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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #000000;
    background: #ffffff;
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

/* Header Styles */
header {
    text-align: center;
    margin-bottom: 40px;
    background: #ffffff;
    padding: 30px;
    border: 1px solid #000000;
    border-radius: 0;
}

header h1 {
    font-size: 2.5rem;
    color: #000000;
    margin-bottom: 10px;
}

header p {
    font-size: 1.2rem;
    color: #000000;
}

/* Knowledge Section */
.knowledge-section {
    background: #ffffff;
    padding: 30px;
    border: 1px solid #000000;
    margin-bottom: 30px;
    border-radius: 0;
}

.knowledge-section h2 {
    color: #000000;
    margin-bottom: 25px;
    text-align: center;
    font-size: 1.8rem;
}

.knowledge-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 25px;
}

.knowledge-card {
    background: #ffffff;
    padding: 25px;
    border: 1px solid #000000;
    border-radius: 0;
}

.knowledge-card h3 {
    color: #000000;
    margin-bottom: 15px;
    font-size: 1.3rem;
}

.knowledge-card p {
    margin-bottom: 10px;
    color: #000000;
}

.knowledge-card strong {
    color: #000000;
}

/* Experiment Section */
.experiment-section {
    background: #ffffff;
    padding: 30px;
    border: 1px solid #000000;
    margin-bottom: 30px;
    border-radius: 0;
}

.experiment-section h2 {
    color: #000000;
    margin-bottom: 25px;
    text-align: center;
    font-size: 1.8rem;
}

.control-panel {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.control-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.control-group label {
    font-weight: 600;
    color: #000000;
    font-size: 0.95rem;
}

.control-group select,
.control-group input[type="range"] {
    padding: 10px;
    border: 1px solid #000000;
    border-radius: 0;
    font-size: 1rem;
    background: #ffffff;
    color: #000000;
}

.control-group select:focus,
.control-group input[type="range"]:focus {
    outline: none;
    border-color: #000000;
}

.control-group input[type="range"] {
    -webkit-appearance: none;
    height: 8px;
    background: #ffffff;
    border: 1px solid #000000;
    outline: none;
}

.control-group input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 20px;
    height: 20px;
    background: #000000;
    border: 1px solid #000000;
    cursor: pointer;
}

.control-group span {
    font-weight: 600;
    color: #000000;
    text-align: center;
    padding: 5px;
    background: #ffffff;
    border: 1px solid #000000;
}

/* Action Buttons */
.action-buttons {
    display: flex;
    justify-content: center;
    gap: 20px;
    flex-wrap: wrap;
}

.btn-primary, .btn-secondary, .btn-success {
    padding: 15px 30px;
    border: 1px solid #000000;
    border-radius: 0;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    text-transform: uppercase;
    letter-spacing: 1px;
    background: #ffffff;
    color: #000000;
}

.btn-primary:hover, .btn-secondary:hover, .btn-success:hover {
    background: #000000;
    color: #ffffff;
}

/* Results Section */
.results-section {
    background: #ffffff;
    padding: 30px;
    border: 1px solid #000000;
    margin-bottom: 30px;
    border-radius: 0;
}

.results-section h2 {
    color: #000000;
    margin-bottom: 25px;
    text-align: center;
    font-size: 1.8rem;
}

.results-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 15px;
    margin-bottom: 30px;
}

.result-card {
    background: #ffffff;
    padding: 20px 15px;
    border: 1px solid #000000;
    text-align: center;
    border-radius: 0;
    min-width: 0;
}

.result-card h3 {
    color: #000000;
    margin-bottom: 15px;
    font-size: 1.1rem;
}

/* Meter Styles */
.meter {
    width: 100%;
    height: 20px;
    background: #ffffff;
    border: 1px solid #000000;
    overflow: hidden;
    margin-bottom: 15px;
}

.meter-fill {
    height: 100%;
    background: #000000;
    transition: width 0.5s ease;
}

.quality-indicator {
    margin-bottom: 15px;
}

.quality-bar {
    width: 100%;
    height: 20px;
    background: #ffffff;
    border: 1px solid #000000;
    overflow: hidden;
    margin-bottom: 15px;
}

.quality-bar::before {
    content: '';
    display: block;
    height: 100%;
    width: 75%;
    background: #000000;
    transition: width 0.5s ease;
}

.interference-meter {
    width: 100%;
    height: 20px;
    background: #ffffff;
    border: 1px solid #000000;
    overflow: hidden;
    margin-bottom: 15px;
}

