.usage-stats span {
    font-weight: bold;
    color: #667eea;
}

/* ================================================================
   RESPONSIVE DESIGN - TABLET
   ================================================================ */

@media (max-width: 768px) {
    .roi-calculator-pro {
        padding: 20px;
        margin: 20px auto;
    }
    
    .roi-calculator-pro h2 {
        font-size: 24px;
    }
    
    .calculator-subtitle {
        font-size: 14px;
    }
    
    .help-header {
        flex-direction: column;
        gap: 15px;
        text-align: center;
        padding: 20px;
    }
    
    .help-header h3 {
        font-size: 18px;
    }
    
    .help-steps {
        padding: 25px 20px;
    }
    
    .help-step {
        gap: 15px;
        padding: 20px;
        margin-bottom: 20px;
    }
    
    .step-number {
        min-width: 50px;
        width: 50px;
        height: 50px;
        font-size: 20px;
    }
    
    .example-content {
        flex-direction: column;
        gap: 20px;
    }
    
    .example-arrow {
        transform: rotate(90deg);
        margin: -10px 0;
    }
    
    .form-row {
        grid-template-columns: 1fr;
    }
    
    .results-grid {
        grid-template-columns: 1fr;
    }
    
    .button-group {
        flex-direction: column;
    }
    
    .btn-primary,
    .btn-secondary,
    .btn-action {
        width: 100%;
        justify-content: center;
    }
    
    .compare-container {
        grid-template-columns: 1fr;
    }
    
    .result-actions {
        flex-direction: column;
    }
    
    .calc-tabs {
        flex-direction: column;
    }
    
    .calc-tab-btn {
        width: 100%;
    }
    
    .comparison-table {
        font-size: 13px;
    }
    
    .comparison-table th,
    .comparison-table td {
        padding: 10px;
    }
    
    .understanding-content {
        grid-template-columns: 1fr;
    }
}

/* ================================================================
   RESPONSIVE DESIGN - MOBILE
   ================================================================ */

@media (max-width: 480px) {
    .roi-calculator-pro {
        padding: 15px;
    }
    
    .roi-calculator-pro h2 {
        font-size: 20px;
    }
    
    .calculator-subtitle {
        font-size: 13px;
        margin-bottom: 20px;
    }
    
    .help-content {
        max-height: 3000px;
    }
    
    .help-header {
        padding: 15px;
    }
    
    .help-header h3 {
        font-size: 16px;
    }
    
    .help-subtitle {
        font-size: 13px;
    }
    
    .step-number {
        min-width: 45px;
        width: 45px;
        height: 45px;
        font-size: 18px;
    }
    
    .step-content h4 {
        font-size: 16px;
    }
    
    .step-content p {
        font-size: 14px;
    }
    
    .result-card {
        padding: 18px;
    }
    
    .result-label {
        font-size: 12px;
    }
    
    .result-value {
        font-size: 22px;
    }
    
    .result-card.highlight {
        padding: 20px;
    }
    
    .chart-container {
        padding: 15px;
    }
    
    .chart-container canvas {
        max-height: 250px;
    }
    
    .form-row {
        grid-template-columns: 1fr;
        gap: 15px;
    }
    
    .results-grid {
        grid-template-columns: 1fr;
        gap: 15px;
    }
    
    .button-group {
        flex-direction: column;
        gap: 10px;
    }
    
    .btn-primary,
    .btn-secondary,
    .btn-action {
        font-size: 14px;
        padding: 12px 20px;
    }
    
    .compare-container {
        grid-template-columns: 1fr;
        gap: 15px;
    }
    
    .strategy-comparison-input {
        padding: 20px;
    }
    
    .comparison-table {
        font-size: 12px;
    }
    
    .comparison-table th,
    .comparison-table td {
        padding: 8px;
    }
    
    .tab-description {
        font-size: 14px;
        padding: 12px 15px;
    }
    
    .history-item {
        padding: 15px;
    }
    
    .history-details {
        gap: 15px;
        font-size: 13px;
    }
}

/* ================================================================
   PRINT STYLES
   ================================================================ */

@media print {
    .calc-tabs,
    .button-group,
    .result-actions,
    .usage-stats,
    .btn-icon,
    .help-header {
        display: none !important;
    }
    
    .roi-calculator-pro {
        box-shadow: none;
        padding: 0;
    }
    
    .results-section {
        border: 1px solid #000;
        page-break-inside: avoid;
    }
    
    .chart-container {
        page-break-inside: avoid;
    }
    
    .result-card {
        page-break-inside: avoid;
    }
}

/* ================================================================
   ACCESSIBILITY
   ================================================================ */

.calc-tab-btn:focus,
.btn-primary:focus,
.btn-secondary:focus,
.btn-action:focus,
input:focus {
    outline: 2px solid #667eea;
    outline-offset: 2px;
}

button:disabled {
    cursor: not-allowed;
    opacity: 0.5;
}

/* ================================================================
   DARK MODE SUPPORT (OPTIONAL)
   ================================================================ */

@media (prefers-color-scheme: dark) {
    .roi-calculator-pro {
        background: #1a202c;
        color: #e2e8f0;
    }
    
    .result-card {
        background: #2d3748;
    }
    
    .form-group input {
        background: #2d3748;
        color: #e2e8f0;
        border-color: #4a5568;
    }
    
    .help-step {
        background: linear-gradient(135deg, #2d3748 0%, #374151 100%);
    }
}