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

:root {
    --primary-color: #6366f1;
    --primary-dark: #4f46e5;
    --secondary-color: #8b5cf6;
    --accent-color: #f59e0b;
    --bg-color: #ffffff;
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --text-light: #9ca3af;
    --border-color: #e5e7eb;
    --success-color: #10b981;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

html {
    scroll-behavior: smooth;
}

html.lockscreen {
    overflow: hidden;
}

.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    z-index: 1000;
    box-shadow: var(--shadow-lg);
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-xl);
}

img.lazy {
    opacity: 0;
    transition: opacity 0.3s ease-in-out;
}

img.lazy.loaded {
    opacity: 1;
}

.loading-spinner {
    border: 3px solid #f3f3f3;
    border-top: 3px solid var(--primary-color);
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: spin 1s linear infinite;
    margin: 0 auto;
}

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

.notification {
    position: fixed;
    top: 20px;
    right: 20px;
    padding: 16px 24px;
    border-radius: 8px;
    color: white;
    font-weight: 500;
    z-index: 1000;
    animation: slideIn 0.3s ease-out;
    box-shadow: var(--shadow-lg);
}

.notification-success {
    background: linear-gradient(135deg, var(--success-color), #059669);
}

.notification-error {
    background: linear-gradient(135deg, #ef4444, #dc2626);
}

@keyframes slideIn {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

.progress-container {
    width: 100%;
    height: 4px;
    background-color: #e5e7eb;
    border-radius: 2px;
    margin-top: 16px;
    overflow: hidden;
}

.progress-bar {
    height: 100%;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    border-radius: 2px;
    transition: width 0.3s ease-out;
}

.fade-in {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-color);
}

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

.navbar {
    background-color: var(--bg-color);
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 100;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px 20px;
}

.logo a {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    text-decoration: none;
}

.logo-icon {
    font-size: 1.8rem;
    color: var(--primary-color);
}

.logo-text {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    transition: color 0.2s;
}

.nav-links a:hover {
    color: var(--primary-color);
}

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background-color: var(--text-primary);
    margin: 3px 0;
    transition: 0.3s;
}

.hero {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
    padding: 80px 0;
    text-align: center;
}

.hero h1 {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 1rem;
    line-height: 1.2;
}

.hero-subtitle {
    font-size: 1.25rem;
    opacity: 0.95;
    margin-bottom: 2rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.cta-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 12px 24px;
    border-radius: 8px;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.2s;
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

.btn-primary {
    background-color: white;
    color: var(--primary-color);
}

.btn-primary:hover {
    background-color: rgba(255, 255, 255, 0.9);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-secondary {
    background-color: rgba(255, 255, 255, 0.15);
    color: white;
    border: 1px solid rgba(255, 255, 255, 0.3);
}

.btn-secondary:hover {
    background-color: rgba(255, 255, 255, 0.25);
}

.btn-full {
    width: 100%;
}

.features-preview {
    padding: 60px 0;
}

.features-preview h2 {
    text-align: center;
    font-size: 2rem;
    margin-bottom: 40px;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.feature-card {
    background-color: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: var(--shadow-sm);
    text-align: center;
    transition: transform 0.2s, box-shadow 0.2s;
}

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

.feature-icon {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.feature-card h3 {
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.feature-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.watermark-tool {
    padding: 60px 0;
    background-color: #f9fafb;
}

.watermark-tool h2 {
    text-align: center;
    font-size: 2rem;
    margin-bottom: 0.5rem;
}

.tool-description {
    text-align: center;
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.tool-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    max-width: 900px;
    margin: 0 auto;
}

.upload-section {
    background-color: white;
    border-radius: 12px;
    padding: 2rem;
    box-shadow: var(--shadow-sm);
}

.upload-area {
    border: 2px dashed var(--border-color);
    border-radius: 8px;
    padding: 3rem;
    text-align: center;
    cursor: pointer;
    transition: border-color 0.2s, background-color 0.2s;
}

.upload-area:hover {
    border-color: var(--primary-color);
    background-color: #f0f9ff;
}

.upload-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.upload-hint {
    font-size: 0.875rem;
    color: var(--text-light);
    margin-top: 0.5rem;
}

.upload-limit {
    font-size: 0.75rem;
    color: var(--text-light);
    margin-top: 0.75rem;
    background-color: #f3f4f6;
    padding: 8px 12px;
    border-radius: 4px;
    display: inline-block;
}

.file-list {
    margin-top: 1rem;
    max-height: 200px;
    overflow-y: auto;
}

.file-item {
    display: flex;
    align-items: center;
    padding: 8px;
    border-radius: 6px;
    background-color: #f9fafb;
    margin-bottom: 8px;
}