.interference-fill {
    height: 100%;
    background: #000000;
    transition: width 0.5s ease;
}

.speed-display p {
    margin-bottom: 10px;
    font-size: 1.1rem;
    color: #000000;
}

.speed-display span {
    font-weight: 600;
    color: #000000;
}

/* Real-time Graph */
.real-time-graph {
    text-align: center;
    padding: 20px; /* 전체 여백 조정 */
    margin-bottom: 40px; /* 다음 섹션과의 간격 유지 */
    overflow: hidden; /* 차트가 섹션을 벗어나지 않도록 */
}

.real-time-graph h3 {
    color: #000000;
    margin-bottom: 30px; /* 제목 아래 여백 증가 */
    font-size: 1.3rem;
}

#signalChart {
    position: relative;
    width: 1006px; /* 정확한 너비 설정 */
    height: 564.94px; /* 정확한 높이 설정 */
    margin: 0 auto;
    padding-bottom: 0; /* 패딩 제거하여 정확한 크기 보장 */
    background: #ffffff;
    border: 1px solid #000000;
    display: block;
}





#signalChart {
    background: #ffffff;
    border: 1px solid #000000;
    max-width: 100%;
    height: 100% !important;
}

/* Guide Section */
.guide-section {
    background: #ffffff;
    padding: 30px;
    border: 1px solid #000000;
    margin-bottom: 30px;
    border-radius: 0;
}

.guide-section h2 {
    color: #000000;
    margin-bottom: 25px;
    text-align: center;
    font-size: 1.8rem;
}

.guide-content h3 {
    color: #000000;
    margin: 20px 0 10px 0;
    font-size: 1.3rem;
}

.guide-content p {
    margin-bottom: 15px;
    color: #000000;
    line-height: 1.7;
}

.guide-content ul {
    margin: 15px 0;
    padding-left: 25px;
}

.guide-content li {
    margin-bottom: 8px;
    color: #000000;
}

/* Comparison Section */
.comparison-section {
    background: #ffffff;
    padding: 30px;
    border: 1px solid #000000;
    margin-bottom: 30px;
    border-radius: 0;
}

.comparison-section h2 {
    color: #000000;
    margin-bottom: 25px;
    text-align: center;
    font-size: 1.8rem;
}

.comparison-table {
    overflow-x: auto;
}

.comparison-table table {
    width: 100%;
    border-collapse: collapse;
    background: #ffffff;
    border: 1px solid #000000;
}

.comparison-table th,
.comparison-table td {
    padding: 15px;
    text-align: center;
    border: 1px solid #000000;
}

.comparison-table th {
    background: #000000;
    color: #ffffff;
    font-weight: 600;
}

.comparison-table tr:nth-child(even) {
    background: #ffffff;
}

.comparison-table tr:hover {
    background: #f0f0f0;
}

/* Router Specifications Section */
.router-specs {
    background: #ffffff;
    border: 1px solid #000000;
    margin: 30px 0;
    padding: 20px;
}

.router-specs h2 {
    color: #000000;
    text-align: center;
    margin-bottom: 20px;
    border-bottom: 1px solid #000000;
    padding-bottom: 10px;
    font-size: 1.3rem;
}

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

.spec-group {
    border: 1px solid #000000;
    padding: 15px;
    background: #ffffff;
}

.spec-group h3 {
    color: #000000;
    margin-bottom: 15px;
    text-align: center;
    border-bottom: 1px solid #000000;
    padding-bottom: 8px;
    font-size: 1rem;
}

.spec-item {
    margin-bottom: 15px;
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.spec-item label {
    color: #000000;
    font-weight: 600;
    font-size: 0.8rem;
}

.spec-item input[type="range"] {
    width: 100%;
    height: 4px;
    background: #f0f0f0;
    border: 1px solid #000000;
    border-radius: 0;
    outline: none;
    cursor: pointer;
}

.spec-item input[type="range"]::-webkit-slider-thumb {
    appearance: none;
    width: 16px;
    height: 16px;
    background: #000000;
    border: 1px solid #000000;
    border-radius: 0;
    cursor: pointer;
}

.spec-item input[type="range"]::-moz-range-thumb {
    width: 16px;
    height: 16px;
    background: #000000;
    border: 1px solid #000000;
    border-radius: 0;
    cursor: pointer;
}

.spec-item select {
    padding: 6px 10px;
    border: 1px solid #000000;
    background: #ffffff;
    color: #000000;
    border-radius: 0;
    font-size: 0.8rem;
    cursor: pointer;
}

