/* ============================================
 Secure DNS Landing Page - Modern CSS
 Theme: Security & Privacy First
 ============================================ */


:root {
 
 --primary-color: #00d4ff;
 --primary-dark: #0099cc;
 --primary-light: #7dffff;
 --secondary-color: #7c3aed;
 --secondary-dark: #5b21b6;
 
 
 --bg-primary: #0a0e27;
 --bg-secondary: #131729;
 --bg-tertiary: #1a1f3a;
 --bg-card: #1e2540;
 --bg-card-hover: #252d4f;
 
 
 --text-primary: #ffffff;
 --text-secondary: #a0aec0;
 --text-tertiary: #718096;
 
 
 --accent-success: #10b981;
 --accent-warning: #f59e0b;
 --accent-danger: #ef4444;
 --accent-info: #3b82f6;
 
 
 --border-color: rgba(255, 255, 255, 0.1);
 --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
 --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.4);
 --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.5);
 --shadow-glow: 0 0 20px rgba(0, 212, 255, 0.3);
 
 
 --spacing-xs: 0.25rem;
 --spacing-sm: 0.5rem;
 --spacing-md: 1rem;
 --spacing-lg: 1.5rem;
 --spacing-xl: 2rem;
 --spacing-2xl: 3rem;
 --spacing-3xl: 4rem;
 
 
 --font-primary: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Inter', 'Roboto', sans-serif;
 --font-mono: 'SF Mono', 'Monaco', 'Cascadia Code', 'Roboto Mono', 'Courier New', monospace;
 
 
 --transition-fast: 150ms ease;
 --transition-base: 250ms ease;
 --transition-slow: 400ms ease;
}


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

html {
 scroll-behavior: smooth;
}

body {
 font-family: var(--font-primary);
 background: var(--bg-primary);
 color: var(--text-primary);
 line-height: 1.6;
 overflow-x: hidden;
}


.container {
 max-width: 1200px;
 margin: 0 auto;
 padding: 0 var(--spacing-lg);
}


.navbar {
 position: fixed;
 top: 0;
 left: 0;
 right: 0;
 z-index: 1000;
 background: rgba(10, 14, 39, 0.9);
 backdrop-filter: blur(10px);
 border-bottom: 1px solid var(--border-color);
 padding: var(--spacing-md) 0;
}

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

.nav-brand {
 display: flex;
 align-items: center;
 gap: var(--spacing-md);
 font-size: 1.5rem;
 font-weight: 700;
 color: var(--text-primary);
}

.logo-icon {
 color: var(--primary-color);
}

.nav-links {
 display: flex;
 align-items: center;
 gap: var(--spacing-xl);
}

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

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


.btn {
 display: inline-block;
 padding: 0.75rem 1.5rem;
 font-size: 1rem;
 font-weight: 600;
 text-decoration: none;
 border-radius: 0.5rem;
 transition: all var(--transition-base);
 cursor: pointer;
 border: none;
}

.btn-primary {
 background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
 color: var(--text-primary);
 box-shadow: var(--shadow-glow);
}

.btn-primary:hover {
 transform: translateY(-2px);
 box-shadow: 0 0 30px rgba(0, 212, 255, 0.5);
}

.btn-secondary {
 background: transparent;
 color: var(--primary-color);
 border: 2px solid var(--primary-color);
}

.btn-secondary:hover {
 background: var(--primary-color);
 color: var(--bg-primary);
}


.hero {
 position: relative;
 min-height: 100vh;
 display: flex;
 align-items: center;
 padding: var(--spacing-3xl) 0;
 overflow: hidden;
}

.hero-bg {
 position: absolute;
 top: 0;
 left: 0;
 right: 0;
 bottom: 0;
 background: 
 radial-gradient(circle at 20% 50%, rgba(124, 58, 237, 0.15), transparent 50%),
 radial-gradient(circle at 80% 50%, rgba(0, 212, 255, 0.15), transparent 50%);
 z-index: -1;
}

.hero-content {
 position: relative;
 z-index: 10;
 max-width: 800px;
 margin: 0 auto;
 text-align: center;
}

