/* ==========================================
   MARKETRACE - B2B Solution Website Styles
   미니멀, 프리미엄, 전문가적 톤
   ========================================== */

/* ==========================================
   CSS Variables
   ========================================== */
:root {
    /* Colors */
    --color-primary: #1a1a2e;
    --color-secondary: #16213e;
    --color-accent: #0f3460;
    --color-text-primary: #1a1a1a;
    --color-text-secondary: #4a4a4a;
    --color-text-light: #6b6b6b;
    --color-bg-white: #ffffff;
    --color-bg-light: #f8f9fa;
    --color-bg-dark: #1a1a2e;
    --color-border: #e0e0e0;
    
    /* Typography */
    --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-weight-light: 300;
    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 4rem;
    --spacing-xl: 6rem;
    
    /* Layout */
    --max-width: 1200px;
    --border-radius: 4px;
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-primary);
    font-size: 16px;
    line-height: 1.7;
    color: var(--color-text-primary);
    background-color: var(--color-bg-white);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ==========================================
   Typography
   ========================================== */
h1, h2, h3, h4, h5, h6 {
    font-weight: var(--font-weight-semibold);
    line-height: 1.3;
    margin-bottom: var(--spacing-sm);
    color: var(--color-text-primary);
}

p {
    margin-bottom: var(--spacing-sm);
    color: var(--color-text-secondary);
}

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition-fast);
}

/* ==========================================
   Container & Layout
   ========================================== */
.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

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

.section-header {
    text-align: center;
    margin-bottom: var(--spacing-lg);
    max-width: 900px;
    margin-left: auto;
    margin-right: auto;
}

.section-title {
    font-size: 2.5rem;
    font-weight: var(--font-weight-semibold);
    margin-bottom: var(--spacing-md);
    line-height: 1.2;
}

.section-subtitle {
    font-size: 1.125rem;
    color: var(--color-text-secondary);
    line-height: 1.8;
}

/* ==========================================
   Navigation
   ========================================== */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background-color: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--color-border);
    z-index: 1000;
    transition: var(--transition-normal);
}

.nav-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.25rem 0;
}

.logo {
    font-size: 1.25rem;
    font-weight: var(--font-weight-bold);
    color: var(--color-primary);
    letter-spacing: -0.5px;
}

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

.nav-menu a {
    font-size: 0.9375rem;
    font-weight: var(--font-weight-medium);
    color: var(--color-text-secondary);
    transition: var(--transition-fast);
}

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

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 0.25rem;
    background: none;
    border: none;
    cursor: pointer;
}

.nav-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background-color: var(--color-text-primary);
    transition: var(--transition-fast);
}

/* ==========================================
   Buttons
   ========================================== */
.btn-primary,
.btn-primary-large,
.btn-secondary-large {
    display: inline-block;
    padding: 0.875rem 2rem;
    font-size: 0.9375rem;
    font-weight: var(--font-weight-medium);
    text-align: center;
    border-radius: var(--border-radius);
    transition: var(--transition-fast);
    cursor: pointer;
    border: none;
}

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

.btn-primary:hover,
.btn-primary-large:hover {
    background-color: var(--color-secondary);
    transform: translateY(-2px);
}

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

.btn-secondary-large:hover {
    background-color: var(--color-bg-light);
    border-color: var(--color-text-secondary);
}

.btn-primary-large {
    padding: 1rem 2.5rem;
    font-size: 1rem;
}

/* ==========================================
   Hero Section
   ========================================== */
.hero {
    padding: 10rem 0 8rem;
    background: linear-gradient(to bottom, #f8f9fa 0%, #ffffff 100%);
    margin-top: 70px;
}

.hero-content {
    text-align: center;
    max-width: 900px;
    margin: 0 auto;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: var(--font-weight-bold);
    margin-bottom: var(--spacing-md);
    letter-spacing: -1px;
    line-height: 1.2;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-lg);
    line-height: 1.8;
}

.hero-cta {
    display: flex;
    gap: 1rem;
    justify-content: center;
    align-items: center;
}

/* ==========================================
   Problem Section
   ========================================== */
.problem-section {
    background-color: var(--color-bg-white);
}

