/* ====================================
   Quick Merge - CSS Stylesheet
   Dark Theme with Yellow Accents
   ==================================== */

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

:root {
    /* Dark Theme Colors */
    --bg-primary: #0f0f0f;
    --bg-secondary: #1a1a1a;
    --bg-tertiary: #242424;
    --bg-card: #1e1e1e;
    
    /* Yellow Accent Colors */
    --accent-primary: #FFD700;
    --accent-secondary: #FFC107;
    --accent-hover: #FFEB3B;
    
    /* Text Colors */
    --text-primary: #ffffff;
    --text-secondary: #e0e0e0;
    --text-muted: #b0b0b0;
    --text-dark: #888888;
    
    /* Other Colors */
    --border-color: #333333;
    --success-color: #4CAF50;
    --error-color: #f44336;
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-xxl: 4rem;
    
    /* Border Radius */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    
    /* Shadows */
    --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-yellow: 0 4px 20px rgba(255, 215, 0, 0.2);
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-secondary);
    line-height: 1.6;
    font-size: 16px;
    overflow-x: hidden;
}

html {
    scroll-behavior: smooth;
}

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

a:hover {
    color: var(--accent-hover);
}

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

/* ============ Header & Navigation ============ */
.header {
    background-color: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: var(--shadow-sm);
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-sm) var(--spacing-md);
    height: 70px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--text-primary);
    cursor: pointer;
    transition: transform var(--transition-fast);
}

.logo:hover {
    transform: scale(1.05);
}

.logo a {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-primary);
}

.logo-icon {
    font-size: 1.8rem;
}

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

.highlight {
    color: var(--accent-primary);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: var(--spacing-lg);
    align-items: center;
}

.nav-link {
    color: var(--text-secondary);
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: var(--radius-sm);
    transition: all var(--transition-fast);
    position: relative;
}

.nav-link:hover {
    color: var(--accent-primary);
    background-color: rgba(255, 215, 0, 0.1);
}

.nav-link.active {
    color: var(--accent-primary);
    font-weight: 600;
}

.mobile-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: 10px;
    z-index: 1001;
}

.mobile-toggle span {
    width: 25px;
    height: 3px;
    background-color: var(--text-primary);
    transition: all var(--transition-fast);
    border-radius: 2px;
}

.mobile-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(8px, 8px);
}

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

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

/* ============ Hero Section ============ */
.hero {
    background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-tertiary) 100%);
    padding: var(--spacing-xxl) 0;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -50%;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle, rgba(255, 215, 0, 0.1) 0%, transparent 70%);
    animation: pulse 8s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 0.5; transform: scale(1); }
    50% { opacity: 0.8; transform: scale(1.1); }
}

.hero-content {
    position: relative;
    z-index: 1;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
    line-height: 1.2;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-muted);
    max-width: 700px;
    margin: 0 auto var(--spacing-lg);
}

.hero-features {
    display: flex;
    justify-content: center;
    gap: var(--spacing-lg);
    flex-wrap: wrap;
    margin-top: var(--spacing-lg);
}

.feature-badge {
    background-color: rgba(255, 215, 0, 0.15);
    color: var(--accent-primary);
    padding: 0.75rem 1.5rem;
    border-radius: 50px;
    font-weight: 600;
    font-size: 0.95rem;
    border: 2px solid rgba(255, 215, 0, 0.3);
    transition: all var(--transition-fast);
}

.feature-badge:hover {
    background-color: rgba(255, 215, 0, 0.25);
    transform: translateY(-2px);
    box-shadow: var(--shadow-yellow);
}

/* ============ PDF Tool Section ============ */
.tool-section {
    padding: var(--spacing-xxl) 0;
    background-color: var(--bg-primary);
}

.tool-container {
    background-color: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
    max-width: 900px;
    margin: 0 auto;
}

.tool-header {
    text-align: center;
    margin-bottom: var(--spacing-lg);
}

.tool-header h2 {
    font-size: 2rem;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
}

.tool-header p {
    color: var(--text-muted);
    font-size: 1.1rem;
}

.drop-zone {
    border: 3px dashed var(--border-color);
    border-radius: var(--radius-md);
    padding: var(--spacing-xxl);
    text-align: center;
    transition: all var(--transition-normal);
    background-color: var(--bg-secondary);
}

.drop-zone:hover,
.drop-zone.drag-over {
    border-color: var(--accent-primary);
    background-color: rgba(255, 215, 0, 0.05);
    transform: scale(1.01);
}

.drop-zone label {
    cursor: pointer;
    display: inline-flex;
}

.upload-icon {
    font-size: 4rem;
    margin-bottom: var(--spacing-md);
    opacity: 0.7;
}

.drop-text {
    font-size: 1.25rem;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
    font-weight: 600;
}

.or-text {
    color: var(--text-dark);
    margin: var(--spacing-md) 0;
    font-size: 0.95rem;
}

.file-info {
    color: var(--text-dark);
    font-size: 0.9rem;
    margin-top: var(--spacing-md);
}