.spec-item select:focus {
    outline: none;
    border-color: #000000;
}

.value-display {
    color: #000000;
    font-weight: 600;
    font-size: 0.8rem;
    text-align: center;
    padding: 4px 8px;
    background: #f8f9fa;
    border: 1px solid #000000;
    border-radius: 0;
}

/* Specifications Summary */
.specs-summary {
    border: 1px solid #000000;
    padding: 15px;
    background: #ffffff;
}

.specs-summary h3 {
    color: #000000;
    text-align: center;
    margin-bottom: 15px;
    border-bottom: 1px solid #000000;
    padding-bottom: 8px;
    font-size: 1rem;
}

.summary-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 10px;
}

.summary-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px 12px;
    background: #f8f9fa;
    border: 1px solid #000000;
    border-radius: 0;
}

.summary-item .label {
    color: #000000;
    font-weight: 600;
    font-size: 0.8rem;
}

.summary-item .value {
    color: #000000;
    font-size: 0.8rem;
    text-align: right;
}

/* Broadband Specifications Section */
.broadband-specs {
    background: #ffffff;
    border: 1px solid #000000;
    margin: 30px 0;
    padding: 20px;
}

.broadband-specs h2 {
    color: #000000;
    text-align: center;
    margin-bottom: 20px;
    border-bottom: 1px solid #000000;
    padding-bottom: 10px;
    font-size: 1.3rem;
}

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

.broadband-group {
    border: 1px solid #000000;
    padding: 15px;
    background: #ffffff;
}

.broadband-group h3 {
    color: #000000;
    margin-bottom: 15px;
    text-align: center;
    border-bottom: 1px solid #000000;
    padding-bottom: 8px;
    font-size: 1rem;
}

.broadband-item {
    margin-bottom: 15px;
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.broadband-item label {
    color: #000000;
    font-weight: 600;
    font-size: 0.8rem;
}

.speed-input-group {
    display: flex;
    gap: 8px;
    align-items: center;
}

.speed-input-group input[type="number"] {
    flex: 1;
    padding: 6px 10px;
    border: 1px solid #000000;
    background: #ffffff;
    color: #000000;
    border-radius: 0;
    font-size: 0.8rem;
    min-width: 80px;
}

.speed-input-group select {
    padding: 6px 10px;
    border: 1px solid #000000;
    background: #ffffff;
    color: #000000;
    border-radius: 0;
    font-size: 0.8rem;
    min-width: 70px;
}

.broadband-item select {
    padding: 6px 10px;
    border: 1px solid #000000;
    background: #ffffff;
    color: #000000;
    border-radius: 0;
    font-size: 0.8rem;
    cursor: pointer;
}

.broadband-item select:focus,
.speed-input-group input:focus,
.speed-input-group select:focus {
    outline: none;
    border-color: #007AFF;
}

/* Broadband Summary */
.broadband-summary {
    border: 1px solid #000000;
    padding: 15px;
    background: #ffffff;
}

.broadband-summary h3 {
    color: #000000;
    text-align: center;
    margin-bottom: 15px;
    border-bottom: 1px solid #000000;
    padding-bottom: 8px;
    font-size: 1rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 15px;
    }
    
    header h1 {
        font-size: 2rem;
    }
    
    .control-panel {
        grid-template-columns: 1fr;
    }
    
    .results-grid {
        grid-template-columns: 1fr;
    }
    
    .knowledge-grid {
        grid-template-columns: 1fr;
    }
    
    .action-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .btn-primary, .btn-secondary, .btn-success {
        width: 100%;
        max-width: 300px;
        min-height: 44px; /* 터치하기 쉬운 최소 높이 */
        font-size: 16px; /* 모바일에서 읽기 쉬운 폰트 크기 */
    }
    
    .nav-btn {
        min-height: 44px; /* 터치하기 쉬운 최소 높이 */
        font-size: 14px;
    }
    
    .settings-button {
        min-height: 44px;
        font-size: 20px;
    }
    
    #signalChart {
        width: 100%;
        height: 300px;
        z-index: 1000;
    }

    .specs-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    .summary-grid {
        grid-template-columns: 1fr;
    }
    
    .spec-item {
        margin-bottom: 15px;
    }
    
    .router-specs {
        padding: 20px;
        margin: 20px 0;
    }

    .broadband-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    .broadband-item {
        margin-bottom: 15px;
    }
    
