/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #818cf8;
    --secondary-color: #8b5cf6;
    --accent-color: #ec4899;
    --text-dark: #1e293b;
    --text-light: #64748b;
    --bg-light: #f8fafc;
    --bg-white: #ffffff;
    --border-color: #e2e8f0;
    --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);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--bg-white);
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Navbar */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    transition: all 0.3s ease;
}

.navbar.scrolled {
    box-shadow: var(--shadow-md);
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px 24px;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 20px;
    font-weight: 700;
    color: var(--text-dark);
}

.logo-icon {
    font-size: 28px;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 32px;
    align-items: center;
}

.nav-link {
    text-decoration: none;
    color: var(--text-light);
    font-weight: 500;
    font-size: 14px;
    transition: color 0.3s ease;
    position: relative;
}

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

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: width 0.3s ease;
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
}

.mobile-menu-toggle span {
    width: 24px;
    height: 2px;
    background: var(--text-dark);
    transition: all 0.3s ease;
}

/* Hero Section */
.hero {
    padding: 160px 0 120px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg width="60" height="60" viewBox="0 0 60 60" xmlns="http://www.w3.org/2000/svg"><g fill="none" fill-rule="evenodd"><g fill="%23ffffff" fill-opacity="0.05"><path d="M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z"/></g></g></svg>');
    opacity: 0.4;
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
    position: relative;
}

.hero-content {
    z-index: 2;
}

.hero-title {
    font-size: 56px;
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 24px;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.hero-subtitle {
    font-size: 20px;
    line-height: 1.6;
    opacity: 0.9;
    margin-bottom: 40px;
}

.hero-buttons {
    display: flex;
    gap: 16px;
}

.btn {
    padding: 14px 32px;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    font-size: 16px;
    transition: all 0.3s ease;
    display: inline-block;
}

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

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-xl);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.2);
    color: white;
    border: 2px solid white;
    backdrop-filter: blur(10px);
}

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

/* Hero Visual - Floating Cards */
.hero-visual {
    position: relative;
    height: 400px;
    z-index: 2;
}

.floating-card {
    position: absolute;
    background: rgba(255, 255, 255, 0.15);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.3);
    border-radius: 16px;
    padding: 24px;
    box-shadow: var(--shadow-xl);
    animation: float 6s ease-in-out infinite;
}

.floating-card .card-icon {
    font-size: 48px;
    margin-bottom: 12px;
}

.floating-card .card-text {
    font-size: 16px;
    font-weight: 600;
}

.card-1 {
    top: 20px;
    left: 40px;
    animation-delay: 0s;
}

.card-2 {
    top: 80px;
    right: 60px;
    animation-delay: 1.5s;
}

.card-3 {
    bottom: 100px;
    left: 20px;
    animation-delay: 3s;
}

.card-4 {
    bottom: 30px;
    right: 40px;
    animation-delay: 4.5s;
}

@keyframes float {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-20px);
    }
}

/* Sections */
.section {
    padding: 100px 0;
}

.section-alt {
    background: var(--bg-light);
}

.section-title {
    font-size: 48px;
    font-weight: 800;
    text-align: center;
    margin-bottom: 16px;
    color: var(--text-dark);
}

.section-description {
    font-size: 20px;
    text-align: center;
    color: var(--text-light);
    margin-bottom: 60px;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

/* Algorithm Grid */
.algorithm-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
    gap: 30px;
}

.algorithm-card {
    background: var(--bg-white);
    border-radius: 16px;
    padding: 32px;
    border: 1px solid var(--border-color);
    transition: all 0.3s ease;
    cursor: pointer;
}

.algorithm-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
    border-color: var(--primary-color);
}

.algorithm-card.featured {
    background: linear-gradient(135deg, #667eea15 0%, #764ba215 100%);
    border: 2px solid var(--primary-color);
}

.algorithm-header {
    display: flex;
    align-items: center;
    gap: 16px;
    margin-bottom: 16px;
}

.algorithm-icon {
    font-size: 48px;
    line-height: 1;
}

.algorithm-header h3 {
    font-size: 24px;
    font-weight: 700;
    color: var(--text-dark);
}

.algorithm-description {
    color: var(--text-light);
    margin-bottom: 20px;
    line-height: 1.7;
}

.algorithm-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 20px;
}

.tag {
    background: var(--primary-color);
    color: white;
    padding: 6px 14px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.algorithm-details {
    padding-top: 20px;
    border-top: 1px solid var(--border-color);
}

.algorithm-details strong {
    color: var(--text-dark);
    display: block;
    margin-bottom: 12px;
}

.algorithm-details ul {
    list-style: none;
    padding-left: 0;
}

.algorithm-details li {
    color: var(--text-light);
    padding: 6px 0;
    padding-left: 24px;
    position: relative;
}

.algorithm-details li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--primary-color);
    font-weight: bold;
}

/* Footer */
.footer {
    background: var(--text-dark);
    color: white;
    padding: 60px 0 30px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-section h4 {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 20px;
}

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

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

.footer-section li {
    margin-bottom: 12px;
}

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

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

.footer-bottom {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--text-light);
}

/* Responsive Design */
@media (max-width: 968px) {
    .hero .container {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .hero-visual {
        height: 300px;
    }

    .hero-title {
        font-size: 42px;
    }

    .algorithm-grid {
        grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
        gap: 24px;
    }

    .section-title {
        font-size: 36px;
    }
}

@media (max-width: 768px) {
    .nav-menu {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 24px;
        box-shadow: var(--shadow-lg);
        gap: 16px;
    }

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

    .mobile-menu-toggle {
        display: flex;
    }

    .mobile-menu-toggle.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }

    .mobile-menu-toggle.active span:nth-child(2) {
        opacity: 0;
    }

    .mobile-menu-toggle.active span:nth-child(3) {
        transform: rotate(-45deg) translate(7px, -6px);
    }

    .hero {
        padding: 120px 0 80px;
    }

    .hero-title {
        font-size: 32px;
    }

    .hero-subtitle {
        font-size: 16px;
    }

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

    .btn {
        text-align: center;
    }

    .hero-visual {
        display: none;
    }

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

    .section {
        padding: 60px 0;
    }

    .section-title {
        font-size: 28px;
    }

    .section-description {
        font-size: 16px;
    }
}

/* Smooth Scrolling */
html {
    scroll-behavior: smooth;
}

/* Selection */
::selection {
    background: var(--primary-color);
    color: white;
}

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

.algorithm-card {
    animation: fadeIn 0.5s ease-out;
}

.algorithm-card:nth-child(1) { animation-delay: 0.1s; }
.algorithm-card:nth-child(2) { animation-delay: 0.2s; }
.algorithm-card:nth-child(3) { animation-delay: 0.3s; }
.algorithm-card:nth-child(4) { animation-delay: 0.4s; }
.algorithm-card:nth-child(5) { animation-delay: 0.5s; }
.algorithm-card:nth-child(6) { animation-delay: 0.6s; }