/* ================================================================
   PDF Tools - Modern SaaS Design
   Clean, Fast, SEO-Optimized, Dark Mode Support
   ================================================================ */

:root {
    --primary: #3b82f6;
    --primary-dark: #1e40af;
    --accent: #8b5cf6;
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
    
    --bg-light: #ffffff;
    --bg-gray: #f9fafb;
    --text-dark: #1f2937;
    --text-gray: #6b7280;
    --text-light: #9ca3af;
    --border: #e5e7eb;
    
    --space-xs: 0.5rem;
    --space-sm: 0.75rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2rem;
    --space-2xl: 3rem;
    --space-3xl: 4rem;
    
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
    --shadow-md: 0 4px 6px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 15px rgba(0,0,0,0.1);
    --shadow-xl: 0 20px 25px rgba(0,0,0,0.1);
    
    --transition: 300ms cubic-bezier(0.4, 0, 0.2, 1);
}

@media (prefers-color-scheme: dark) {
    :root {
        --text-dark: #f9fafb;
        --text-gray: #d1d5db;
        --bg-light: #1f2937;
        --bg-gray: #111827;
        --border: #374151;
    }
}

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

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    color: var(--text-dark);
    background: var(--bg-light);
    line-height: 1.6;
    font-size: 1rem;
}

h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: var(--space-md);
    color: var(--text-dark);
}

h1 { font-size: 2.25rem; }
h2 { font-size: 1.875rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }

p {
    margin-bottom: var(--space-md);
    color: var(--text-gray);
    line-height: 1.8;
}

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

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

a:focus-visible {
    outline: 2px solid var(--primary);
    outline-offset: 2px;
}

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

.section {
    padding: var(--space-3xl) 0;
}

.section:nth-child(even) {
    background: var(--bg-gray);
}

/* ---- Header ---- */
header.header {
    background: var(--bg-light);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow-sm);
    transition: all var(--transition);
}

header.header.scrolled {
    box-shadow: var(--shadow-lg);
}

.header-wrapper {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-md) 0;
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    font-weight: 800;
    text-decoration: none;
    transition: transform var(--transition);
}

.logo-link {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    text-decoration: none;
    color: inherit;
}

.logo-icon {
    font-size: 1.75rem;
}

.logo-text {
    background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-size: 1.25rem;
}

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

.nav-menu {
    flex: 1;
    display: flex;
    justify-content: center;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: var(--space-xl);
    align-items: center;
    margin: 0;
    padding: 0;
}

.nav-item {
    position: relative;
}

.nav-link {
    font-weight: 500;
    color: var(--text-gray);
    transition: color var(--transition);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

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

/* Dropdown Toggle */
.dropdown-toggle {
    cursor: pointer;
    user-select: none;
}

.dropdown-toggle svg {
    transition: transform var(--transition);
    width: 16px;
    height: 16px;
}

.dropdown-toggle.active svg {
    transform: rotate(180deg);
}

/* Dropdown Menu */
.dropdown-menu {
    position: absolute;
    top: calc(100% + var(--space-md));
    left: 50%;
    transform: translateX(-50%);
    background: var(--bg-light);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    min-width: 280px;
    padding: var(--space-lg) 0;
    z-index: 1000;
    max-height: 500px;
    overflow-y: auto;
    display: none;
}

.dropdown-menu.active {
    display: block;
}

.nav-item:hover > .dropdown-menu {
    display: block;
}

.dropdown-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-md);
    padding: 0 var(--space-lg);
}

.dropdown-column {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.dropdown-item {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    padding: var(--space-sm) var(--space-md);
    color: var(--text-gray);
    text-decoration: none;
    border-radius: var(--radius-md);
    transition: all var(--transition);
}

.dropdown-item:hover {
    background: var(--bg-gray);
    color: var(--primary);
    padding-left: var(--space-lg);
}

.tool-icon {
    font-size: 1.25rem;
}

.tool-name {
    font-size: 0.875rem;
    font-weight: 500;
}

/* Mobile Menu Button */
.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: var(--space-xs);
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--space-md);
}