    .broadband-specs {
        padding: 20px;
        margin: 20px 0;
    }
    
    .speed-input-group {
        flex-direction: column;
        align-items: stretch;
    }
    
    .speed-input-group input[type="number"],
    .speed-input-group select {
        min-width: auto;
    }
    
    .settings-button-container {
        top: 90px;
        right: 20px;
        width: 55px;
        height: 55px;
    }
    
    .settings-modal {
        margin: 20px;
        max-height: calc(100vh - 40px);
    }
    
    .settings-modal-body {
        padding: 25px;
    }
    
    .real-time-graph {
        padding: 25px;
    }
    
    .real-time-graph h3 {
        font-size: 1.4rem;
        margin-bottom: 20px;
    }
}

@media (max-width: 480px) {
    header {
        padding: 15px;
    }
    
    .nav-header-fixed {
        height: 50px;
        padding: 0 15px;
    }
    
    .nav-controls {
        gap: 8px;
    }
    
    .nav-btn {
        padding: 8px 12px;
        font-size: 12px;
        min-width: 80px;
    }
    
    .main-content {
        margin-top: 50px;
    }
    
    .knowledge-section,
    .experiment-section,
    .results-section,
    .guide-section,
    .comparison-section {
        padding: 15px;
        margin-bottom: 20px;
    }
    
    .control-group {
        margin-bottom: 15px;
    }
    
    .settings-button-container {
        top: 70px;
        right: 15px;
        width: 50px;
        height: 50px;
    }
    
    .settings-button {
        font-size: 18px;
    }
    
    .settings-modal {
        margin: 10px;
        max-height: calc(100vh - 20px);
        width: calc(100vw - 20px);
        max-width: none;
    }
    
    .settings-modal-body {
        padding: 15px;
        max-height: calc(100vh - 60px);
        overflow-y: auto;
    }
    
    .settings-modal h2 {
        font-size: 1.3rem;
        margin-bottom: 15px;
    }
    
    .settings-modal h3 {
        font-size: 1.1rem;
        margin-bottom: 10px;
    }
    
    .specs-grid {
        grid-template-columns: 1fr;
        gap: 15px;
    }
    
    .broadband-grid {
        grid-template-columns: 1fr;
        gap: 15px;
    }
    
    #signalChart {
        width: 100%;
        height: 200px;
    }
    
    .real-time-graph {
        padding: 15px;
    }
    
    .real-time-graph h3 {
        font-size: 1.2rem;
        margin-bottom: 15px;
    }
}

@media (max-width: 320px) {
    .nav-header-fixed {
        height: 45px;
        padding: 0 10px;
    }
    
    .nav-controls {
        gap: 6px;
    }
    
    .nav-btn {
        padding: 6px 10px;
        font-size: 11px;
        min-width: 70px;
    }
    
    .main-content {
        margin-top: 45px;
    }
    
    .knowledge-section,
    .experiment-section,
    .results-section,
    .guide-section,
    .comparison-section {
        padding: 10px;
        margin-bottom: 15px;
    }
    
    .settings-button-container {
        top: 60px;
        right: 10px;
        width: 45px;
        height: 45px;
    }
    
    .settings-button {
        font-size: 16px;
    }
    
    .settings-modal {
        margin: 5px;
        max-height: calc(100vh - 10px);
    }
    
    .settings-modal-body {
        padding: 10px;
    }
    
    .specs-grid,
    .broadband-grid {
        gap: 10px;
    }
    
    #signalChart {
        height: 150px;
    }
    
    .real-time-graph {
        padding: 10px;
    }
    
    .real-time-graph h3 {
        font-size: 1.1rem;
        margin-bottom: 10px;
    }
    
    .control-group label {
        font-size: 14px;
    }
    
    .control-group input,
    .control-group select {
        font-size: 14px;
        padding: 8px;
    }
}

/* Animation Classes */
.fade-in {
    animation: fadeIn 0.5s ease-in;
}

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

.slide-in {
    animation: slideIn 0.5s ease-out;
}

@keyframes slideIn {
    from {
        transform: translateX(-100%);
    }
    to {
        transform: translateX(0);
    }
}

/* Loading Animation */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 1px solid #000000;
    border-top: 1px solid #000000;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

