:root {
    --primary-bg: #ffffff;
    --secondary-bg: #f8f9fa;
    --tertiary-bg: #f1f3f4;
    --primary-text: #000000;
    --secondary-text: #666666;
    --accent-color: #333333;
    --border-color: #cccccc;
    --shadow-color: rgba(0, 0, 0, 0.1);
    --card-bg: #ffffff;
    --badge-true: #000000;
    --badge-false: #666666;
    --badge-mixed: #999999;
    --badge-unverified: #cccccc;
    --badge-text: #ffffff;
}

.dark-theme {
    --primary-bg: #000000;
    --secondary-bg: #1a1a1a;
    --tertiary-bg: #333333;
    --primary-text: #ffffff;
    --secondary-text: #cccccc;
    --accent-color: #ffffff;
    --border-color: #666666;
    --shadow-color: rgba(0, 0, 0, 0.5);
    --card-bg: #1a1a1a;
    --badge-true: #ffffff;
    --badge-false: #cccccc;
    --badge-mixed: #999999;
    --badge-unverified: #666666;
    --badge-text: #000000;
}

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

/* Skip link for accessibility */
.skip-link {
    position: absolute;
    top: -40px;
    left: 6px;
    background: var(--accent-color);
    color: var(--primary-bg);
    padding: 8px;
    text-decoration: none;
    border-radius: 4px;
    z-index: 1000;
    transition: top 0.3s ease;
}

.skip-link:focus {
    top: 6px;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background-color: var(--primary-bg);
    color: var(--primary-text);
    line-height: 1.6;
    transition: background-color 0.3s ease, color 0.3s ease;
}

.container {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Header */
header {
    background-color: var(--primary-bg);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    max-width: 800px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.75rem;
    font-weight: 600;
    color: var(--primary-text);
    letter-spacing: -0.5px;
}

.theme-toggle {
    background: none;
    border: 1px solid var(--border-color);
    border-radius: 50%;
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
    background-color: var(--secondary-bg);
    will-change: transform, background-color;
}

.theme-toggle:hover,
.theme-toggle:focus-visible {
    background-color: var(--tertiary-bg);
    border-color: var(--accent-color);
}

.theme-toggle:focus-visible {
    outline: 2px solid var(--accent-color);
    outline-offset: 2px;
}

.theme-toggle svg {
    color: var(--primary-text);
    transition: opacity 0.3s ease;
}

.light-theme .moon-icon,
.dark-theme .sun-icon {
    opacity: 0;
    position: absolute;
}

.light-theme .sun-icon,
.dark-theme .moon-icon {
    opacity: 1;
}

/* Main Content */
main {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 2rem;
    text-align: center;
}

.search-container {
    max-width: 600px;
    width: 100%;
    margin-bottom: 3rem;
}

.search-box {
    position: relative;
    margin-bottom: 1.5rem;
}

#searchInput {
    width: 100%;
    padding: 1rem 3.5rem 1rem 1.5rem;
    font-size: 1.1rem;
    border: 1px solid var(--border-color);
    border-radius: 24px;
    background-color: var(--primary-bg);
    color: var(--primary-text);
    transition: all 0.3s ease;
    box-shadow: 0 2px 8px var(--shadow-color);
}

#searchInput:focus {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 4px 16px var(--shadow-color);
}

#searchInput:invalid {
    border-color: var(--badge-false);
}

#searchInput:valid {
    border-color: var(--badge-true);
}

#searchInput::placeholder {
    color: var(--secondary-text);
}

.search-button {
    position: absolute;
    right: 8px;
    top: 50%;
    transform: translateY(-50%);
    background-color: var(--accent-color);
    border: none;
    border-radius: 50%;
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
}

.search-button:hover,
.search-button:focus-visible {
    background-color: var(--primary-text);
    transform: translateY(-50%) scale(1.05);
}

.search-button:focus-visible {
    outline: 2px solid var(--accent-color);
    outline-offset: 2px;
}

.search-button svg {
    color: var(--primary-bg);
}

.search-subtitle {
    color: var(--secondary-text);
    font-size: 0.95rem;
    font-weight: 400;
}

/* Results */
.results-container {
    max-width: 800px;
    width: 100%;
    margin-top: 2rem;
}

.result-card {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 2rem;
    box-shadow: 0 4px 16px var(--shadow-color);
    text-align: left;
}

.result-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--border-color);
}

.result-header h2 {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--primary-text);
}

.verification-badge {
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 500;
    background-color: var(--badge-unverified);
    color: var(--badge-text);
}

