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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    font-size: 16px;
    line-height: 1.625;
    color: #64748B;
    background-color: #F8FAFC;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Color System */
:root {
    /* Primary Colors */
    --primary-900: #0F172A;
    --primary-600: #2563EB;
    --primary-100: #DBEAFE;
    
    /* Secondary Colors */
    --secondary-500: #0D9488;
    --accent-500: #7C3AED;
    
    /* Neutral Scale */
    --neutral-50: #F8FAFC;
    --surface-white: #FFFFFF;
    --neutral-500: #64748B;
    --border-200: #E2E8F0;
    
    /* Semantic */
    --success: #10B981;
    --error: #EF4444;
}

/* Typography Scale */
.display-h1 {
    font-size: clamp(2.5rem, 5vw, 4rem);
    font-weight: 700;
    line-height: 1.125;
    letter-spacing: -0.02em;
    color: var(--primary-900);
    margin-bottom: 1.5rem;
}

.section-h2 {
    font-size: clamp(2rem, 4vw, 2.5rem);
    font-weight: 600;
    line-height: 1.2;
    letter-spacing: -0.01em;
    color: var(--primary-900);
    margin-bottom: 1rem;
}

.section-h3 {
    font-size: 1.5rem;
    font-weight: 600;
    line-height: 1.333;
    color: var(--primary-900);
    margin-bottom: 0.75rem;
}

.body-large {
    font-size: 1.25rem;
    line-height: 1.6;
    color: var(--neutral-500);
    margin-bottom: 1.5rem;
}

.caption-label {
    font-size: 0.875rem;
    font-weight: 500;
    line-height: 1.429;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    color: var(--neutral-500);
}

/* Layout System */
.container {
    max-width: 1240px;
    margin: 0 auto;
    padding: 0 2rem;
}

.section {
    padding: 6rem 0;
}

.section-spacing {
    margin-bottom: 6rem;
}

/* Grid System */
.grid {
    display: grid;
    gap: 2rem;
}

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

.grid-3 {
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.grid-4 {
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
}

/* Components */
.card {
    background: var(--surface-white);
    border: 1px solid #F1F5F9;
    border-radius: 8px;
    padding: 2rem;
    transition: all 0.3s ease;
}

.card:hover {
    transform: translateY(-4px);
    box-shadow: 0 10px 30px -5px rgba(37, 99, 235, 0.15);
    border-color: var(--primary-600);
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    height: 64px;
    padding: 0 2rem;
    font-weight: 600;
    font-size: 1rem;
    border-radius: 8px;
    border: none;
    cursor: pointer;
    transition: all 0.2s ease;
    text-decoration: none;
    min-width: 160px;
}

.btn-primary {
    background: var(--primary-600);
    color: white;
}

.btn-primary:hover {
    background: #1D4ED8;
    transform: scale(1.02);
}

.btn-secondary {
    background: transparent;
    color: var(--primary-600);
    border: 1px solid var(--primary-600);
}

.btn-secondary:hover {
    background: var(--primary-600);
    color: white;
}

/* Input Styles */
.input-group {
    display: flex;
    gap: 0;
    max-width: 500px;
    margin: 2rem auto;
}

.input {
    flex: 1;
    height: 64px;
    padding: 0 1.5rem;
    border: 1px solid var(--border-200);
    border-radius: 8px 0 0 8px;
    font-size: 1rem;
    font-family: inherit;
    background: var(--surface-white);
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.input:focus {
    outline: none;
    border-color: var(--primary-600);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.2);
}

.btn-input {
    border-radius: 0 8px 8px 0;
    white-space: nowrap;
}

/* Icon Styles */
.icon {
    width: 48px;
    height: 48px;
    color: var(--secondary-500);
    margin-bottom: 1rem;
}

.icon-primary {
    color: var(--primary-600);
}

/* Hero Section */
/* Header */
.header {
    background: var(--surface-white);
    border-bottom: 1px solid var(--border-200);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(10px);
}

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

.logo {
    height: 40px;
    width: auto;
}

.nav-links {
    display: flex;
    gap: 2rem;
    list-style: none;
    align-items: center;
}

.nav-links a {
    color: var(--primary-900);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s ease;
}

.nav-links a:hover {
    color: var(--primary-600);
}

.mobile-menu-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    color: var(--primary-900);
    cursor: pointer;
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, var(--neutral-50) 0%, var(--primary-100) 100%);
    min-height: 600px;
    display: flex;
    align-items: center;
    padding: 6rem 0;
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.hero-visual {
    display: flex;
    justify-content: center;
    align-items: center;
}

