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

:root {
    --primary-color: #3B82F6;
    --secondary-color: #1E40AF;
    --accent-color: #F97316;
    --success-color: #10B981;
    --warning-color: #F59E0B;
    --error-color: #EF4444;
    --background-color: #F8FAFC;
    --surface-color: #FFFFFF;
    --text-primary: #1F2937;
    --text-secondary: #6B7280;
    --border-color: #E5E7EB;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --border-radius: 12px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--background-color);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Header */
.header {
    background: var(--surface-color);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(10px);
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo h1 {
    display: none;
}

.logo-image {
    height: 40px;
    width: auto;
    margin-bottom: 4px;
}

.logo h1 {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: -4px;
}

.tagline {
    font-size: 0.875rem;
    color: var(--text-secondary);
    font-weight: 400;
}

.nav {
    display: flex;
    gap: 2rem;
}

.nav-link {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: 8px;
    transition: var(--transition);
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary-color);
    background-color: rgba(59, 130, 246, 0.05);
}

/* Main Content */
.main {
    padding: 4rem 0;
}

/* Hero Section */
.hero {
    text-align: center;
    margin-bottom: 4rem;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    line-height: 1.1;
}

.hero-description {
    font-size: 1.25rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
    line-height: 1.6;
}

/* Analyzer Section */
.analyzer {
    margin-bottom: 6rem;
}

.analyzer-card {
    background: var(--surface-color);
    border-radius: var(--border-radius);
    padding: 2.5rem;
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--border-color);
}

.analyzer-header {
    text-align: center;
    margin-bottom: 2rem;
}

.analyzer-header h3 {
    font-size: 1.75rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.analyzer-header p {
    color: var(--text-secondary);
    font-size: 1rem;
}

.input-section {
    max-width: 700px;
    margin: 0 auto;
}

.input-label {
    display: block;
    font-weight: 500;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.review-input {
    width: 100%;
    padding: 1rem;
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: 1rem;
    line-height: 1.5;
    font-family: inherit;
    resize: vertical;
    min-height: 150px;
    transition: var(--transition);
    background: var(--surface-color);
}

.review-input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.rating-input {
    margin: 1.5rem 0;
}

.rating-stars {
    display: flex;
    gap: 0.25rem;
    margin-top: 0.5rem;
}

.star {
    font-size: 1.5rem;
    color: #D1D5DB;
    cursor: pointer;
    transition: var(--transition);
}

.star:hover,
.star.active {
    color: var(--warning-color);
    transform: scale(1.1);
}

.analyze-btn {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    border: none;
    padding: 1rem 2rem;
    border-radius: var(--border-radius);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    width: 100%;
    position: relative;
    overflow: hidden;
    margin-top: 1rem;
}

.analyze-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

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

.analyze-btn.loading {
    pointer-events: none;
}

.loading-spinner {
    width: 20px;
    height: 20px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 1s linear infinite;
    position: absolute;
    right: 1rem;
    top: 50%;
    transform: translateY(-50%);
    display: none;
}

.analyze-btn.loading .loading-spinner {
    display: block;
}

.analyze-btn.loading .btn-text {
    opacity: 0.7;
}

@keyframes spin {
    to {
        transform: translateY(-50%) rotate(360deg);
    }
}

/* Results Section */
.results {
    margin-top: 2rem;
    transition: var(--transition);
}

.results.hidden {
    display: none;
}

.results-card {
    background: var(--surface-color);
    border-radius: var(--border-radius);
    padding: 2rem;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
}

.authenticity-score {
    display: flex;
    align-items: center;
    gap: 2rem;
    margin-bottom: 2rem;
    padding-bottom: 2rem;
    border-bottom: 1px solid var(--border-color);
}

.score-circle {
    position: relative;
    width: 120px;
    height: 120px;
    border-radius: 50%;
    background: conic-gradient(from 0deg, var(--primary-color) 0deg, var(--border-color) 0deg);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.score-circle::before {
    content: '';
    position: absolute;
    width: 90px;
    height: 90px;
    background: var(--surface-color);
    border-radius: 50%;
}

