/* ===== CSS Variables & Reset ===== */
:root {
    /* Colors */
    --primary-gradient: linear-gradient(135deg, #2563eb 0%, #0f766e 100%);
    --secondary-gradient: linear-gradient(135deg, #f97316 0%, #dc2626 100%);
    --accent-gradient: linear-gradient(135deg, #0f766e 0%, #2563eb 100%);

    --bg-dark: #f6f7f9;
    --bg-card: #ffffff;
    --bg-card-hover: #ffffff;

    --text-primary: #1f2937;
    --text-secondary: #4b5563;
    --text-muted: #8a94a3;

    --border-color: #d9dee7;
    --shadow-sm: 0 1px 2px rgba(31, 41, 55, 0.06);
    --shadow-md: 0 10px 30px rgba(31, 41, 55, 0.08);
    --shadow-lg: 0 18px 42px rgba(31, 41, 55, 0.12);

    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;

    /* Border Radius */
    --radius-sm: 8px;
    --radius-md: 10px;
    --radius-lg: 12px;
    --radius-xl: 999px;

    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
}

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

body {
    font-family: 'Inter', 'PingFang SC', 'Microsoft YaHei', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--bg-dark);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    overflow-x: hidden;
}

/* ===== Background Gradient ===== */
.bg-gradient {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    background:
        linear-gradient(180deg, rgba(255, 255, 255, 0.92) 0%, rgba(246, 247, 249, 0.92) 42%, #f6f7f9 100%),
        radial-gradient(circle at 8% 0%, rgba(37, 99, 235, 0.09) 0%, transparent 34%),
        radial-gradient(circle at 92% 6%, rgba(15, 118, 110, 0.08) 0%, transparent 30%);
}

@keyframes gradientShift {

    0%,
    100% {
        opacity: 1;
    }

    50% {
        opacity: 0.8;
    }
}

/* ===== Container ===== */
.container {
    max-width: 1120px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* ===== Header ===== */
.header {
    padding: 1.1rem 0;
    border-bottom: 1px solid var(--border-color);
    backdrop-filter: blur(16px);
    background: rgba(255, 255, 255, 0.88);
    position: sticky;
    top: 0;
    z-index: 100;
}

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

.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.logo h1 {
    font-size: 1.35rem;
    font-weight: 700;
    white-space: nowrap;
    line-height: 1.25;
}

.header-subtitle-container {
    margin-top: 0.15rem;
}

.header-subtitle {
    color: var(--text-secondary);
    font-size: 0.8125rem;
    margin-left: 44px;
    line-height: 1.35;
}

.header-actions {
    display: flex;
    gap: var(--spacing-sm);
}

.btn-icon {
    background: #ffffff;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    padding: var(--spacing-xs);
    cursor: pointer;
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
}

.btn-icon:hover {
    background: #eef5ff;
    color: #2563eb;
}

.btn-text {
    background: none;
    border: none;
    color: #2563eb;
    font-weight: 600;
    font-size: 0.875rem;
    cursor: pointer;
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-sm);
    transition: background var(--transition-fast);
}

.btn-text:hover {
    background: rgba(37, 99, 235, 0.08);
}

/* ===== Main Content ===== */
.main-content {
    padding: 2.25rem 0 3rem;
    min-height: calc(100vh - 200px);
}

/* ===== Layout Wrapper ===== */
.layout-wrapper {
    display: flex;
    gap: var(--spacing-xl);
    align-items: flex-start;
}

.search-content {
    flex: 1;
    min-width: 0;
}

.search-section {
    margin-bottom: var(--spacing-xl);
    max-width: 860px;
    margin-left: auto;
    margin-right: auto;
}

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

.search-card:hover {
    background: var(--bg-card-hover);
}

.search-title {
    font-size: 1.85rem;
    font-weight: 700;
    margin-bottom: var(--spacing-xs);
    color: var(--text-primary);
}

.search-subtitle {
    color: var(--text-secondary);
    margin-bottom: 1.25rem;
}

.seller-flow {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1rem;
    margin: 2rem 0 1.65rem;
    border-top: 1px solid #dce3ed;
}