.trust-badge {
    background: var(--surface-white);
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    font-size: 0.875rem;
    color: var(--neutral-500);
    display: inline-block;
    margin-top: 2rem;
    border: 1px solid var(--border-200);
}

/* Statistics Cards */
.stat-card {
    text-align: center;
}

.stat-number {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--error);
    margin-bottom: 0.5rem;
}

.stat-text {
    font-size: 1.125rem;
    color: var(--neutral-500);
}

/* Industry Badges */
.industry-badge {
    background: var(--surface-white);
    border: 1px solid var(--border-200);
    border-radius: 8px;
    padding: 2rem;
    text-align: center;
    transition: all 0.3s ease;
    cursor: pointer;
}

.industry-badge:hover {
    border-color: var(--primary-600);
    transform: translateY(-2px);
}

.industry-badge svg {
    width: 48px;
    height: 48px;
    color: var(--neutral-400);
    margin-bottom: 1rem;
    transition: color 0.3s ease;
}

.industry-badge:hover svg {
    color: var(--primary-600);
}

.industry-label {
    font-weight: 600;
    color: var(--primary-900);
}

/* Platform Preview */
.platform-preview {
    background: var(--primary-900);
    color: white;
    border-radius: 12px;
    padding: 2.5rem;
    position: relative;
    overflow: hidden;
}

.platform-preview h2 {
    font-size: clamp(1.8rem, 4vw, 2.5rem);
    font-weight: 600;
    line-height: 1.2;
    margin-bottom: 1.5rem;
    color: white;
    text-wrap: balance;
}

.platform-features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

/* AI Models Section */
.ai-models-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin: 3rem 0;
}

.model-card {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    padding: 2rem;
    transition: all 0.3s ease;
    backdrop-filter: blur(10px);
}

.model-card:hover {
    transform: translateY(-4px);
    border-color: var(--primary-600);
    box-shadow: 0 20px 40px -10px rgba(0, 191, 255, 0.2);
}

.model-image {
    text-align: center;
    margin-bottom: 1.5rem;
}

.model-image img {
    width: 120px;
    height: 120px;
    object-fit: contain;
    filter: drop-shadow(0 4px 8px rgba(0, 191, 255, 0.3));
}

.model-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: white;
    margin-bottom: 0.5rem;
    text-align: center;
}

.model-subtitle {
    font-size: 0.875rem;
    color: var(--secondary-500);
    font-weight: 500;
    text-align: center;
    margin-bottom: 1rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.model-description {
    color: #94A3B8;
    line-height: 1.6;
    margin-bottom: 1.5rem;
    text-align: center;
}

.model-features {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    justify-content: center;
}

.feature-tag {
    background: rgba(0, 191, 255, 0.1);
    border: 1px solid rgba(0, 191, 255, 0.3);
    color: var(--primary-600);
    padding: 0.375rem 0.75rem;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 500;
    white-space: nowrap;
}

/* Training Process */
.training-process {
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    padding: 2.5rem;
    backdrop-filter: blur(10px);
}

.process-steps {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 2rem;
    flex-wrap: wrap;
}

.process-step {
    text-align: center;
    max-width: 200px;
}

.step-number {
    width: 40px;
    height: 40px;
    background: var(--primary-600);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 1.125rem;
    margin: 0 auto 1rem;
}

.process-step h4 {
    color: white;
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.process-step p {
    color: #94A3B8;
    font-size: 0.875rem;
    line-height: 1.5;
}

.process-arrow {
    color: var(--secondary-500);
    font-size: 1.5rem;
    font-weight: 300;
}

.coming-badge {
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    color: white;
    padding: 0.5rem 1rem;
    border-radius: 50px;
    font-size: 0.875rem;
    font-weight: 500;
    display: inline-block;
    margin-bottom: 1.5rem;
}

/* Articles Section */
.articles-section {
    padding: 4rem 0;
}

/* Filter Section */
.filter-section {
    padding: 2rem 0;
    background: var(--surface-white);
    border-bottom: 1px solid var(--border-200);
}

.filter-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    justify-content: center;
    align-items: center;
}

.filter-tag {
    padding: 0.625rem 1.25rem;
    border: 2px solid var(--border-200);
    border-radius: 50px;
    background: var(--surface-white);
    color: var(--neutral-500);
    font-weight: 500;
    font-size: 0.875rem;
    cursor: pointer;
    transition: all 0.3s ease;
    text-transform: capitalize;
}