.score-value {
    font-size: 2rem;
    font-weight: 700;
    color: var(--text-primary);
    position: relative;
    z-index: 1;
}

.score-label {
    font-size: 0.75rem;
    color: var(--text-secondary);
    font-weight: 500;
    position: relative;
    z-index: 1;
    text-align: center;
}

.score-interpretation {
    flex: 1;
}

.score-status {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.score-description {
    color: var(--text-secondary);
    line-height: 1.5;
}

.analysis-details,
.recommendations {
    margin-bottom: 2rem;
}

.analysis-details h4,
.recommendations h4 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.detection-flags {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.flag-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem;
    background: var(--background-color);
    border-radius: 8px;
    border-left: 4px solid;
}

.flag-item.warning {
    border-left-color: var(--warning-color);
    background: rgba(245, 158, 11, 0.05);
}

.flag-item.error {
    border-left-color: var(--error-color);
    background: rgba(239, 68, 68, 0.05);
}

.flag-item.success {
    border-left-color: var(--success-color);
    background: rgba(16, 185, 129, 0.05);
}

.flag-icon {
    font-size: 1.25rem;
}

.flag-content h5 {
    font-weight: 600;
    font-size: 0.875rem;
    margin-bottom: 0.25rem;
}

.flag-content p {
    font-size: 0.875rem;
    color: var(--text-secondary);
    line-height: 1.4;
}

.recommendation-text {
    color: var(--text-secondary);
    line-height: 1.6;
    padding: 1rem;
    background: var(--background-color);
    border-radius: 8px;
    border-left: 4px solid var(--primary-color);
}

/* Features Section */
.features {
    margin-bottom: 6rem;
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 3rem;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.feature-card {
    background: var(--surface-color);
    padding: 2rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
    text-align: center;
    transition: var(--transition);
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
    display: block;
}

.feature-card h4 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.feature-card p {
    color: var(--text-secondary);
    line-height: 1.6;
}

/* About Section */
.about {
    margin-bottom: 4rem;
}

.about-content {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.about-content p {
    font-size: 1.125rem;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 1.5rem;
}

/* Footer */
.footer {
    background: var(--surface-color);
    border-top: 1px solid var(--border-color);
    padding: 3rem 0 1rem;
    margin-top: 4rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h4,
.footer-section h5 {
    font-weight: 600;
    margin-bottom: 1rem;
}

.footer-section h4 {
    color: var(--primary-color);
}

.footer-section ul {
    list-style: none;
}

.footer-section li {
    margin-bottom: 0.5rem;
}

.footer-section a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: var(--transition);
}

.footer-section a:hover {
    color: var(--primary-color);
}

.social-links {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.social-link {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-secondary);
    text-decoration: none;
    padding: 0.5rem;
    border-radius: 8px;
    transition: var(--transition);
    font-weight: 500;
}

.social-link:hover {
    color: var(--primary-color);
    background-color: rgba(59, 130, 246, 0.05);
    transform: translateX(4px);
}

.social-link svg {
    flex-shrink: 0;
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid var(--border-color);
    color: var(--text-secondary);
    font-size: 0.875rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 0 16px;
    }
    
    .header .container {
        flex-direction: column;
        gap: 1rem;
        text-align: center;
    }
    
    .nav {
        gap: 1rem;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-description {
        font-size: 1.125rem;
    }
    
    .analyzer-card {
        padding: 1.5rem;
    }
    
    .authenticity-score {
        flex-direction: column;
        text-align: center;
        gap: 1rem;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }
    
    .analyzer-card,
    .results-card {
        padding: 1rem;
    }
    
    .score-circle {
        width: 100px;
        height: 100px;
    }
    
    .score-circle::before {
        width: 75px;
        height: 75px;
    }
    
    .score-value {
        font-size: 1.5rem;
    }
}