.mobile-menu-btn span {
    width: 24px;
    height: 2px;
    background: var(--text-dark);
    border-radius: var(--radius-sm);
    transition: all var(--transition);
}

.mobile-menu-btn.active span:nth-child(1) {
    transform: rotate(45deg) translateY(10px);
}

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

.mobile-menu-btn.active span:nth-child(3) {
    transform: rotate(-45deg) translateY(-10px);
}

/* Mobile Responsive */
@media (max-width: 768px) {
    .mobile-menu-btn {
        display: flex;
    }
    
    .nav-menu {
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        flex-direction: column;
        background: var(--bg-light);
        border-bottom: 1px solid var(--border);
        max-height: 0;
        overflow: hidden;
        transition: max-height var(--transition);
    }
    
    .nav-menu.active {
        max-height: 500px;
    }
    
    .nav-links {
        flex-direction: column;
        gap: 0;
        width: 100%;
        padding: var(--space-lg) 0;
    }
    
    .nav-item {
        width: 100%;
    }
    
    .nav-link {
        padding: var(--space-md) var(--space-lg);
        border-bottom: 1px solid var(--border);
        justify-content: space-between;
    }
    
    .dropdown-menu {
        position: static;
        transform: none;
        border: none;
        box-shadow: none;
        background: var(--bg-gray);
        border-left: 3px solid var(--primary);
        margin: 0;
        padding: var(--space-md) 0;
        top: auto;
        left: auto;
    }
    
    .dropdown-grid {
        grid-template-columns: 1fr;
        padding: 0;
    }
    
    .dropdown-item {
        padding: var(--space-md) var(--space-2xl);
    }
}

/* ---- Hero ---- */
.hero {
    background: linear-gradient(135deg, #1f2937 0%, #111827 100%);
    color: white;
    padding: var(--space-3xl) var(--space-lg);
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero-background {
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    z-index: 0;
}

.hero-decoration {
    position: absolute;
    border-radius: 50%;
    opacity: 0.15;
    animation: float 6s ease-in-out infinite;
}

.hero-decoration:nth-child(1) {
    width: 400px;
    height: 400px;
    background: rgba(59, 130, 246, 0.4);
    top: -100px;
    right: -100px;
    animation-delay: 0s;
}

.hero-decoration:nth-child(2) {
    width: 300px;
    height: 300px;
    background: rgba(139, 92, 246, 0.4);
    bottom: -50px;
    left: -50px;
    animation-delay: 1s;
}

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

.hero-content {
    position: relative;
    z-index: 1;
    max-width: 800px;
    margin: 0 auto;
}

.hero-title {
    color: white;
    margin-bottom: var(--space-md);
    font-size: clamp(2rem, 5vw, 3.5rem);
    font-weight: 800;
    line-height: 1.2;
}

.hero-subtitle {
    color: #d1d5db;
    font-size: clamp(1rem, 2vw, 1.25rem);
    max-width: 600px;
    margin: var(--space-lg) auto;
    line-height: 1.6;
}

.hero-cta {
    display: flex;
    gap: var(--space-md);
    justify-content: center;
    flex-wrap: wrap;
    margin-top: var(--space-2xl);
}

.hero-trust {
    color: #9ca3af;
    font-size: 0.875rem;
    margin-top: var(--space-xl);
    letter-spacing: 0.05em;
}

/* ---- Buttons ---- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
    padding: var(--space-sm) var(--space-lg);
    border: none;
    border-radius: var(--radius-lg);
    font-weight: 600;
    cursor: pointer;
    text-decoration: none;
    transition: all var(--transition);
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
    color: white;
    box-shadow: var(--shadow-md);
}

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

.btn-secondary {
    background: var(--bg-gray);
    color: var(--text-dark);
    border: 1px solid var(--border);
}

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

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

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

.btn-large {
    padding: var(--space-md) var(--space-2xl);
    font-size: 1.125rem;
}

.btn-lg {
    padding: var(--space-md) var(--space-2xl);
    font-size: 1.125rem;
}

.btn-sm,
.btn-small {
    padding: var(--space-xs) var(--space-md);
    font-size: 0.875rem;
}