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

/* Success/Error States - Only for non-notification elements */
.success:not(.notification) {

    background-color: #000000 !important;
}

.error:not(.notification) {

    background-color: #000000 !important;
}

.warning:not(.notification) {

    background-color: #000000 !important;
}

/* Notification Styles */
.notification {
    position: fixed !important;
    top: 20px !important;
    right: 20px !important;
    padding: 15px 20px !important;
    border-radius: 0 !important;
    color: #ffffff !important;
    font-weight: 600 !important;
    z-index: 1000 !important;
    border: 1px solid #000000 !important;
    background-color: #000000 !important;
}

.notification.success,
.notification.warning,
.notification.error,
.notification.info {
    background-color: #000000 !important;
    color: #ffffff !important;
    border: 1px solid #000000 !important;
}

/* Footer Styles */
.footer {
    background: #ffffff;
    border-top: 1px solid #000000;
    margin-top: 50px;
    padding: 40px 0 20px 0;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 40px;
}

.footer-section h3 {
    color: #000000;
    margin-bottom: 15px;
    font-size: 1.2rem;
    border-bottom: 1px solid #000000;
    padding-bottom: 10px;
}

.footer-section p {
    color: #000000;
    line-height: 1.6;
    margin-bottom: 15px;
}

/* Git Shortcuts */
.git-shortcuts {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.git-btn {
    display: inline-block;
    padding: 10px 15px;
    background: #ffffff;
    color: #000000;
    text-decoration: none;
    border: 1px solid #000000;
    border-radius: 0;
    transition: all 0.3s ease;
    text-align: center;
    font-weight: 500;
}

.git-btn:hover {
    background: #000000;
    color: #ffffff;
    transform: translateY(-2px);
}

.git-btn span {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

/* Contact Info */
.contact-info {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.contact-btn {
    display: inline-block;
    padding: 10px 15px;
    background: #ffffff;
    color: #000000;
    text-decoration: none;
    border: 1px solid #000000;
    border-radius: 0;
    transition: all 0.3s ease;
    text-align: center;
    font-weight: 500;
}

.contact-btn:hover {
    background: #000000;
    color: #ffffff;
    transform: translateY(-2px);
}

.contact-btn span {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

.email-btn:hover {
    background: #007AFF;
    color: #ffffff;
    border-color: #007AFF;
}

.github-btn:hover {
    background: #333333;
    color: #ffffff;
    border-color: #333333;
}

/* Footer Bottom */
.footer-bottom {
    text-align: center;
    margin-top: 30px;
    padding-top: 20px;
    border-top: 1px solid #000000;
}

.footer-bottom p {
    color: #000000;
    font-size: 0.9rem;
}

/* Responsive Footer */
@media (max-width: 768px) {
    .footer-content {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .git-shortcuts {
        flex-direction: row;
        flex-wrap: wrap;
        justify-content: center;
    }
    
    .git-btn {
        min-width: 120px;
    }
}

/* Dynamic Messages */
.dynamic-message {
    display: flex;
    align-items: flex-start;
    gap: 8px;
    margin-top: 8px;
    padding: 8px 10px;
    background: #f8f9fa;
    border: 1px solid #000000;
    border-radius: 0;
    font-size: 0.75rem;
    line-height: 1.4;
    transition: all 0.3s ease;
}

.message-icon {
    color: #007AFF;
    font-size: 0.9rem;
    flex-shrink: 0;
    margin-top: 1px;
}

.message-text {
    color: #000000;
    font-weight: 500;
}

/* Hover effect for messages */
.dynamic-message:hover {
    background: #e9ecef;
    border-color: #007AFF;
}

.dynamic-message:hover .message-icon {
    color: #0056b3;
}

/* Responsive messages */
@media (max-width: 768px) {
    .dynamic-message {
        font-size: 0.7rem;
        padding: 6px 8px;
    }
    
    .message-icon {
        font-size: 0.8rem;
    }
}

/* JSON Import Section */
.json-import-section {
    border: 1px solid #000000;
    padding: 20px;
    margin: 20px 0;
    background: #ffffff;
}

.json-import-section h3 {
    color: #000000;
    margin-bottom: 15px;
    text-align: center;
    border-bottom: 1px solid #000000;
    padding-bottom: 10px;
    font-size: 1.1rem;
}

.file-upload-area {
    display: flex;
    align-items: center;
    gap: 15px;
    margin-bottom: 20px;
    padding: 15px;
    background: #f8f9fa;
    border: 1px solid #000000;
    border-radius: 0;
}

.file-name {
    color: #000000;
    font-size: 0.9rem;
    font-style: italic;
    flex: 1;
}