.hero-title {
 font-size: clamp(2.5rem, 5vw, 4rem);
 font-weight: 800;
 line-height: 1.2;
 margin-bottom: var(--spacing-lg);
 background: linear-gradient(135deg, var(--text-primary), var(--primary-light));
 -webkit-background-clip: text;
 -webkit-text-fill-color: transparent;
 background-clip: text;
}

.hero-subtitle {
 font-size: clamp(1.1rem, 2vw, 1.3rem);
 color: var(--text-secondary);
 margin-bottom: var(--spacing-2xl);
 line-height: 1.8;
}

.hero-actions {
 display: flex;
 gap: var(--spacing-lg);
 justify-content: center;
 flex-wrap: wrap;
 margin-bottom: var(--spacing-3xl);
}

.hero-stats {
 display: flex;
 justify-content: center;
 gap: var(--spacing-3xl);
 margin-top: var(--spacing-3xl);
}

.stat {
 text-align: center;
}

.stat-value {
 font-size: 2.5rem;
 font-weight: 800;
 color: var(--primary-color);
 line-height: 1;
 margin-bottom: var(--spacing-sm);
}

.stat-label {
 font-size: 0.9rem;
 color: var(--text-tertiary);
 text-transform: uppercase;
 letter-spacing: 1px;
}


section {
 padding: var(--spacing-3xl) 0;
}

.section-header {
 text-align: center;
 margin-bottom: var(--spacing-3xl);
}

.section-title {
 font-size: clamp(2rem, 4vw, 3rem);
 font-weight: 700;
 margin-bottom: var(--spacing-md);
 color: var(--text-primary);
}

.section-subtitle {
 font-size: 1.2rem;
 color: var(--text-secondary);
}


.features {
 background: var(--bg-secondary);
}

.features-grid {
 display: grid;
 grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
 gap: var(--spacing-xl);
}

.feature-card {
 background: var(--bg-card);
 border: 1px solid var(--border-color);
 border-radius: 1rem;
 padding: var(--spacing-xl);
 transition: all var(--transition-base);
 position: relative;
 overflow: hidden;
}

.feature-card::before {
 content: '';
 position: absolute;
 top: 0;
 left: 0;
 right: 0;
 height: 3px;
 background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
 opacity: 0;
 transition: opacity var(--transition-base);
}

.feature-card:hover {
 background: var(--bg-card-hover);
 transform: translateY(-5px);
 box-shadow: var(--shadow-lg);
}

.feature-card:hover::before {
 opacity: 1;
}

.feature-icon {
 width: 64px;
 height: 64px;
 margin-bottom: var(--spacing-lg);
 color: var(--primary-color);
}

.feature-title {
 font-size: 1.5rem;
 font-weight: 700;
 margin-bottom: var(--spacing-md);
 color: var(--text-primary);
}

.feature-description {
 color: var(--text-secondary);
 line-height: 1.7;
 margin-bottom: var(--spacing-lg);
}

.feature-badge {
 display: inline-block;
 padding: 0.25rem 0.75rem;
 background: rgba(0, 212, 255, 0.1);
 color: var(--primary-color);
 border: 1px solid var(--primary-color);
 border-radius: 2rem;
 font-size: 0.85rem;
 font-weight: 600;
 text-transform: uppercase;
 letter-spacing: 0.5px;
}


.specs {
 background: linear-gradient(180deg, var(--bg-primary), var(--bg-tertiary));
}

.specs-content {
 max-width: 900px;
 margin: 0 auto;
}

.specs-grid {
 display: grid;
 gap: var(--spacing-lg);
 margin-top: var(--spacing-2xl);
}

.spec-item {
 background: var(--bg-card);
 border: 1px solid var(--border-color);
 border-radius: 0.75rem;
 padding: var(--spacing-lg);
}

.spec-item label {
 display: block;
 font-size: 0.9rem;
 color: var(--text-tertiary);
 text-transform: uppercase;
 letter-spacing: 1px;
 margin-bottom: var(--spacing-sm);
}