.seller-flow-item {
    position: relative;
    min-width: 0;
    padding: 1.25rem 0.65rem 0;
    text-align: center;
}

.seller-flow-icon {
    position: absolute;
    top: -16px;
    left: 50%;
    transform: translateX(-50%);
    width: 32px;
    height: 32px;
    border-radius: 50%;
    background: #ffffff;
    border: 1px solid #0f766e;
    color: #0f766e;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.seller-flow-item strong {
    color: var(--text-primary);
    display: block;
    font-size: 0.9rem;
    line-height: 1.35;
}

.seller-flow-item small {
    display: block;
    margin-top: 0.25rem;
    color: var(--text-muted);
    font-size: 0.78rem;
    line-height: 1.35;
}

.search-form {
    display: grid;
    gap: var(--spacing-md);
}

.input-with-icon {
    position: relative;
    display: flex;
    align-items: center;
}

.input-with-icon input {
    width: 100%;
    padding-right: 60px !important;
}

.search-btn-absolute {
    position: absolute;
    right: 8px;
    top: 50%;
    transform: translateY(-50%);
    display: flex;
    align-items: center;
}

.search-btn-left {
    position: absolute;
    left: 8px;
    top: 50%;
    transform: translateY(-50%);
    display: flex;
    align-items: center;
}

.input-with-icon.left-icon input {
    padding-left: 60px !important;
    padding-right: 1rem !important;
}

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

.footer-link:hover {
    color: #2563eb;
    text-decoration: underline;
}

.btn-search-icon {
    background: var(--primary-gradient);
    border: none;
    border-radius: var(--radius-sm);
    color: white;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all var(--transition-fast);
    box-shadow: var(--shadow-sm);
}

.btn-search-icon:hover {
    box-shadow: 0 6px 14px rgba(37, 99, 235, 0.16);
}

.btn-paste {
    background: #eef2f7;
    color: #334155;
    border: 1px solid #d8dee8;
}

.btn-paste:hover {
    background: #e2e8f0;
    box-shadow: var(--shadow-sm);
}

.btn-search-large {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md);
    background: var(--primary-gradient);
    border: none;
    border-radius: var(--radius-sm);
    color: white;
    font-size: 1rem;
    font-weight: 650;
    cursor: pointer;
    transition: all var(--transition-normal);
    box-shadow: var(--shadow-md);
    margin-top: var(--spacing-sm);
}

.btn-search-large:hover {
    box-shadow: 0 12px 24px rgba(37, 99, 235, 0.18);
    filter: brightness(1.03);
}

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

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

.form-row {
    display: flex;
    gap: var(--spacing-md);
}

.flex-1 {
    flex: 1;
}

.image-upload-area {
    width: 100%;
    min-height: 150px;
    border: 1.5px dashed #c8d0dc;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all var(--transition-fast);
    position: relative;
    padding: var(--spacing-md);
}

.image-upload-area:hover,
.image-upload-area.drag-over {
    border-color: #2563eb;
    background: #f8fbff;
}

.upload-placeholder {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-sm);
    color: var(--text-muted);
    text-align: center;
}

.image-preview {
    position: relative;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
}

.image-preview img {
    max-height: 200px;
    border-radius: var(--radius-sm);
    box-shadow: var(--shadow-md);
}

.btn-remove-image {
    position: absolute;
    top: -10px;
    right: -10px;
    width: 24px;
    height: 24px;
    background: #ef4444;
    color: white;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    box-shadow: var(--shadow-sm);
}

/* ===== Thumbnail Selection ===== */
.thumbnail-selection-container {
    margin-top: var(--spacing-md);
    padding: var(--spacing-sm);
    background: #f8fafc;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
    animation: fadeIn 0.3s ease;
}

.thumbnail-label {
    font-size: 0.8125rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-sm);
    font-weight: 500;
}

.thumbnail-list {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}

.thumbnail-item {
    width: 64px;
    height: 64px;
    border-radius: var(--radius-sm);
    border: 2px solid transparent;
    overflow: hidden;
    cursor: pointer;
    transition: all var(--transition-fast);
    background: white;
    /* Ensure visibility for typical product images */
}

