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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #FFFFFF;
    color: #17191b;
    line-height: 1.7;
}

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

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 2rem 0;
    border-bottom: 2px solid #313c48;
    flex-wrap: wrap;
}

.logo-container {
    flex-shrink: 0;
}

.logo {
    width: 413px;
    height: 44px;
    object-fit: contain;
}

.main-nav {
    display: flex;
    gap: 1.5rem;
    flex-wrap: wrap;
}

.main-nav a {
    text-decoration: none;
    color: #17191b;
    font-weight: 600;
    transition: all 0.3s ease;
    padding: 0.5rem 1rem;
    border-radius: 5px;
    font-size: 0.9rem;
}

.main-nav a:hover {
    color: #313c48;
    background-color: rgba(49, 60, 72, 0.1);
    transform: translateY(-2px);
}

.hero {
    text-align: center;
    padding: 5rem 2rem;
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    margin: 2rem 0;
    border-radius: 20px;
}

.hero h1 {
    font-size: 2.8rem;
    margin-bottom: 1.5rem;
    background: linear-gradient(45deg, #17191b, #313c48);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    line-height: 1.2;
}

.subtitle {
    font-size: 1.3rem;
    color: #313c48;
    font-weight: 300;
    max-width: 800px;
    margin: 0 auto;
}

.links-section, .validator-section, .content-section, .faq-section {
    margin: 4rem 0;
    padding: 3rem;
    background: #f8f9fa;
    border-radius: 20px;
    box-shadow: 0 5px 15px rgba(23, 25, 27, 0.08);
}

.links-section h2, .validator-section h2, .content-section h2, .faq-section h2 {
    margin-bottom: 1.5rem;
    color: #17191b;
    font-size: 2.2rem;
    text-align: center;
}

.section-description {
    text-align: center;
    margin-bottom: 2rem;
    color: #313c48;
    font-size: 1.1rem;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

.links-container {
    display: grid;
    gap: 1.5rem;
    max-width: 900px;
    margin: 0 auto;
}

.link-card {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    border: 2px solid transparent;
    transition: all 0.4s ease;
    box-shadow: 0 3px 10px rgba(23, 25, 27, 0.05);
}

.link-card:hover {
    border-color: #313c48;
    transform: translateY(-5px);
    box-shadow: 0 15px 35px rgba(23, 25, 27, 0.15);
}

.link-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 2rem;
}

.link-url {
    word-break: break-all;
    font-family: 'Courier New', monospace;
    color: #313c48;
    flex: 1;
    font-size: 1.1rem;
    font-weight: 600;
}

.copy-btn {
    background: #17191b;
    color: white;
    border: none;
    padding: 0.8rem 1.5rem;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    flex-shrink: 0;
    font-weight: 600;
}

.copy-btn:hover {
    background: #313c48;
    transform: scale(1.05);
}

.validator-container {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    max-width: 700px;
    margin: 0 auto;
}

#linkInput {
    padding: 1.2rem;
    border: 2px solid #17191b;
    border-radius: 10px;
    font-size: 1.1rem;
    transition: all 0.3s ease;
    font-family: 'Courier New', monospace;
}

#linkInput:focus {
    outline: none;
    border-color: #313c48;
    box-shadow: 0 0 0 3px rgba(49, 60, 72, 0.1);
}

#validateBtn {
    background: #17191b;
    color: white;
    border: none;
    padding: 1.2rem 2.5rem;
    border-radius: 10px;
    cursor: pointer;
    font-size: 1.1rem;
    transition: all 0.3s ease;
    font-weight: 600;
}

#validateBtn:hover {
    background: #313c48;
    transform: translateY(-2px);
}

#validationResult {
    padding: 1.5rem;
    border-radius: 10px;
    font-weight: 600;
    text-align: center;
    font-size: 1.1rem;
}

.content-grid {
    display: grid;
    gap: 2rem;
    max-width: 900px;
    margin: 0 auto;
}

.text-content p {
    margin-bottom: 1.5rem;
    font-size: 1.1rem;
    line-height: 1.8;
}

.info-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2.5rem;
    margin: 3rem 0;
}

.info-card {
    background: white;
    padding: 2.5rem;
    border-radius: 15px;
    text-align: center;
    transition: all 0.4s ease;
    box-shadow: 0 5px 15px rgba(23, 25, 27, 0.08);
}

.info-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 15px 35px rgba(23, 25, 27, 0.15);
}

.info-card h3 {
    color: #17191b;
    margin-bottom: 1.5rem;
    font-size: 1.4rem;
}

.info-card p {
    color: #313c48;
    line-height: 1.7;
}

.security-grid, .guide-steps, .faq-grid {
    display: grid;
    gap: 2rem;
    max-width: 900px;
    margin: 0 auto;
}

.security-item, .step, .faq-item {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 3px 10px rgba(23, 25, 27, 0.05);
}

.security-item h3, .step h3, .faq-item h3 {
    color: #17191b;
    margin-bottom: 1rem;
    font-size: 1.3rem;
}

.support-content p {
    margin-bottom: 1.5rem;
    font-size: 1.1rem;
    line-height: 1.8;
    text-align: center;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

.faq-item h3 {
    color: #313c48;
    border-left: 4px solid #313c48;
    padding-left: 1rem;
}

footer {
    text-align: center;
    padding: 3rem 0;
    margin-top: 4rem;
    border-top: 2px solid #313c48;
    color: #313c48;
}

.footer-content p {
    margin-bottom: 0.5rem;
    font-weight: 500;
}

@media (max-width: 768px) {
    header {
        flex-direction: column;
        gap: 1.5rem;
    }
    
    .main-nav {
        justify-content: center;
    }
    
    .hero h1 {
        font-size: 2rem;
    }
    
    .subtitle {
        font-size: 1.1rem;
    }
    
    .link-content {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }
    
    .copy-btn {
        align-self: stretch;
    }
    
    .info-grid {
        grid-template-columns: 1fr;
    }
    
    .links-section, .validator-section, .content-section, .faq-section {
        padding: 2rem 1.5rem;
        margin: 2rem 0;
    }
}

@media (max-width: 480px) {
    .logo {
        width: 100%;
        height: auto;
        max-width: 300px;
    }
    
    .hero {
        padding: 3rem 1rem;
    }
    
    .hero h1 {
        font-size: 1.6rem;
    }
}