.filter-tag:hover {
    border-color: var(--primary-600);
    color: var(--primary-600);
    transform: translateY(-2px);
}

.filter-tag:focus,
.filter-tag:focus-visible {
    outline: 2px solid var(--primary-600);
    outline-offset: 2px;
}

.filter-tag.active {
    background: var(--primary-600);
    border-color: var(--primary-600);
    color: white;
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
}

.article-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.article-tag {
    padding: 0.375rem 0.875rem;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.025em;
}

.tag-chatgpt {
    background: rgba(116, 195, 194, 0.15);
    color: #0D9488;
    border: 1px solid rgba(116, 195, 194, 0.3);
}

.tag-grok-ai {
    background: rgba(124, 58, 237, 0.15);
    color: #7C3AED;
    border: 1px solid rgba(124, 58, 237, 0.3);
}

.tag-research {
    background: rgba(37, 99, 235, 0.15);
    color: var(--primary-600);
    border: 1px solid rgba(37, 99, 235, 0.3);
}

.tag-law {
    background: rgba(239, 68, 68, 0.15);
    color: var(--error);
    border: 1px solid rgba(239, 68, 68, 0.3);
}

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

.article-card {
    background: var(--surface-white);
    border: 1px solid var(--border-200);
    border-radius: 12px;
    overflow: hidden;
    transition: all 0.3s ease;
    cursor: pointer;
    text-decoration: none;
    color: inherit;
    display: block;
}

.article-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 20px 40px -10px rgba(37, 99, 235, 0.2);
    border-color: var(--primary-600);
}

.article-image {
    width: 100%;
    height: 250px;
    object-fit: cover;
    background: linear-gradient(135deg, var(--primary-100) 0%, var(--primary-600) 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 4rem;
    color: white;
}

.article-content {
    padding: 2rem;
}

.article-title {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--primary-900);
    margin-bottom: 1rem;
    line-height: 1.3;
}

.article-summary {
    color: var(--neutral-500);
    line-height: 1.6;
    margin-bottom: 1rem;
}

.article-link {
    color: var(--primary-600);
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

.article-link i {
    width: 16px;
    height: 16px;
}

/* Footer */
.footer {
    background: var(--primary-900);
    color: white;
    padding: 3rem 0;
    margin-top: 4rem;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 3rem;
}

.footer-brand {
    max-width: 300px;
}

.footer-tagline {
    color: #94A3B8;
    margin: 1rem 0;
}

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

.footer-links li {
    margin-bottom: 0.75rem;
}

.footer-links a {
    color: #94A3B8;
    text-decoration: none;
    transition: color 0.2s ease;
}

.footer-links a:hover {
    color: white;
}

/* Animations */
.fade-in {
    opacity: 0;
    transform: translateY(20px);
    animation: fadeInUp 0.6s ease forwards;
}

@keyframes fadeInUp {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 0 1rem;
    }

    .section {
        padding: 4rem 0;
    }

    .nav-links {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--surface-white);
        padding: 1rem;
        border-bottom: 1px solid var(--border-200);
    }

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

    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 2rem;
    }

    .hero-visual {
        order: -1;
    }

    .grid-3,
    .grid-4 {
        grid-template-columns: 1fr;
    }

    .input-group {
        flex-direction: column;
        max-width: 100%;
    }

    .input {
        border-radius: 8px;
        margin-bottom: 1rem;
    }

    .btn-input {
        border-radius: 8px;
    }

    .footer-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .platform-features {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .ai-models-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .model-image img {
        width: 100px;
        height: 100px;
    }

    .process-steps {
        flex-direction: column;
        gap: 1.5rem;
    }

    .process-arrow {
        transform: rotate(90deg);
    }

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

    .filter-tags {
        gap: 0.75rem;
        padding: 0 0.5rem;
    }

    .filter-tag {
        padding: 0.5rem 1rem;
        font-size: 0.8125rem;
    }
}

/* Utility Classes */
.text-center {
    text-align: center;
}

.mb-0 {
    margin-bottom: 0;
}

.mb-1 {
    margin-bottom: 0.5rem;
}

.mb-2 {
    margin-bottom: 1rem;
}

.mb-3 {
    margin-bottom: 1.5rem;
}

.mt-2 {
    margin-top: 1rem;
}

.hidden {
    display: none;
}