.thumbnail-item img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.thumbnail-item:hover {
    border-color: rgba(37, 99, 235, 0.5);
}

.thumbnail-item.selected {
    border-color: #2563eb;
    box-shadow: 0 0 0 2px rgba(37, 99, 235, 0.14);
}

.similarity-badge {
    position: absolute;
    top: 10px;
    right: 10px;
    padding: 4px 8px;
    background: var(--accent-gradient);
    border-radius: 4px;
    font-size: 0.75rem;
    font-weight: 700;
    color: white;
    box-shadow: var(--shadow-sm);
}

.similarity-badge.pending {
    background: var(--secondary-gradient);
    animation: pulsate 2s infinite;
}

.risk-badge {
    position: absolute;
    left: 10px;
    top: 10px;
    padding: 4px 8px;
    border-radius: 4px;
    font-size: 0.75rem;
    font-weight: 700;
    color: #ffffff;
    box-shadow: var(--shadow-sm);
}

.risk-badge.high {
    background: #dc2626;
}

.risk-badge.medium {
    background: #d97706;
}

.risk-badge.low {
    background: #0f766e;
}

@keyframes pulsate {
    0% { opacity: 1; }
    50% { opacity: 0.7; }
    100% { opacity: 1; }
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.form-group label {
    font-weight: 650;
    color: #374151;
    font-size: 0.875rem;
    text-transform: none;
    letter-spacing: 0;
}

.form-group input,
.form-group select {
    padding: var(--spacing-md);
    background: #ffffff;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    font-size: 1rem;
    font-family: inherit;
    transition: all var(--transition-fast);
}

.form-group select option {
    background-color: #ffffff;
    color: var(--text-primary);
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: #2563eb;
    background: #ffffff;
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.12);
}

.form-group input::placeholder {
    color: var(--text-muted);
}

.keyword-meaning-container {
    margin-top: var(--spacing-xs);
    padding: var(--spacing-xs) var(--spacing-sm);
    background: #eff6ff;
    border-radius: var(--radius-sm);
    display: flex;
    gap: var(--spacing-sm);
    align-items: center;
    border: 1px solid rgba(37, 99, 235, 0.14);
    animation: fadeIn 0.3s ease;
}

.meaning-label {
    font-size: 0.75rem;
    font-weight: 700;
    color: #2563eb;
    text-transform: uppercase;
}

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

.maijia-search-container {
    margin-top: calc(var(--spacing-xs) / 2);
    padding: var(--spacing-xs) var(--spacing-sm);
    background: #f0fdfa;
    border-radius: var(--radius-sm);
    display: flex;
    gap: var(--spacing-sm);
    align-items: center;
    border: 1px solid rgba(15, 118, 110, 0.14);
    animation: fadeIn 0.3s ease;
}

.maijia-search-container svg {
    color: #0f766e;
}

.maijia-search-container a {
    font-size: 0.875rem;
    color: #0f766e;
    text-decoration: none;
    font-weight: 500;
    transition: all var(--transition-fast);
}

.maijia-search-container a:hover {
    color: #0d9488;
    text-decoration: underline;
}

.expanded-terms-container {
    margin-top: calc(var(--spacing-xs) / 2);
    padding: var(--spacing-sm);
    background: #fff7ed;
    border-radius: var(--radius-sm);
    border: 1px solid rgba(234, 88, 12, 0.18);
    animation: fadeIn 0.3s ease;
}

.expanded-terms-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-xs);
}

.expanded-terms-label {
    font-size: 0.75rem;
    font-weight: 700;
    color: #c2410c;
}

.expanded-terms-list {
    display: flex;
    flex-wrap: wrap;
    gap: 0.375rem;
}

.expanded-term-chip,
.expanded-term-loading {
    display: inline-flex;
    align-items: center;
    min-height: 1.75rem;
    padding: 0.25rem 0.55rem;
    border-radius: var(--radius-sm);
    font-size: 0.78rem;
    line-height: 1.2;
}

.expanded-term-chip {
    color: #7c2d12;
    background: #ffedd5;
    border: 1px solid rgba(234, 88, 12, 0.16);
}