.file-item img {
    width: 40px;
    height: 40px;
    object-fit: cover;
    border-radius: 4px;
    margin-right: 10px;
}

.file-item span {
    flex: 1;
    font-size: 0.875rem;
    color: var(--text-secondary);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.settings-section {
    background-color: white;
    border-radius: 12px;
    padding: 2rem;
    box-shadow: var(--shadow-sm);
}

.settings-section h3 {
    margin-bottom: 1.5rem;
    color: var(--text-primary);
}

.setting-group {
    margin-bottom: 1.5rem;
}

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

.setting-group input[type="text"],
.setting-group input[type="range"],
.setting-group input[type="color"],
.setting-group select {
    width: 100%;
    padding: 10px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 1rem;
}

.setting-group input[type="color"] {
    padding: 2px;
    height: 40px;
}

.setting-group input[type="range"] {
    padding: 0;
}

.setting-group select {
    cursor: pointer;
}

.preview-section {
    margin-top: 2rem;
}

.preview-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 1rem;
}

.preview-card {
    background-color: white;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: var(--shadow-sm);
}

.preview-card img {
    width: 100%;
    height: 150px;
    object-fit: cover;
}

.preview-card .actions {
    padding: 8px;
    display: flex;
    gap: 8px;
}

.preview-card .btn {
    flex: 1;
    padding: 6px 8px;
    font-size: 0.75rem;
}

.testimonials {
    padding: 60px 0;
}

.testimonials h2 {
    text-align: center;
    font-size: 2rem;
    margin-bottom: 40px;
}

.testimonials-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.testimonial-card {
    background-color: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: var(--shadow-sm);
}

.testimonial-card p {
    margin-bottom: 1.5rem;
    color: var(--text-secondary);
    font-style: italic;
}

.author {
    display: flex;
    align-items: center;
}

.avatar {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    margin-right: 12px;
}

.author .name {
    display: block;
    font-weight: 600;
    color: var(--text-primary);
}

.author .role {
    display: block;
    font-size: 0.875rem;
    color: var(--text-light);
}

.footer {
    background-color: var(--text-primary);
    color: white;
    padding: 40px 0;
    margin-top: 60px;
}

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

.footer-section h4 {
    margin-bottom: 1rem;
}

.footer-section p {
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.9rem;
}

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

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

.footer-section ul li a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    transition: color 0.2s;
}

.footer-section ul li a:hover {
    color: white;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 1rem;
    text-align: center;
    color: rgba(255, 255, 255, 0.5);
    font-size: 0.875rem;
}

.page-hero {
    background: linear-gradient(135deg, #f9fafb 0%, #f3f4f6 100%);
    padding: 60px 0;
    text-align: center;
}

.page-hero h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.page-hero p {
    color: var(--text-secondary);
    font-size: 1.1rem;
}

.features-list {
    padding: 60px 0;
}

.feature-item {
    display: grid;
    grid-template-columns: 1fr 3fr;
    gap: 2rem;
    align-items: center;
    padding: 3rem 0;
    border-bottom: 1px solid var(--border-color);
}

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

.feature-item.reverse {
    grid-template-columns: 3fr 1fr;
}

.feature-item.reverse .feature-icon-large {
    order: 2;
}

.feature-icon-large {
    font-size: 4rem;
    text-align: center;
}

.feature-content h2 {
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.feature-content p {
    color: var(--text-secondary);
    line-height: 1.8;
}

.pricing-section {
    padding: 60px 0;
    background-color: #f9fafb;
    text-align: center;
}

.pricing-section h2 {
    font-size: 2rem;
    margin-bottom: 0.5rem;
}

.pricing-description {
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.pricing-card {
    background-color: white;
    border-radius: 12px;
    padding: 2rem;
    max-width: 400px;
    margin: 0 auto;
    box-shadow: var(--shadow-md);
}

.pricing-card h3 {
    margin-bottom: 0.5rem;
}

.price {
    font-size: 3rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 1.5rem;
}

.pricing-card ul {
    list-style: none;
    margin-bottom: 2rem;
    text-align: left;
}

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

.pricing-card ul li:last-child {
    border-bottom: none;
}

.about-content {
    padding: 60px 0;
}

.about-section {
    margin-bottom: 2rem;
}

.about-section h2 {
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.about-section p {
    color: var(--text-secondary);
    line-height: 1.8;
}

.stats-section {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    margin: 40px 0;
}

.stat-card {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    padding: 2rem;
    border-radius: 12px;
    text-align: center;
}

.stat-number {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.stat-label {
    opacity: 0.9;
}

.user-types {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-top: 1.5rem;
}