.import-options {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 10px;
    margin-bottom: 20px;
}

.import-options label {
    display: flex;
    align-items: center;
    gap: 8px;
    color: #000000;
    font-size: 0.9rem;
    cursor: pointer;
    padding: 8px 12px;
    background: #f8f9fa;
    border: 1px solid #000000;
    border-radius: 0;
}

.import-options input[type="checkbox"] {
    width: 16px;
    height: 16px;
    accent-color: #000000;
}

.import-status {
    margin-top: 15px;
    padding: 10px;
    border: 1px solid #000000;
    border-radius: 0;
    font-size: 0.9rem;
    min-height: 20px;
}

.import-status.success {
    background: #d4edda;
    color: #155724;
    border-color: #155724;
}

.import-status.error {
    background: #f8d7da;
    color: #721c24;
    border-color: #721c24;
}

.import-status.info {
    background: #d1ecf1;
    color: #0c5460;
    border-color: #0c5460;
}

/* Responsive Design */
@media (max-width: 768px) {
    .file-upload-area {
        flex-direction: column;
        align-items: stretch;
        gap: 10px;
    }
    
    .import-options {
        grid-template-columns: 1fr;
    }
    
    .json-import-section {
        padding: 15px;
        margin: 15px 0;
    }
}

/* Settings Button */
.settings-button-container {
    position: fixed;
    top: 100px; /* 20px에서 100px로 변경하여 네비게이션 아래에 배치 */
    right: 20px;
    z-index: 1000;
    cursor: grab; /* 드래그 가능함을 나타내는 커서 */
    user-select: none; /* 텍스트 선택 방지 */
    width: 60px; /* 명시적 너비 설정 */
    height: 60px; /* 명시적 높이 설정 */
    display: flex;
    align-items: center;
    justify-content: center;
    /* 드래그 성능 향상을 위한 CSS 최적화 */
    will-change: transform, left, top;
    transition: none; /* 드래그 중에는 transition 제거하여 부드러운 이동 */
}

.settings-button-container:active {
    cursor: grabbing; /* 드래그 중일 때 커서 변경 */
}

.settings-button-container:hover {
    cursor: grab; /* 호버 시 드래그 가능함을 표시 */
}

/* 드래그 중일 때 transition 제거 */
.settings-button-container.dragging {
    transition: none !important;
}

.settings-button {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.1); /* 투명 배경 */
    border: none; /* 테두리 제거 */
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
    backdrop-filter: blur(15px); /* 기본 백블러 */
    -webkit-backdrop-filter: blur(15px);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    position: relative; /* 상대 위치 설정 */
    z-index: 1; /* 버튼이 컨테이너 위에 오도록 */
    /* 드래그 중에도 버튼 자체는 transition 유지 */
}

.settings-button:hover {
    background: rgba(255, 255, 255, 0.2); /* 호버 시 배경 투명도 증가 */
    backdrop-filter: blur(25px); /* 호버 시 블러 증가 */
    -webkit-backdrop-filter: blur(25px);
    transform: scale(1.05);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
}

.settings-button:active {
    backdrop-filter: blur(1px); /* 드래그 시 블러 최소화 */
    -webkit-backdrop-filter: blur(1px);
    transform: scale(0.95);
}

.settings-icon {
    font-size: 1.5rem;
    pointer-events: none; /* 아이콘이 클릭 이벤트를 방해하지 않도록 */
}

/* 드래그 힌트 스타일 */
.drag-hint {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

/* 실험 상태 표시 스타일 */
.experiment-status {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

/* Settings Modal */
.settings-modal {
    display: none;
    position: fixed;
    z-index: 2000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    overflow-y: auto;
    scrollbar-color: rgba(0, 0, 0, 0) transparent;
}

.settings-modal.show {
    display: block;
}

.settings-modal-content {
    background-color: #ffffff;
    margin: 20px auto;
    padding: 0;
    border: 2px solid #000000;
    width: 95%;
    max-width: 1200px;
    max-height: 90vh;
    overflow-y: auto;
    position: relative;
}

.settings-modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px;
    border-bottom: 2px solid #000000;
    background: #f8f9fa;
    position: sticky;
    top: 0;
    z-index: 10;
}

.settings-modal-header h2 {
    margin: 0;
    color: #000000;
    font-size: 1.5rem;
}

.close-settings {
    background: none;
    border: none;
    font-size: 2rem;
    cursor: pointer;
    color: #000000;
    padding: 0;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
}