.expanded-term-loading {
    color: var(--text-muted);
}

.btn-expanded-search {
    flex-shrink: 0;
    padding: 0.35rem 0.65rem;
    border: 1px solid rgba(234, 88, 12, 0.28);
    border-radius: var(--radius-sm);
    color: #c2410c;
    background: #ffffff;
    font-size: 0.78rem;
    font-weight: 700;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.btn-expanded-search:hover:not(:disabled) {
    background: #fed7aa;
    border-color: rgba(234, 88, 12, 0.45);
}

.btn-expanded-search:disabled {
    cursor: not-allowed;
    opacity: 0.65;
}

.btn-search {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-md) var(--spacing-lg);
    background: var(--primary-gradient);
    border: none;
    border-radius: var(--radius-md);
    color: white;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
    box-shadow: var(--shadow-sm);
    margin-top: var(--spacing-sm);
}

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

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

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

/* ===== Loading State ===== */
.loading-state {
    text-align: center;
    padding: var(--spacing-xl);
}

.spinner {
    width: 48px;
    height: 48px;
    border: 4px solid rgba(37, 99, 235, 0.16);
    border-top-color: #2563eb;
    border-radius: 50%;
    margin: 0 auto var(--spacing-md);
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

.link-loader {
    width: 20px;
    height: 20px;
    border: 2px solid rgba(37, 99, 235, 0.16);
    border-top-color: #2563eb;
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
    margin-right: 12px;
}

.loading-fade {
    opacity: 0.7;
    pointer-events: none;
}

.link-status-container {
    display: flex;
    align-items: center;
    margin-top: 0.5rem;
    padding: 0.6rem 1rem;
    background: #eff6ff;
    border-radius: var(--radius-sm);
    border: 1px solid rgba(37, 99, 235, 0.16);
    animation: fadeIn 0.3s ease;
}

.link-status-container.error {
    background: #fff7ed;
    border-color: rgba(234, 88, 12, 0.28);
}

#linkStatusText {
    font-size: 0.8125rem;
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    gap: 10px;
}

.link-status-container.error #linkStatusText {
    color: #9a3412;
}

.status-dot {
    width: 6px;
    height: 6px;
    background-color: #2563eb;
    border-radius: 50%;
    display: inline-block;
    animation: pulse 1.5s ease infinite;
}

@keyframes pulse {
    0% {
        transform: scale(0.9);
        opacity: 1;
    }

    50% {
        transform: scale(1.3);
        opacity: 0.4;
    }

    100% {
        transform: scale(0.9);
        opacity: 1;
    }
}

.highlight-flash {
    animation: highlightFlash 1s ease;
}

@keyframes highlightFlash {
    0% {
        background-color: rgba(37, 99, 235, 0.12);
    }

    100% {
        background-color: transparent;
    }
}

/* ===== Error State ===== */
.error-state {
    text-align: center;
    padding: var(--spacing-xl);
    background: var(--bg-card);
    border: 1px solid rgba(239, 68, 68, 0.3);
    border-radius: var(--radius-lg);
    margin-bottom: var(--spacing-lg);
}

.error-state svg {
    margin-bottom: var(--spacing-md);
}

.error-state h3 {
    color: #ef4444;
    margin-bottom: var(--spacing-sm);
}

.error-state p {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
}

.btn-retry {
    padding: var(--spacing-sm) var(--spacing-lg);
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.3);
    border-radius: var(--radius-sm);
    color: #ef4444;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.btn-retry:hover {
    background: rgba(239, 68, 68, 0.2);
}

/* ===== Results Section ===== */
.results-section {
    animation: fadeIn 0.5s ease;
}

.results-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: var(--spacing-md);
    margin-bottom: 1.25rem;
}

.results-header h2 {
    font-size: 1.35rem;
    line-height: 1.3;
}

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

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.results-meta {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.cached-badge {
    padding: var(--spacing-xs) var(--spacing-sm);
    background: #eff6ff;
    border: 1px solid rgba(37, 99, 235, 0.16);
    border-radius: var(--radius-sm);
    color: #2563eb;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: none;
    letter-spacing: 0;
}