.problem-content {
    max-width: 800px;
    margin: 0 auto;
}

.problem-text {
    font-size: 1.125rem;
    line-height: 1.9;
    margin-bottom: var(--spacing-md);
    text-align: center;
}

.problem-conclusion {
    font-size: 1.25rem;
    font-weight: var(--font-weight-medium);
    color: var(--color-text-primary);
    text-align: center;
    margin-top: var(--spacing-lg);
    padding: var(--spacing-md);
    background-color: var(--color-bg-light);
    border-radius: var(--border-radius);
}

/* ==========================================
   Solution Section
   ========================================== */
.solution-section {
    background-color: var(--color-bg-light);
}

.solution-steps {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.step-card {
    background-color: var(--color-bg-white);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius);
    transition: var(--transition-normal);
    border: 1px solid var(--color-border);
}

.step-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
}

.step-number {
    font-size: 2.5rem;
    font-weight: var(--font-weight-bold);
    color: var(--color-accent);
    margin-bottom: var(--spacing-sm);
    opacity: 0.3;
}

.step-title {
    font-size: 1.5rem;
    margin-bottom: var(--spacing-sm);
}

.step-description {
    font-size: 1rem;
    line-height: 1.7;
}

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

.solution-value {
    font-size: 1.125rem;
    font-weight: var(--font-weight-medium);
    color: var(--color-text-primary);
}

/* ==========================================
   Data Section
   ========================================== */
.data-section {
    background-color: var(--color-bg-white);
}

.data-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.data-card {
    padding: var(--spacing-md);
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius);
    transition: var(--transition-normal);
}

.data-card:hover {
    border-color: var(--color-text-secondary);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
}

.data-card-title {
    font-size: 1.125rem;
    font-weight: var(--font-weight-semibold);
    margin-bottom: var(--spacing-sm);
}

.data-card-description {
    font-size: 0.9375rem;
    color: var(--color-text-light);
    line-height: 1.6;
}

.data-footer {
    text-align: center;
    padding: var(--spacing-md);
    background-color: var(--color-bg-light);
    border-radius: var(--border-radius);
}

.data-note {
    font-size: 1rem;
    color: var(--color-text-secondary);
}

/* ==========================================
   AI Section
   ========================================== */
.ai-section {
    background-color: var(--color-bg-dark);
    color: var(--color-bg-white);
}

.ai-section .section-title,
.ai-section .section-subtitle {
    color: var(--color-bg-white);
}

.ai-features {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.ai-feature {
    padding: var(--spacing-md);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: var(--border-radius);
    transition: var(--transition-normal);
}

.ai-feature:hover {
    background-color: rgba(255, 255, 255, 0.05);
    border-color: rgba(255, 255, 255, 0.4);
}

.ai-feature-title {
    font-size: 1.125rem;
    font-weight: var(--font-weight-medium);
    color: var(--color-bg-white);
}

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

.ai-conclusion {
    font-size: 1.125rem;
    color: rgba(255, 255, 255, 0.9);
    line-height: 1.8;
}

/* ==========================================
   Results Section
   ========================================== */
.results-section {
    background-color: var(--color-bg-light);
}

.results-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-md);
}

.result-card {
    text-align: center;
    padding: var(--spacing-md);
}

.result-title {
    font-size: 1.25rem;
    margin-bottom: var(--spacing-sm);
}

.result-description {
    font-size: 0.9375rem;
    color: var(--color-text-light);
}

/* ==========================================
   Target Section
   ========================================== */
.target-section {
    background-color: var(--color-bg-white);
}

.target-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-md);
}

.target-card {
    padding: var(--spacing-lg);
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius);
    transition: var(--transition-normal);
}

.target-card:hover {
    border-color: var(--color-text-secondary);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
}

.target-title {
    font-size: 1.25rem;
    margin-bottom: var(--spacing-sm);
}

.target-description {
    font-size: 1rem;
    color: var(--color-text-light);
}

/* ==========================================
   How to Use Section
   ========================================== */
.how-section {
    background-color: var(--color-bg-light);
}