.close-settings:hover {
    background: #000000;
    color: #ffffff;
}

.settings-modal-body {
    padding: 20px;
}

/* Modal 내부의 설정 섹션 스타일 조정 */
.settings-modal .router-specs,
.settings-modal .broadband-specs {
    border: none;
    margin: 0 0 30px 0;
    padding: 0;
}

.settings-modal .router-specs h2,
.settings-modal .broadband-specs h2 {
    font-size: 1.3rem;
    margin-bottom: 20px;
    padding-bottom: 10px;
    border-bottom: 1px solid #000000;
}

/* Responsive Design */
@media (max-width: 768px) {
    .settings-button {
        width: 50px;
        height: 50px;
    }
    
    .settings-icon {
        font-size: 1.2rem;
    }
    
    .settings-modal-content {
        width: 98%;
        margin: 10px auto;
        max-height: 95vh;
    }
    
    .settings-modal-header {
        padding: 15px;
    }
    
    .settings-modal-header h2 {
        font-size: 1.3rem;
    }
    
    .settings-modal-body {
        padding: 15px;
    }
}

/* JSON Import Section */
.json-import-section {
    border: 1px solid #000000;
    padding: 20px;
    margin: 20px 0;
    background: #ffffff;
}

/* 설정 모달 내 JSON import 섹션 스타일 */
.settings-modal .json-import-section {
    border: 1px solid #000000;
    padding: 15px;
    margin: 15px 0;
    background: #ffffff;
    border-radius: 0;
}

.settings-modal .json-import-section h3 {
    color: #000000;
    margin-bottom: 15px;
    text-align: center;
    border-bottom: 1px solid #000000;
    padding-bottom: 8px;
    font-size: 1.1rem;
}

.settings-modal .file-upload-area {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 15px;
    padding: 10px;
    background: #f8f9fa;
    border: 1px solid #000000;
    border-radius: 0;
}

.settings-modal .import-options {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 8px;
    margin-bottom: 15px;
}

.settings-modal .import-options label {
    display: flex;
    align-items: center;
    gap: 6px;
    color: #000000;
    font-size: 0.85rem;
    cursor: pointer;
    padding: 6px 10px;
    background: #f8f9fa;
    border: 1px solid #000000;
    border-radius: 0;
}

.settings-modal .import-status {
    margin-top: 10px;
    padding: 8px;
    border: 1px solid #000000;
    border-radius: 0;
    font-size: 0.85rem;
    min-height: 18px;
}

/* Logo Styles */
.logo-container {
    display: flex;
    align-items: center;
    gap: 15px;
}

.logo-svg {
    width: 80px;
    height: 80px;
    flex-shrink: 0;
    transition: transform 0.3s ease;
}

.logo-svg:hover {
    transform: scale(1.1);
}

/* 기본 로고 (80x80) */
.logo-80 {
    width: 40px;
    height: 40px;
    display: block;
}

.logo-60 {
    width: 35px;
    height: 35px;
    display: none;
}

.logo-50 {
    width: 30px;
    height: 30px;
    display: none;
}

.logo-text h1 {
    margin: 0;
    font-size: 1.4rem;
    font-weight: bold;
    color: #000000;
    letter-spacing: -0.5px;
}

.logo-text p {
    display: none; /* 부제목 숨김 */
}

/* Responsive Logo */
@media (max-width: 768px) {
    .logo-container {
        flex-direction: column;
        text-align: center;
        gap: 10px;
    }
    
    .logo-80 {
        display: none;
    }
    
    .logo-60 {
        display: block;
    }
    
    .logo-text h1 {
        font-size: 1.6rem;
    }
    
    .logo-text p {
        font-size: 0.8rem;
    }
    
    .nav-header-fixed {
        height: 55px;
        padding: 0 15px;
    }
    
    .nav-controls {
        gap: 10px;
    }
    
    .nav-btn {
        padding: 6px 10px;
        font-size: 0.75rem;
        min-width: 85px;
    }
    
    .main-content {
        margin-top: 55px;
    }
    
    .settings-button-container {
        top: 80px;
        right: 20px;
        width: 55px;
        height: 55px;
    }
    
    .settings-modal {
        margin: 15px;
        max-height: calc(100vh - 30px);
    }
    
    .settings-modal-body {
        padding: 20px;
    }
    
    .specs-grid,
    .broadband-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 20px;
    }
    