.result-count {
    padding: var(--spacing-xs) var(--spacing-md);
    background: #ecfdf5;
    border: 1px solid rgba(15, 118, 110, 0.16);
    border-radius: var(--radius-xl);
    font-size: 0.875rem;
    font-weight: 600;
    color: #0f766e;
}

.results-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-lg);
}

/* ===== Patent Card ===== */
.patent-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    overflow: hidden;
    transition: all var(--transition-normal);
    animation: slideUp 0.5s ease;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.patent-card:hover {
    box-shadow: var(--shadow-lg);
    border-color: rgba(37, 99, 235, 0.22);
}

.patent-image-container {
    position: relative;
    width: 100%;
    height: 240px;
    background: #f8fafc;
    overflow: hidden;
}

.patent-image {
    width: 100%;
    height: 100%;
    object-fit: contain;
    transition: transform var(--transition-slow);
}

.patent-card:hover .patent-image {
    transform: scale(1.02);
}

.image-placeholder {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
    height: 100%;
    color: var(--text-muted);
    font-size: 0.875rem;
}

.patent-content {
    padding: var(--spacing-md);
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.patent-card-header {
    display: grid;
    grid-template-columns: minmax(0, auto) minmax(0, 1fr);
    align-items: start;
    column-gap: 0.75rem;
    margin-bottom: var(--spacing-xs);
}

.patent-number {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    background: #eff6ff;
    border: 1px solid rgba(37, 99, 235, 0.18);
    border-radius: 99px;
    font-size: 0.9rem;
    font-weight: 600;
    color: #1d4ed8;
}

.patent-number-link:hover .patent-number {
    background: #2563eb;
    color: white;
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.22);
}

.patent-title {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    line-height: 1.4;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.patent-meta {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 0.15rem;
    font-size: 0.75rem;
    color: var(--text-muted);
    line-height: 1.35;
}

.patent-abstract {
    color: var(--text-secondary);
    font-size: 0.875rem;
    line-height: 1.6;
    display: -webkit-box;
    -webkit-line-clamp: 4;
    line-clamp: 4;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.risk-summary {
    border-top: 1px solid #eef2f7;
    margin-top: 0.25rem;
    padding-top: 0.75rem;
    display: grid;
    gap: 0.35rem;
}

.risk-summary strong {
    font-size: 0.82rem;
    color: var(--text-primary);
}

.risk-summary p {
    color: var(--text-secondary);
    font-size: 0.82rem;
    line-height: 1.55;
}

/* ===== History Sidebar ===== */
.history-sidebar {
    width: 320px;
    background: #ffffff;
    border-left: 1px solid var(--border-color);
    padding: var(--spacing-md);
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    z-index: 1000;
    display: flex;
    flex-direction: column;
    transition: transform var(--transition-normal);
    box-shadow: -10px 0 30px rgba(31, 41, 55, 0.14);
    transform: translateX(0);
}

.history-sidebar.hidden-sidebar {
    transform: translateX(100%);
}

.history-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(15, 23, 42, 0.34);
    backdrop-filter: blur(4px);
    z-index: 999;
    transition: opacity var(--transition-normal);
}

.history-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-md);
    padding-bottom: var(--spacing-sm);
    border-bottom: 1px solid var(--border-color);
}

.history-header h3 {
    font-size: 1.125rem;
    font-weight: 600;
}

.history-list {
    overflow-y: auto;
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.history-item {
    padding: var(--spacing-sm);
    background: #ffffff;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.history-item:hover {
    background: #f8fbff;
    border-color: #2563eb;
}

.history-item .history-item-main {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 4px;
}

.history-item .history-keyword {
    font-weight: 600;
    color: var(--text-primary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    flex: 1;
}

.history-count {
    background: var(--secondary-gradient);
    color: white;
    font-size: 0.7rem;
    font-weight: 700;
    padding: 2px 6px;
    border-radius: 10px;
    min-width: 18px;
    text-align: center;
    margin-left: var(--spacing-xs);
    box-shadow: none;
}

.history-item .history-meta {
    display: flex;
    justify-content: space-between;
    font-size: 0.75rem;
    color: var(--text-muted);
}

.history-empty {
    text-align: center;
    color: var(--text-muted);
    padding: var(--spacing-lg) 0;
    font-style: italic;
}