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

.spec-value code {
 flex: 1;
 font-family: var(--font-mono);
 font-size: 1rem;
 color: var(--primary-light);
 background: rgba(0, 212, 255, 0.05);
 padding: var(--spacing-md);
 border-radius: 0.5rem;
 border: 1px solid rgba(0, 212, 255, 0.2);
}

.copy-btn {
 background: transparent;
 border: 1px solid var(--border-color);
 color: var(--text-secondary);
 padding: var(--spacing-sm);
 border-radius: 0.5rem;
 cursor: pointer;
 transition: all var(--transition-base);
}

.copy-btn:hover {
 background: var(--primary-color);
 color: var(--bg-primary);
 border-color: var(--primary-color);
}

.copy-btn.copied {
 background: var(--accent-success);
 border-color: var(--accent-success);
 color: white;
}


.how-to-use {
 background: var(--bg-secondary);
}

.tabs {
 max-width: 1000px;
 margin: 0 auto;
}

.tab-buttons {
 display: flex;
 gap: var(--spacing-sm);
 overflow-x: auto;
 padding-bottom: var(--spacing-md);
 margin-bottom: var(--spacing-xl);
 border-bottom: 2px solid var(--border-color);
}

.tab-btn {
 display: flex;
 align-items: center;
 gap: var(--spacing-sm);
 padding: var(--spacing-md) var(--spacing-lg);
 background: transparent;
 border: none;
 color: var(--text-secondary);
 font-size: 1rem;
 font-weight: 600;
 cursor: pointer;
 border-radius: 0.5rem;
 transition: all var(--transition-base);
 white-space: nowrap;
 position: relative;
}

.tab-btn::after {
 content: '';
 position: absolute;
 bottom: -0.75rem;
 left: 0;
 right: 0;
 height: 2px;
 background: var(--primary-color);
 opacity: 0;
 transition: opacity var(--transition-base);
}

.tab-btn:hover {
 color: var(--primary-color);
 background: rgba(0, 212, 255, 0.05);
}

.tab-btn.active {
 color: var(--primary-color);
}

.tab-btn.active::after {
 opacity: 1;
}

.tab-panel {
 display: none;
 animation: fadeIn var(--transition-slow);
}

.tab-panel.active {
 display: block;
}

@keyframes fadeIn {
 from {
 opacity: 0;
 transform: translateY(10px);
 }
 to {
 opacity: 1;
 transform: translateY(0);
 }
}

.tab-panel h3 {
 font-size: 1.8rem;
 margin-bottom: var(--spacing-xl);
 color: var(--text-primary);
}

.tab-panel h4 {
 font-size: 1.3rem;
 margin-bottom: var(--spacing-lg);
 margin-top: var(--spacing-xl);
 color: var(--primary-light);
}


.steps {
 display: flex;
 flex-direction: column;
 gap: var(--spacing-lg);
}

.step {
 display: flex;
 gap: var(--spacing-lg);
 background: var(--bg-card);
 border: 1px solid var(--border-color);
 border-radius: 0.75rem;
 padding: var(--spacing-lg);
 transition: all var(--transition-base);
}

.step:hover {
 background: var(--bg-card-hover);
 border-color: var(--primary-color);
}

.step-number {
 flex-shrink: 0;
 width: 40px;
 height: 40px;
 display: flex;
 align-items: center;
 justify-content: center;
 background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
 color: var(--text-primary);
 font-weight: 700;
 font-size: 1.2rem;
 border-radius: 50%;
}

.step-content {
 flex: 1;
}

.step-content h4 {
 font-size: 1.1rem;
 margin: 0 0 var(--spacing-sm) 0;
 color: var(--text-primary);
}

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

.step-content p:last-child {
 margin-bottom: 0;
}

.code-block {
 background: var(--bg-primary);
 border: 1px solid var(--border-color);
 border-radius: 0.5rem;
 padding: var(--spacing-md);
 margin: var(--spacing-md) 0;
}