.user-card {
    background-color: #f9fafb;
    padding: 1.5rem;
    border-radius: 8px;
    text-align: center;
}

.user-icon {
    font-size: 2rem;
    margin-bottom: 0.5rem;
}

.user-card h3 {
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.user-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.commitment-list {
    list-style: none;
    margin-top: 1rem;
}

.commitment-list li {
    padding: 0.75rem 0;
    border-bottom: 1px solid var(--border-color);
    color: var(--text-secondary);
}

.commitment-list li:last-child {
    border-bottom: none;
}

.privacy-content {
    padding: 60px 0;
    max-width: 800px;
    margin: 0 auto;
}

.privacy-section {
    margin-bottom: 2rem;
}

.privacy-section h2 {
    margin-bottom: 1rem;
    color: var(--text-primary);
    font-size: 1.25rem;
}

.privacy-section p {
    color: var(--text-secondary);
    line-height: 1.8;
}

.privacy-section ul {
    margin-left: 1.5rem;
    color: var(--text-secondary);
}

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

.blog-content {
    padding: 60px 0;
}

.blog-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.blog-card {
    background-color: white;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: transform 0.2s, box-shadow 0.2s;
}

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

.blog-card .blog-meta {
    padding: 1rem 1.5rem;
    display: flex;
    gap: 1rem;
    font-size: 0.875rem;
    color: var(--text-light);
}

.category {
    background-color: var(--primary-color);
    color: white;
    padding: 2px 8px;
    border-radius: 4px;
    font-size: 0.75rem;
}

.blog-card h2 {
    padding: 0 1.5rem;
    margin-bottom: 0.5rem;
    font-size: 1.25rem;
    color: var(--text-primary);
}

.blog-card p {
    padding: 0 1.5rem;
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.read-more {
    display: inline-block;
    margin: 0 1.5rem 1.5rem;
    color: var(--primary-color);
    font-weight: 500;
    text-decoration: none;
    transition: color 0.2s;
}

.read-more:hover {
    color: var(--primary-dark);
}

.blog-image {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.pagination-section {
    margin-top: 40px;
    text-align: center;
}

.pagination {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    flex-wrap: wrap;
}

.pagination-btn {
    padding: 10px 16px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    background-color: white;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all 0.2s;
    font-size: 0.9rem;
}

.pagination-btn:hover:not(:disabled) {
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.pagination-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.pagination-numbers {
    display: flex;
    gap: 4px;
}

.pagination-number {
    width: 36px;
    height: 36px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    background-color: white;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all 0.2s;
    font-size: 0.9rem;
}

.pagination-number:hover:not(.active) {
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.pagination-number.active {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
    color: white;
}

.pagination-info {
    margin-top: 16px;
    color: var(--text-light);
    font-size: 0.875rem;
}

.blog-article {
    padding: 60px 0;
}

.article-content {
    max-width: 800px;
    margin: 0 auto;
}

.article-header {
    margin-bottom: 2rem;
}

.meta-info {
    display: flex;
    gap: 1rem;
    font-size: 0.875rem;
    color: var(--text-light);
}

.meta-info .category {
    background-color: var(--primary-color);
    color: white;
    padding: 4px 12px;
    border-radius: 4px;
    font-size: 0.75rem;
}

.blog-article h2 {
    font-size: 1.75rem;
    margin-top: 2rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.blog-article h3 {
    font-size: 1.25rem;
    margin-top: 1.5rem;
    margin-bottom: 0.75rem;
    color: var(--text-primary);
}

.blog-article p {
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: 1rem;
}

.blog-article ul,
.blog-article ol {
    margin-left: 1.5rem;
    color: var(--text-secondary);
    margin-bottom: 1rem;
}

.blog-article ul li,
.blog-article ol li {
    margin-bottom: 0.5rem;
    line-height: 1.6;
}

.blog-article strong {
    color: var(--text-primary);
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 60px;
        left: 0;
        width: 100%;
        background-color: white;
        padding: 1rem;
        box-shadow: var(--shadow-md);
    }

    .nav-links.active {
        display: flex;
    }

    .hamburger {
        display: flex;
    }

    .hero h1 {
        font-size: 2rem;
    }

    .hero-subtitle {
        font-size: 1rem;
    }

    .tool-container {
        grid-template-columns: 1fr;
    }

    .feature-item {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .feature-item.reverse {
        grid-template-columns: 1fr;
    }

    .feature-item.reverse .feature-icon-large {
        order: 1;
    }

    .feature-icon-large {
        margin-bottom: 1rem;
    }

    .features-grid,
    .testimonials-grid,
    .blog-grid {
        grid-template-columns: 1fr;
    }

    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
}