/* ===== Footer ===== */
.footer {
    padding: 2rem 0;
    border-top: 1px solid var(--border-color);
    color: var(--text-muted);
    font-size: 0.875rem;
}

.footer .container {
    display: flex;
    justify-content: space-between;
    gap: var(--spacing-md);
}

.footer-note {
    text-align: right;
}

.footer-nav {
    display: flex;
    flex-wrap: wrap;
    gap: 0.25rem 1rem;
    margin-top: 0.4rem;
}

.footer-nav a,
.guide-link a {
    color: #2563eb;
    text-decoration: none;
}

.footer-nav a:hover,
.guide-link a:hover {
    text-decoration: underline;
}

.logo-link {
    color: inherit;
    text-decoration: none;
}

.page-nav {
    display: flex;
    gap: 1rem;
    font-size: 0.875rem;
}

.page-nav a {
    color: var(--text-secondary);
    text-decoration: none;
}

.page-nav a:hover {
    color: #2563eb;
}

.legal-page {
    max-width: 820px;
    padding-top: 1rem;
    padding-bottom: 2rem;
}

.legal-page h1 {
    margin-bottom: 1rem;
    font-size: 2rem;
}

.legal-page h2 {
    margin: 2rem 0 0.7rem;
    font-size: 1.2rem;
}

.legal-page p,
.legal-page li {
    color: var(--text-secondary);
}

.legal-page ul,
.legal-page ol {
    padding-left: 1.4rem;
}

.legal-page li + li {
    margin-top: 0.4rem;
}

.legal-page a {
    color: #2563eb;
}

.eyebrow {
    color: var(--text-muted);
    font-size: 0.8125rem;
    margin-bottom: 0.5rem;
}

.lead {
    font-size: 1.05rem;
}

.knowledge-page,
.article-page {
    max-width: 900px;
}

.knowledge-page h1,
.article-page h1 {
    font-size: 2rem;
    margin-bottom: 0.75rem;
}

.knowledge-list {
    display: grid;
    gap: 1rem;
    margin-top: 2rem;
}

.knowledge-card {
    padding: 1.35rem;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
}

.knowledge-card h2 { font-size: 1.18rem; margin-bottom: 0.45rem; }
.knowledge-card h2 a { color: var(--text-primary); text-decoration: none; }
.knowledge-card h2 a:hover { color: #2563eb; }
.knowledge-card > p:not(.knowledge-meta) { color: var(--text-secondary); }
.knowledge-meta, .knowledge-loading, .knowledge-empty { color: var(--text-muted); font-size: 0.8125rem; }
.knowledge-read-more { display: inline-block; margin-top: 0.8rem; color: #2563eb; font-weight: 600; text-decoration: none; }
.article-summary { font-size: 1.1rem; color: var(--text-secondary); margin-bottom: 1.8rem; }
.article-body p { margin-bottom: 1.2rem; color: var(--text-secondary); }
.article-image { margin: 1.5rem 0; }
.article-image img { display: block; max-width: 100%; max-height: 680px; margin: 0 auto; border-radius: var(--radius-md); box-shadow: var(--shadow-sm); }
.article-image figcaption { margin-top: 0.5rem; color: var(--text-muted); text-align: center; font-size: 0.8125rem; }
.article-source { margin-top: 2rem; font-size: 0.875rem; }
.article-source a { color: #2563eb; }
.article-disclaimer { margin: 1.25rem 0; padding: 0.85rem 1rem; background: #f8fafc; border-left: 3px solid #94a3b8; color: var(--text-secondary); font-size: 0.875rem; }

.results-disclaimer {
    margin-top: 1.25rem;
    color: var(--text-muted);
    font-size: 0.8125rem;
}

.guide-section {
    margin-top: 2.5rem;
    padding: 1.75rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    background: var(--bg-card);
    box-shadow: var(--shadow-sm);
}

.guide-section h2 {
    font-size: 1.25rem;
    margin-bottom: 1rem;
}

.guide-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1rem;
}

.guide-grid article {
    padding: 1rem;
    border-radius: var(--radius-sm);
    background: #f8fafc;
}