.how-steps {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-md);
}

.how-step {
    text-align: center;
    padding: var(--spacing-md);
}

.how-step-number {
    display: inline-block;
    padding: 0.5rem 1rem;
    background-color: var(--color-primary);
    color: var(--color-bg-white);
    font-size: 0.875rem;
    font-weight: var(--font-weight-semibold);
    border-radius: var(--border-radius);
    margin-bottom: var(--spacing-sm);
}

.how-step-title {
    font-size: 1.25rem;
    margin-bottom: var(--spacing-sm);
}

.how-step-description {
    font-size: 0.9375rem;
    color: var(--color-text-light);
}

/* ==========================================
   FAQ Section
   ========================================== */
.faq-section {
    background-color: var(--color-bg-white);
}

.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    padding: var(--spacing-md);
    border-bottom: 1px solid var(--color-border);
}

.faq-item:last-child {
    border-bottom: none;
}

.faq-question {
    font-size: 1.125rem;
    font-weight: var(--font-weight-semibold);
    margin-bottom: var(--spacing-sm);
    color: var(--color-text-primary);
}

.faq-answer {
    font-size: 1rem;
    color: var(--color-text-secondary);
    line-height: 1.7;
}

/* ==========================================
   CTA Section
   ========================================== */
.cta-section {
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-secondary) 100%);
    color: var(--color-bg-white);
}

.cta-content {
    text-align: center;
    max-width: 700px;
    margin: 0 auto;
}

.cta-title {
    font-size: 2.5rem;
    font-weight: var(--font-weight-bold);
    color: var(--color-bg-white);
    margin-bottom: var(--spacing-md);
}

.cta-subtitle {
    font-size: 1.125rem;
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: var(--spacing-lg);
    line-height: 1.8;
}

.cta-form {
    background-color: var(--color-bg-white);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.15);
}

.form-group {
    margin-bottom: var(--spacing-sm);
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.875rem 1rem;
    font-size: 1rem;
    font-family: var(--font-primary);
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius);
    transition: var(--transition-fast);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--color-primary);
}

.form-group textarea {
    resize: vertical;
}

.cta-form button {
    width: 100%;
    margin-top: var(--spacing-sm);
}

/* ==========================================
   Footer
   ========================================== */
.footer {
    background-color: var(--color-bg-dark);
    color: var(--color-bg-white);
    padding: var(--spacing-lg) 0;
}

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

.footer-logo {
    font-size: 1.25rem;
    font-weight: var(--font-weight-bold);
    margin-bottom: var(--spacing-xs);
}

.footer-tagline {
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.7);
}

.footer-info p {
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.7);
}

/* ==========================================
   Responsive Design
   ========================================== */
@media (max-width: 992px) {
    .section-title {
        font-size: 2rem;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .solution-steps,
    .data-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .results-grid,
    .how-steps {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    /* Mobile Navigation */
    .nav-menu {
        position: fixed;
        top: 70px;
        left: 0;
        right: 0;
        background-color: var(--color-bg-white);
        flex-direction: column;
        padding: var(--spacing-md);
        box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: all 0.3s ease;
    }
    
    .nav-menu.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }
    
    .nav-menu li {
        margin: 0.5rem 0;
    }
    
    .nav-toggle {
        display: flex;
    }
    
    .nav-toggle.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }
    
    .nav-toggle.active span:nth-child(2) {
        opacity: 0;
    }
    
    .nav-toggle.active span:nth-child(3) {
        transform: rotate(-45deg) translate(5px, -5px);
    }
    
    .hero {
        padding: 6rem 0 4rem;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1rem;
    }
    
    .hero-cta {
        flex-direction: column;
    }
    
    .section {
        padding: var(--spacing-lg) 0;
    }
    
    .section-title {
        font-size: 1.75rem;
    }
    
    .solution-steps,
    .data-grid,
    .ai-features,
    .target-grid,
    .results-grid,
    .how-steps {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        flex-direction: column;
        text-align: center;
        gap: var(--spacing-md);
    }
}

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

.fade-in {
    animation: fadeIn 0.6s ease forwards;
}