:root {
    --primary-color: #2563eb;
    --primary-dark: #1e40af;
    --primary-light: #3b82f6;
    --secondary-color: #10b981;
    --danger-color: #ef4444;
    --warning-color: #f59e0b;
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --text-light: #9ca3af;
    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --bg-tertiary: #f3f4f6;
    --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);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
}

/* Navigation */
.navbar {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-md);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
    text-decoration: none;
}

.logo-icon {
    font-size: 2rem;
}

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

.nav-link {
    color: var(--text-primary);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
    padding: 0.5rem 1rem;
    border-radius: 0.5rem;
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary-color);
    background: var(--bg-tertiary);
}

.nav-right {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.lang-selector {
    padding: 0.5rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    background: var(--bg-primary);
    color: var(--text-primary);
    cursor: pointer;
    font-size: 1rem;
    transition: all 0.3s;
}

.lang-selector:hover {
    border-color: var(--primary-color);
    box-shadow: var(--shadow-sm);
}

/* Hero Section */
.hero {
    text-align: center;
    padding: 3rem 2rem;
    color: white;
}

.hero h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    font-weight: 700;
}

.hero-subtitle {
    font-size: 1.25rem;
    opacity: 0.9;
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
}

/* Main IP Section */
.ip-main-section {
    margin-bottom: 3rem;
}

.ip-main-card {
    background: white;
    border-radius: 1rem;
    padding: 3rem;
    box-shadow: var(--shadow-xl);
    text-align: center;
}

.ip-main-card h2 {
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
    color: var(--text-secondary);
}

.ip-display {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 1rem;
    flex-wrap: wrap;
}

.ip-address {
    font-size: 3rem;
    font-weight: 700;
    color: var(--primary-color);
    font-family: 'Courier New', monospace;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.1);
}

.ip-type {
    display: inline-block;
    padding: 0.5rem 1rem;
    background: var(--secondary-color);
    color: white;
    border-radius: 2rem;
    font-weight: 600;
    font-size: 0.875rem;
}

.btn-copy {
    padding: 0.75rem 1.5rem;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 0.5rem;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 600;
    transition: all 0.3s;
    box-shadow: var(--shadow-md);
}

.btn-copy:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

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

/* Info Grid */
.info-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 1.5rem;
    margin-bottom: 3rem;
}

.info-card {
    background: white;
    border-radius: 1rem;
    padding: 2rem;
    box-shadow: var(--shadow-lg);
    transition: all 0.3s;
}

.info-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-xl);
}

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

.info-card h3 {
    font-size: 1.25rem;
    margin-bottom: 1.5rem;
    color: var(--text-primary);
    border-bottom: 2px solid var(--primary-color);
    padding-bottom: 0.5rem;
}

.info-content {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.info-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.5rem 0;
}

.info-label {
    font-weight: 600;
    color: var(--text-secondary);
}

.info-value {
    color: var(--text-primary);
    font-weight: 500;
    text-align: right;
    word-break: break-word;
    max-width: 60%;
}

.info-value.small-text {
    font-size: 0.75rem;
    line-height: 1.4;
}

/* About Section */
.about-section {
    background: white;
    border-radius: 1rem;
    padding: 3rem;
    box-shadow: var(--shadow-lg);
    margin-bottom: 3rem;
}

.about-section h2 {
    font-size: 2rem;
    margin-bottom: 1.5rem;
    color: var(--primary-color);
}

.about-content {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.about-content p {
    font-size: 1.1rem;
    line-height: 1.8;
    color: var(--text-secondary);
}

/* API Section */
.api-section {
    background: white;
    border-radius: 1rem;
    padding: 3rem;
    box-shadow: var(--shadow-lg);
    margin-bottom: 3rem;
}

.api-section h2 {
    font-size: 2rem;
    margin-bottom: 1.5rem;
    color: var(--primary-color);
}

.api-content p {
    font-size: 1.1rem;
    line-height: 1.8;
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.api-example {
    background: var(--bg-tertiary);
    border-radius: 0.5rem;
    padding: 1.5rem;
    margin-top: 1rem;
}

.api-example h3 {
    font-size: 1.1rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.api-example pre {
    background: #1f2937;
    color: #10b981;
    padding: 1rem;
    border-radius: 0.5rem;
    overflow-x: auto;
    margin-bottom: 1.5rem;
}

.api-example code {
    font-family: 'Courier New', monospace;
    font-size: 0.9rem;
}

/* FAQ Section */
.faq-section {
    background: white;
    border-radius: 1rem;
    padding: 3rem;
    box-shadow: var(--shadow-lg);
    margin-bottom: 3rem;
}

.faq-section h2 {
    font-size: 2rem;
    margin-bottom: 2rem;
    color: var(--primary-color);
    text-align: center;
}

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

.faq-item {
    padding: 1.5rem;
    background: var(--bg-secondary);
    border-radius: 0.5rem;
    transition: all 0.3s;
}

.faq-item:hover {
    background: var(--bg-tertiary);
    transform: translateY(-2px);
}

.faq-item h4 {
    color: var(--primary-color);
    margin-bottom: 0.75rem;
    font-size: 1.1rem;
}

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

/* Footer */
.footer {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    padding: 3rem 2rem 1rem;
    margin-top: 4rem;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h4 {
    margin-bottom: 1rem;
    color: var(--primary-color);
}

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

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

.footer-section a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: color 0.3s;
}

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

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

/* Responsive */
@media (max-width: 768px) {
    .nav-container {
        flex-direction: column;
        gap: 1rem;
    }

    .nav-menu {
        flex-direction: column;
        gap: 0.5rem;
        text-align: center;
    }

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

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

    .ip-address {
        font-size: 2rem;
    }

    .ip-main-card {
        padding: 2rem 1rem;
    }

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

    .info-value {
        max-width: 50%;
        font-size: 0.9rem;
    }

    .about-section,
    .api-section,
    .faq-section {
        padding: 2rem 1rem;
    }

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

/* Loading Animation */
@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.5;
    }
}

.loading {
    animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
}

/* Success Animation */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in {
    animation: fadeIn 0.5s ease-out;
}