/* File List */
.file-list {
    margin-top: var(--spacing-lg);
    display: none;
}

.file-list.active {
    display: block;
}

.file-item {
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    padding: var(--spacing-md);
    margin-bottom: var(--spacing-sm);
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: all var(--transition-fast);
    cursor: move;
}

.file-item:hover {
    background-color: var(--bg-tertiary);
    transform: translateX(5px);
}

.file-info-left {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.file-icon {
    font-size: 2rem;
}

.file-details {
    display: flex;
    flex-direction: column;
}

.file-name {
    color: var(--text-primary);
    font-weight: 600;
    font-size: 0.95rem;
}

.file-size {
    color: var(--text-dark);
    font-size: 0.85rem;
}

.file-remove {
    background-color: transparent;
    border: none;
    color: var(--error-color);
    font-size: 1.5rem;
    cursor: pointer;
    padding: 0.5rem;
    border-radius: var(--radius-sm);
    transition: all var(--transition-fast);
}

.file-remove:hover {
    background-color: rgba(244, 67, 54, 0.1);
    transform: scale(1.1);
}

/* Merge Section */
.merge-section {
    text-align: center;
    margin-top: var(--spacing-lg);
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--border-color);
}

.merge-info {
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-top: var(--spacing-sm);
}

/* Progress Section */
.progress-section {
    text-align: center;
    padding: var(--spacing-xl) 0;
}

.progress-bar {
    width: 100%;
    height: 8px;
    background-color: var(--bg-secondary);
    border-radius: 50px;
    overflow: hidden;
    margin-bottom: var(--spacing-md);
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--accent-secondary), var(--accent-primary));
    width: 0%;
    transition: width 0.3s ease;
    animation: progress 2s ease-in-out infinite;
}

@keyframes progress {
    0% { width: 0%; }
    50% { width: 70%; }
    100% { width: 100%; }
}

.progress-text {
    color: var(--text-muted);
    font-size: 0.95rem;
}

/* Download Section */
.download-section {
    text-align: center;
    padding: var(--spacing-xl) 0;
}

.success-icon {
    font-size: 4rem;
    color: var(--success-color);
    margin-bottom: var(--spacing-md);
    animation: scaleIn 0.5s ease;
}

@keyframes scaleIn {
    0% { transform: scale(0); }
    50% { transform: scale(1.1); }
    100% { transform: scale(1); }
}

.download-section h3 {
    color: var(--text-primary);
    font-size: 1.75rem;
    margin-bottom: var(--spacing-lg);
}

/* ============ Buttons ============ */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 1rem 2rem;
    border: none;
    border-radius: var(--radius-sm);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
    text-align: center;
    justify-content: center;
}

.btn-primary {
    background-color: var(--accent-primary);
    color: var(--bg-primary);
    box-shadow: var(--shadow-yellow);
}

.btn-primary:hover {
    background-color: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: 0 6px 24px rgba(255, 215, 0, 0.3);
}

.btn-merge {
    background: linear-gradient(135deg, var(--accent-secondary), var(--accent-primary));
    color: var(--bg-primary);
    font-size: 1.1rem;
    padding: 1.2rem 3rem;
    box-shadow: var(--shadow-yellow);
}

.btn-merge:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 30px rgba(255, 215, 0, 0.4);
}

.btn-download {
    background-color: var(--success-color);
    color: white;
    padding: 1.2rem 3rem;
    font-size: 1.1rem;
}

.btn-download:hover {
    background-color: #45a049;
    transform: translateY(-2px);
}

.btn-secondary {
    background-color: transparent;
    color: var(--text-secondary);
    border: 2px solid var(--border-color);
    margin-top: var(--spacing-md);
}

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

.btn-cta {
    background: linear-gradient(135deg, var(--accent-secondary), var(--accent-primary));
    color: var(--bg-primary);
    padding: 1.2rem 3rem;
    font-size: 1.2rem;
    box-shadow: var(--shadow-yellow);
}

.btn-cta:hover {
    transform: translateY(-3px) scale(1.05);
    box-shadow: 0 10px 35px rgba(255, 215, 0, 0.4);
}

.btn-icon {
    font-size: 1.2rem;
    transition: transform var(--transition-fast);
}

.btn:hover .btn-icon {
    transform: translateX(5px);
}

/* ============ Sections ============ */
section {
    position: relative;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--text-primary);
    text-align: center;
    margin-bottom: var(--spacing-md);
}

.section-subtitle {
    font-size: 1.15rem;
    color: var(--text-muted);
    text-align: center;
    margin-bottom: var(--spacing-xl);
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

/* ============ Benefits Section ============ */
.benefits-section {
    padding: var(--spacing-xxl) 0;
    background-color: var(--bg-secondary);
}

.benefits-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-xl);
}

.benefit-card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: var(--spacing-xl);
    text-align: center;
    transition: all var(--transition-normal);
}

.benefit-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-lg);
    border-color: var(--accent-primary);
}

.benefit-icon {
    font-size: 3.5rem;
    margin-bottom: var(--spacing-md);
    display: block;
}