.guide-grid h3 {
    font-size: 0.9375rem;
    margin-bottom: 0.4rem;
}

.guide-grid p,
.guide-link {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.guide-link {
    margin-top: 1rem;
}

/* ===== Utility Classes ===== */
.hidden {
    display: none !important;
}

/* ===== Responsive Design ===== */
@media (max-width: 768px) {
    .container {
        padding: 0 1rem;
    }

    .header {
        padding: 0.9rem 0;
    }

    .header-subtitle-container {
        margin-top: 0.15rem;
    }

    .main-content {
        padding: 1.5rem 0 2.25rem;
    }

    .layout-wrapper,
    .form-row {
        display: block;
    }

    .results-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }

    .guide-grid {
        grid-template-columns: 1fr;
    }

    .search-card {
        padding: 1.25rem;
    }

    .search-title {
        font-size: 1.5rem;
    }

    .seller-flow {
        grid-template-columns: 1fr;
        gap: 0.75rem;
        margin-top: 1.5rem;
        border-top: 0;
    }

    .seller-flow-item {
        display: grid;
        grid-template-columns: 32px minmax(0, 1fr);
        column-gap: 0.7rem;
        align-items: center;
        padding: 0.25rem 0;
        text-align: left;
    }

    .seller-flow-icon {
        position: static;
        transform: none;
        grid-row: span 2;
    }

    .seller-flow-item small {
        margin-top: 0.1rem;
    }

    .results-header {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-sm);
    }

    .results-meta {
        flex-wrap: wrap;
        gap: var(--spacing-sm);
    }

    .footer .container {
        display: block;
    }

    .footer-note {
        margin-top: 0.5rem;
        text-align: left;
    }

    .page-nav {
        gap: 0.65rem;
        font-size: 0.8125rem;
    }
}

@media (min-width: 769px) and (max-width: 1080px) {
    .results-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* ===== Custom Scrollbar ===== */
::-webkit-scrollbar {
    width: 10px;
}

::-webkit-scrollbar-track {
    background: #eef2f7;
}

::-webkit-scrollbar-thumb {
    background: #c6cfda;
    border-radius: 5px;
}

::-webkit-scrollbar-thumb:hover {
    background: #9aa7b7;
}

/* ===== Image Preview Modal ===== */
.image-modal {
    display: none;
    position: fixed;
    z-index: 1000;
    padding-top: 60px;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background-color: rgba(0, 0, 0, 0.9);
    backdrop-filter: blur(8px);
    cursor: zoom-out;
}

.modal-content {
    margin: auto;
    display: block;
    max-width: 90%;
    max-height: 85vh;
    border-radius: var(--radius-md);
    box-shadow: 0 0 40px rgba(0, 0, 0, 0.5);
    object-fit: contain;
    animation: zoomIn 0.3s ease;
    cursor: default;
}

@keyframes zoomIn {
    from {
        transform: scale(0.9);
        opacity: 0;
    }

    to {
        transform: scale(1);
        opacity: 1;
    }
}

.close-modal {
    position: absolute;
    top: 20px;
    right: 35px;
    color: #f1f1f1;
    font-size: 40px;
    font-weight: bold;
    transition: 0.3s;
    cursor: pointer;
    z-index: 1001;
}

.close-modal:hover,
.close-modal:focus {
    color: #bbb;
    text-decoration: none;
}

#caption {
    margin: auto;
    display: block;
    width: 80%;
    max-width: 700px;
    text-align: center;
    color: #e5e7eb;
    padding: 15px 0;
    font-size: 1rem;
}

/* Update patent image cursor */
.patent-image {
    cursor: zoom-in;
}

@keyframes highlightFlash {
    0% {
        background: rgba(37, 99, 235, 0.14);
    }

    100% {
        background: #ffffff;
    }
}

.highlight-flash {
    animation: highlightFlash 1s ease-out;
}

/* ===== AdSense Styling ===== */
.ad-container-results {
    grid-column: 1 / -1;
    margin: 0.25rem 0;
    padding: var(--spacing-sm);
    background: #f8fafc;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
    min-height: 90px;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.ad-label {
    font-size: 0.65rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 4px;
    text-align: center;
}