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

:root {
    --primary-color: #6366f1;
    --secondary-color: #8b5cf6;
    --text-color: #1f2937;
    --light-bg: #f9fafb;
    --border-color: #e5e7eb;
    --success-color: #10b981;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', sans-serif;
    color: var(--text-color);
    line-height: 1.6;
}

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

/* Header */
header {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    padding: 40px 0 20px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

header h1 {
    font-size: 2.5rem;
    margin-bottom: 8px;
}

header .tagline {
    font-size: 1.1rem;
    opacity: 0.95;
}

/* Navigation */
.navbar {
    background: white;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
    position: sticky;
    top: 0;
    z-index: 100;
}

.navbar ul {
    list-style: none;
    display: flex;
    gap: 2rem;
    padding: 1rem 0;
    flex-wrap: wrap;
}

.navbar a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: color 0.3s;
}

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

/* Hero Section */
.hero {
    padding: 60px 0;
    text-align: center;
    background: var(--light-bg);
}

.hero h2 {
    font-size: 2rem;
    margin-bottom: 1rem;
    color: var(--text-color);
}

.hero p {
    font-size: 1.1rem;
    color: #6b7280;
    margin-bottom: 2rem;
}

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

.btn {
    padding: 12px 28px;
    border-radius: 6px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
    display: inline-block;
}

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

.btn-primary:hover {
    background: #4f46e5;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}

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

.btn-secondary:hover {
    background: var(--light-bg);
    transform: translateY(-2px);
}

/* Features Section */
.features {
    padding: 60px 0;
}

.features h2 {
    font-size: 2rem;
    text-align: center;
    margin-bottom: 3rem;
}

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

.feature-card {
    padding: 2rem;
    background: var(--light-bg);
    border-radius: 8px;
    border-left: 4px solid var(--primary-color);
    transition: transform 0.3s, box-shadow 0.3s;
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.1);
}

.feature-card h3 {
    margin-bottom: 0.5rem;
    color: var(--primary-color);
    font-size: 1.2rem;
}

.feature-card p {
    color: #6b7280;
}

/* Protocols Section */
.protocols {
    padding: 60px 0;
    background: var(--light-bg);
}

.protocols h2 {
    font-size: 2rem;
    text-align: center;
    margin-bottom: 3rem;
}

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

.protocol-column h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
    font-size: 1.2rem;
}

.protocol-column ul {
    list-style: none;
}

.protocol-column li {
    padding: 0.5rem 0;
    color: #4b5563;
    border-bottom: 1px solid #e5e7eb;
}

.protocol-column li:last-child {
    border-bottom: none;
}

/* Requirements Section */
.requirements {
    padding: 60px 0;
}

.requirements h2 {
    font-size: 2rem;
    margin-bottom: 2rem;
}

.requirements h3 {
    color: var(--primary-color);
    margin-top: 1.5rem;
    margin-bottom: 1rem;
    font-size: 1.2rem;
}

.requirements ul {
    list-style: none;
    margin-bottom: 1.5rem;
}

.requirements li {
    padding: 0.75rem 0 0.75rem 2rem;
    position: relative;
}

.requirements li:before {
    content: "✓";
    position: absolute;
    left: 0;
    color: var(--success-color);
    font-weight: bold;
}

/* Documentation Section */
.documentation {
    padding: 60px 0;
    background: var(--light-bg);
}

.documentation h2 {
    font-size: 2rem;
    margin-bottom: 1.5rem;
}

.documentation > .container > p {
    margin-bottom: 2rem;
    color: #6b7280;
}

.doc-links {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 1rem;
}

.doc-link {
    padding: 12px 16px;
    background: white;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    text-decoration: none;
    color: var(--primary-color);
    font-weight: 500;
    transition: all 0.3s;
    text-align: center;
}

.doc-link:hover {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

/* Security Notice */
.security-notice {
    padding: 40px 0;
    background: #fef2f2;
}

.security-notice h3 {
    color: #dc2626;
    margin-bottom: 1rem;
}

.security-notice p {
    color: #7f1d1d;
    line-height: 1.8;
}

/* Footer */
footer {
    background: var(--text-color);
    color: white;
    padding: 20px 0;
    text-align: center;
    margin-top: 60px;
}

footer a {
    color: var(--primary-color);
    text-decoration: none;
}

footer a:hover {
    text-decoration: underline;
}

/* Responsive */
@media (max-width: 768px) {
    header h1 {
        font-size: 1.8rem;
    }

    .hero h2 {
        font-size: 1.5rem;
    }

    .features h2,
    .protocols h2,
    .requirements h2,
    .documentation h2 {
        font-size: 1.5rem;
    }

    .navbar ul {
        gap: 1rem;
    }

    .cta-buttons {
        flex-direction: column;
    }

    .btn {
        width: 100%;
        text-align: center;
    }
}