.benefit-card h3 {
    font-size: 1.4rem;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

.benefit-card p {
    color: var(--text-muted);
    line-height: 1.7;
}

/* ============ How It Works Section ============ */
.how-it-works {
    padding: var(--spacing-xxl) 0;
    background-color: var(--bg-primary);
}

.steps-container {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: var(--spacing-lg);
    margin-top: var(--spacing-xl);
    flex-wrap: wrap;
}

.step {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: var(--spacing-xl);
    text-align: center;
    flex: 1;
    min-width: 250px;
    max-width: 300px;
    transition: all var(--transition-normal);
}

.step:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
    border-color: var(--accent-primary);
}

.step-number {
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, var(--accent-secondary), var(--accent-primary));
    color: var(--bg-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.75rem;
    font-weight: 800;
    margin: 0 auto var(--spacing-md);
    box-shadow: var(--shadow-yellow);
}

.step-content h3 {
    font-size: 1.3rem;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

.step-content p {
    color: var(--text-muted);
    line-height: 1.6;
}

.step-arrow {
    font-size: 2rem;
    color: var(--accent-primary);
    font-weight: bold;
}

/* ============ Content Section (SEO) ============ */
.content-section {
    padding: var(--spacing-xxl) 0;
    background-color: var(--bg-secondary);
}

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

.content-wrapper h2 {
    font-size: 2.2rem;
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
    margin-top: var(--spacing-xl);
}

.content-wrapper h2:first-child {
    margin-top: 0;
}

.content-wrapper h3 {
    font-size: 1.7rem;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
    margin-top: var(--spacing-lg);
}

.content-wrapper p {
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: var(--spacing-md);
    font-size: 1.05rem;
}

.content-wrapper strong {
    color: var(--accent-primary);
    font-weight: 600;
}

/* ============ Features Highlight ============ */
.features-section {
    padding: var(--spacing-xxl) 0;
    background-color: var(--bg-primary);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-md);
    margin-top: var(--spacing-xl);
}

.feature-item {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    padding: var(--spacing-md);
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-md);
    transition: all var(--transition-fast);
}

.feature-item:hover {
    background-color: var(--bg-tertiary);
    transform: translateX(5px);
    border-color: var(--accent-primary);
}

.feature-icon-small {
    font-size: 1.75rem;
    flex-shrink: 0;
}

.feature-item h4 {
    color: var(--text-primary);
    font-size: 1.05rem;
    margin-bottom: 0.25rem;
}

.feature-item p {
    color: var(--text-muted);
    font-size: 0.9rem;
    line-height: 1.5;
}

/* ============ Trust Section ============ */
.trust-section {
    padding: var(--spacing-xxl) 0;
    background-color: var(--bg-secondary);
}

.trust-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-xl);
}

.trust-card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: var(--spacing-xl);
    text-align: center;
    transition: all var(--transition-normal);
}

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

.trust-icon {
    font-size: 3rem;
    margin-bottom: var(--spacing-md);
    display: block;
}

.trust-card h3 {
    font-size: 1.3rem;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

.trust-card p {
    color: var(--text-muted);
    line-height: 1.7;
}

/* ============ FAQ Section ============ */
.faq-section {
    padding: var(--spacing-xxl) 0;
    background-color: var(--bg-primary);
}

.faq-container {
    max-width: 900px;
    margin: var(--spacing-xl) auto 0;
}

.faq-item {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-md);
    overflow: hidden;
    transition: all var(--transition-fast);
}

.faq-item:hover {
    border-color: var(--accent-primary);
}

.faq-question {
    padding: var(--spacing-md) var(--spacing-lg);
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    user-select: none;
}

.faq-question h3 {
    font-size: 1.15rem;
    color: var(--text-primary);
    font-weight: 600;
    flex: 1;
}

.faq-toggle {
    font-size: 1.5rem;
    color: var(--accent-primary);
    font-weight: bold;
    transition: transform var(--transition-fast);
    flex-shrink: 0;
    margin-left: var(--spacing-md);
}

.faq-item.active .faq-toggle {
    transform: rotate(45deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--transition-normal);
}

.faq-item.active .faq-answer {
    max-height: 500px;
}

.faq-answer p {
    padding: 0 var(--spacing-lg) var(--spacing-md);
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ============ CTA Section ============ */
.cta-section {
    padding: var(--spacing-xxl) 0;
    background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-tertiary) 100%);
    text-align: center;
    position: relative;
    overflow: hidden;
}

.cta-section::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255, 215, 0, 0.08) 0%, transparent 60%);
}

.cta-content {
    position: relative;
    z-index: 1;
}

.cta-content h2 {
    font-size: 2.5rem;
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
}

.cta-content p {
    font-size: 1.2rem;
    color: var(--text-muted);
    margin-bottom: var(--spacing-xl);
}

/* ============ Footer ============ */
.footer {
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    padding: var(--spacing-xxl) 0 var(--spacing-lg);
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
}

.footer-column {
    display: flex;
    flex-direction: column;
}

.footer-logo {
    display: flex;
    align-items: c