.verification-badge.true {
    background-color: var(--badge-true);
}

.verification-badge.false {
    background-color: var(--badge-false);
}

.verification-badge.mixed {
    background-color: var(--badge-mixed);
}

.result-content > div {
    margin-bottom: 2rem;
}

.result-content h3 {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--primary-text);
    margin-bottom: 0.75rem;
}

/* Confidence Section Styling */
.confidence-section {
    background-color: var(--tertiary-bg);
    border-radius: 8px;
    padding: 1.5rem;
    margin: 1.5rem 0;
    border: 1px solid var(--border-color);
}

.confidence-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1rem;
    margin-top: 1rem;
}

.confidence-item {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.confidence-item strong {
    color: var(--primary-text);
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.confidence-value {
    color: var(--primary-text);
    font-weight: 600;
    font-size: 1rem;
}

.methodology-text,
.fact-checkers-text,
.last-updated {
    color: var(--secondary-text);
    font-size: 0.95rem;
    line-height: 1.5;
}

/* Responsive confidence grid */
@media (min-width: 768px) {
    .confidence-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (min-width: 1024px) {
    .confidence-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

.result-content p {
    color: var(--secondary-text);
    line-height: 1.7;
}

.result-content ul {
    list-style: none;
    padding: 0;
}

.result-content li {
    padding: 0.5rem 0;
    border-bottom: 1px solid var(--border-color);
    color: var(--secondary-text);
}

.result-content li:last-child {
    border-bottom: none;
}

/* Loading */
.loading-container {
    text-align: center;
    margin-top: 2rem;
}

.loading-spinner {
    width: 40px;
    height: 40px;
    border: 3px solid var(--border-color);
    border-top: 3px solid var(--accent-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 1rem;
    will-change: transform;
}

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

.loading-container p {
    color: var(--secondary-text);
    font-size: 0.95rem;
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 0.6; }
    50% { opacity: 1; }
}

/* Footer */
footer {
    text-align: center;
    padding: 2rem;
    color: var(--secondary-text);
    font-size: 0.875rem;
    border-top: 1px solid var(--border-color);
    background-color: var(--secondary-bg);
}

/* Sample hints styling */
.sample-hints p {
    color: var(--secondary-text);
    font-size: 0.85rem;
    margin-top: 1rem;
    opacity: 0.8;
    transition: opacity 0.3s ease;
}

.sample-hints p:hover {
    opacity: 1;
}

/* Search suggestions styling */
.search-suggestions {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    margin-top: 0.5rem;
    box-shadow: 0 4px 16px var(--shadow-color);
    max-height: 300px;
    overflow-y: auto;
    z-index: 1000;
}

.suggestion-item {
    padding: 0.75rem 1rem;
    cursor: pointer;
    border-bottom: 1px solid var(--border-color);
    transition: all 0.2s ease;
    color: var(--primary-text);
}

.suggestion-item:hover,
.suggestion-item.selected {
    background-color: var(--tertiary-bg);
    color: var(--accent-color);
}

.suggestion-item:last-child {
    border-bottom: none;
}

/* Search history styling */
.search-history {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    margin-top: 1rem;
    padding: 1rem;
    box-shadow: 0 4px 16px var(--shadow-color);
}

.search-history h4 {
    color: var(--primary-text);
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.history-item {
    padding: 0.5rem 0;
    cursor: pointer;
    color: var(--secondary-text);
    border-bottom: 1px solid var(--border-color);
    transition: color 0.2s ease;
}

.history-item:hover {
    color: var(--accent-color);
}

.history-item:last-child {
    border-bottom: none;
}

/* Error button styling */
.error-button {
    background: var(--accent-color);
    color: var(--primary-bg);
    border: none;
    padding: 0.5rem 1rem;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.9rem;
    transition: all 0.3s ease;
}

.error-button:hover {
    background: var(--primary-text);
    transform: translateY(-1px);
}

/* Responsive Design */
@media (max-width: 768px) {
    .header-content {
        padding: 0 1rem;
    }
    
    main {
        padding: 1rem;
    }
    
    .search-container {
        margin-bottom: 2rem;
    }
    
    #searchInput {
        font-size: 1rem;
        padding: 0.875rem 3rem 0.875rem 1.25rem;
    }
    
    .result-card {
        padding: 1.5rem;
    }
    
    .result-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }
    
    .verification-badge {
        align-self: flex-start;
    }
}

@media (max-width: 480px) {
    .logo {
        font-size: 1.5rem;
    }
    
    .search-container {
        margin-bottom: 1.5rem;
    }
    
    .result-card {
        padding: 1rem;
    }
}