    #signalChart {
        width: 100%;
        height: 400px;
    }
    
    .real-time-graph {
        padding: 20px;
    }
}

@media (max-width: 480px) {
    .logo-60 {
        display: none;
    }
    
    .logo-50 {
        display: block;
    }
    
    .logo-text h1 {
        font-size: 1.4rem;
    }
    
    .logo-text p {
        font-size: 0.75rem;
    }
}

/* Fixed Navigation Header */
.nav-header-fixed {
    position: fixed;
    height: 60px;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(3px);
    -webkit-backdrop-filter: blur(3px);
    border: none; /* 테두리 제거 */
    z-index: 1000;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.1);
    
    /* nav-container 스타일을 여기로 이동 */
    max-width: none; /* 최대 너비 제한 제거 */
    width: 100%; /* 전체 너비 사용 */
    margin: 0; /* 마진 제거 */
    padding: 4px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 10px;
}

/* nav-container 클래스 제거 - nav-header-fixed로 통합 */

.nav-controls {
    display: flex;
    align-items: center;
}

.nav-button-group {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

.nav-btn {
    display: flex;
    align-items: center;
    gap: 4px;
    padding: 4px 12px;
    border: 1px solid rgba(0, 0, 0, 0.2);
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(5px);
    -webkit-backdrop-filter: blur(5px);
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 0.8rem;
    font-weight: 600;
    text-decoration: none;
    color: #000000;
    border-radius: 4px;
    min-width: 90px;
    justify-content: center;
}

.nav-btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.15);
    background: rgba(255, 255, 255, 1);
}

.nav-btn-primary {
    background: rgba(0, 0, 0, 0.9);
    color: #ffffff;
    border-color: rgba(0, 0, 0, 0.3);
}

.nav-btn-primary:hover {
    background: rgba(0, 0, 0, 1);
}

.nav-btn-secondary {
    background: rgba(255, 255, 255, 0.9);
    color: #000000;
}

.nav-btn-secondary:hover {
    background: rgba(255, 255, 255, 1);
}

.nav-btn-success {
    background: rgba(40, 167, 69, 0.9);
    color: #ffffff;
    border-color: rgba(40, 167, 69, 0.3);
}

.nav-btn-success:hover {
    background: rgba(40, 167, 69, 1);
}

.btn-icon {
    font-size: 0.9rem;
}

.btn-text {
    white-space: nowrap;
}

/* Main Content with top margin for fixed header */
.main-content {
    margin-top: 60px; /* Adjusted to match new header height */
    padding: 20px;
}

/* Responsive Fixed Navigation */
@media (max-width: 1024px) {
    .nav-header-fixed {
        flex-direction: column;
        align-items: stretch;
        text-align: center;
        padding: 4px 15px;
    }
    
    .nav-controls {
        justify-content: center;
    }
    
    .nav-button-group {
        justify-content: center;
    }
    
    .main-content {
        margin-top: 50px;
    }
}

@media (max-width: 768px) {
    .nav-button-group {
        flex-direction: column;
        width: 100%;
    }
    
    .nav-btn {
        width: 100%;
        min-width: auto;
    }
    
    .logo-container {
        margin-bottom: 8px;
    }
    
    .main-content {
        margin-top: 60px;
        padding: 15px;
    }
}

@media (max-width: 480px) {
    .nav-header-fixed {
        padding: 3px 12px;
    }
    
    .nav-btn {
        padding: 3px 10px;
        font-size: 0.75rem;
    }
    
    .btn-icon {
        font-size: 0.8rem;
    }
    
    .main-content {
        margin-top: 50px;
        padding: 10px;
    }
}

/* Chart Section */
.real-time-graph {
    margin: 30px 0;
    padding: 25px;
    border: 1px solid #000000;
    background: #ffffff;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.real-time-graph h3 {
    margin: 0 0 25px 0;
    font-size: 1.4rem;
    color: #000000;
    text-align: center;
    font-weight: 600;
}

.chart-container {
    width: 100%;
    height: 450px;
    border: 1px solid #e0e0e0;
    background: #ffffff;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 4px;
}

#signalChart {
    max-width: 100%;
    max-height: 100%;
    display: block;
}



/* Responsive Results Grid */
@media (max-width: 1024px) {
    .results-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 20px;
    }
}

@media (max-width: 768px) {
    .results-grid {
        grid-template-columns: 1fr;
        gap: 15px;
    }
    
    .result-card {
        padding: 25px 20px;
    }
    
    .result-card h3 {
        font-size: 1.2rem;
        margin-bottom: 20px;
    }
}