.code-block code {
 font-family: var(--font-mono);
 font-size: 0.95rem;
 color: var(--primary-light);
 line-height: 1.6;
}

kbd {
 display: inline-block;
 padding: 0.2rem 0.5rem;
 font-family: var(--font-mono);
 font-size: 0.85rem;
 background: var(--bg-tertiary);
 border: 1px solid var(--border-color);
 border-radius: 0.25rem;
 box-shadow: 0 2px 0 rgba(0, 0, 0, 0.3);
}


.alert {
 padding: var(--spacing-md);
 border-radius: 0.5rem;
 margin-top: var(--spacing-lg);
 border-left: 4px solid;
}

.alert-info {
 background: rgba(59, 130, 246, 0.1);
 border-color: var(--accent-info);
 color: var(--text-secondary);
}

.alert-success {
 background: rgba(16, 185, 129, 0.1);
 border-color: var(--accent-success);
 color: var(--text-secondary);
}

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


.browser-section {
 margin-bottom: var(--spacing-2xl);
 padding-bottom: var(--spacing-xl);
 border-bottom: 1px solid var(--border-color);
}

.browser-section:last-child {
 border-bottom: none;
}


.footer {
 background: var(--bg-primary);
 border-top: 1px solid var(--border-color);
 padding: var(--spacing-3xl) 0 var(--spacing-xl) 0;
}

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

.footer-brand {
 display: flex;
 align-items: center;
 gap: var(--spacing-md);
 font-size: 1.5rem;
 font-weight: 700;
 margin-bottom: var(--spacing-md);
}

.footer-desc {
 color: var(--text-tertiary);
 line-height: 1.7;
}

.footer-section h4 {
 font-size: 1.1rem;
 margin-bottom: var(--spacing-md);
 color: var(--text-primary);
}

.footer-links {
 list-style: none;
}

.footer-links li {
 margin-bottom: var(--spacing-sm);
}

.footer-links a {
 color: var(--text-secondary);
 text-decoration: none;
 transition: color var(--transition-base);
}

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

.footer-bottom {
 text-align: center;
 padding-top: var(--spacing-xl);
 border-top: 1px solid var(--border-color);
 color: var(--text-tertiary);
}

.footer-powered {
 margin-top: var(--spacing-sm);
 font-size: 0.9rem;
}


@media (max-width: 768px) {
 .nav-links {
 gap: var(--spacing-md);
 }
 
 .nav-links a:not(.btn-primary) {
 display: none;
 }
 
 .hero {
 min-height: auto;
 padding: 6rem 0 var(--spacing-3xl) 0;
 }
 
 .hero-stats {
 flex-wrap: wrap;
 gap: var(--spacing-xl);
 }
 
 .hero-actions {
 flex-direction: column;
 }
 
 .hero-actions .btn {
 width: 100%;
 }
 
 .features-grid {
 grid-template-columns: 1fr;
 }
 
 .tab-buttons {
 flex-wrap: nowrap;
 overflow-x: scroll;
 }
 
 .step {
 flex-direction: column;
 }
 
 .footer-content {
 grid-template-columns: 1fr;
 }
}

@media (max-width: 480px) {
 :root {
 --spacing-xl: 1.5rem;
 --spacing-2xl: 2rem;
 --spacing-3xl: 2.5rem;
 }
 
 .container {
 padding: 0 var(--spacing-md);
 }
 
 .navbar {
 padding: var(--spacing-sm) 0;
 }
 
 .hero-title {
 font-size: 2rem;
 }
 
 .section-title {
 font-size: 1.8rem;
 }
}


.text-center {
 text-align: center;
}

.mt-0 { margin-top: 0}
.mt-1 { margin-top: var(--spacing-sm)}
.mt-2 { margin-top: var(--spacing-md)}
.mt-3 { margin-top: var(--spacing-lg)}

.mb-0 { margin-bottom: 0}
.mb-1 { margin-bottom: var(--spacing-sm)}
.mb-2 { margin-bottom: var(--spacing-md)}
.mb-3 { margin-bottom: var(--spacing-lg)}