/* ---- Cards ---- */
.card {
    background: var(--bg-light);
    border: 1px solid var(--border);
    border-radius: var(--radius-xl);
    padding: var(--space-xl);
    transition: all var(--transition);
}

.card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary);
}

.card-icon {
    font-size: 2.5rem;
    margin-bottom: var(--space-md);
}

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

.card-description {
    color: var(--text-gray);
    font-size: 0.95rem;
}

/* ---- Grid ---- */
.grid {
    display: grid;
    gap: var(--space-xl);
}

.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(240px, 1fr));
}

@media (max-width: 768px) {
    .grid-2, .grid-3, .grid-4 {
        grid-template-columns: 1fr;
    }
}

/* ---- Forms ---- */
.form-group {
    margin-bottom: var(--space-lg);
}

label {
    display: block;
    margin-bottom: var(--space-sm);
    font-weight: 600;
    color: var(--text-dark);
}

input, textarea, select {
    width: 100%;
    padding: var(--space-sm) var(--space-md);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    font-family: inherit;
    font-size: 1rem;
    transition: all var(--transition);
}

input:focus, textarea:focus, select:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.file-upload {
    border: 2px dashed var(--border);
    border-radius: var(--radius-xl);
    padding: var(--space-2xl);
    text-align: center;
    cursor: pointer;
    transition: all var(--transition);
    background: var(--bg-gray);
}

.file-upload:hover {
    border-color: var(--primary);
    background: rgba(59, 130, 246, 0.05);
}

.file-upload-icon {
    font-size: 2.5rem;
    margin-bottom: var(--space-md);
}

.file-upload-text {
    font-weight: 600;
    margin-bottom: var(--space-sm);
}

.file-upload-hint {
    font-size: 0.875rem;
    color: var(--text-light);
}

/* ---- Alerts ---- */
.alert {
    padding: var(--space-lg);
    border-radius: var(--radius-lg);
    margin-bottom: var(--space-md);
    display: flex;
    align-items: center;
    gap: var(--space-md);
}

.alert-success {
    background: rgba(16, 185, 129, 0.1);
    border: 1px solid var(--success);
    color: #047857;
}

.alert-error {
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid var(--danger);
    color: #991b1b;
}

.alert-warning {
    background: rgba(245, 158, 11, 0.1);
    border: 1px solid var(--warning);
    color: #92400e;
}

.alert-info {
    background: rgba(59, 130, 246, 0.1);
    border: 1px solid var(--primary);
    color: #1e40af;
}

/* ---- Footer ---- */
footer {
    background: linear-gradient(135deg, #1f2937 0%, #111827 100%);
    color: white;
    padding: var(--space-3xl) 0 var(--space-lg);
    margin-top: var(--space-3xl);
    border-top: 1px solid var(--border);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--space-2xl);
    margin-bottom: var(--space-2xl);
}

.footer-section h4 {
    color: white;
    margin-bottom: var(--space-md);
}

.footer-section a {
    display: block;
    color: #d1d5db;
    margin-bottom: var(--space-sm);
    transition: color var(--transition);
}

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

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: var(--space-lg);
    text-align: center;
    color: #9ca3af;
    font-size: 0.875rem;
}

/* ---- Breadcrumbs ---- */
.breadcrumbs {
    display: flex;
    gap: var(--space-sm);
    margin-bottom: var(--space-lg);
    font-size: 0.875rem;
}

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

/* ---- Utilities ---- */
.text-center { text-align: center; }
.mb-0 { margin-bottom: 0; }
.mb-1 { margin-bottom: var(--space-xs); }
.mb-2 { margin-bottom: var(--space-sm); }
.mb-3 { margin-bottom: var(--space-md); }
.mb-4 { margin-bottom: var(--space-lg); }

.mt-3 { margin-top: var(--space-md); }
.mt-4 { margin-top: var(--space-lg); }

.rounded { border-radius: var(--radius-lg); }
.flex { display: flex; }
.items-center { align-items: center; }

/* Spacing Utilities */
.gap-2 { gap: var(--space-sm); }
.gap-4 { gap: var(--space-md); }
.gap-6 { gap: var(--space-lg); }
.gap-8 { gap: var(--space-xl); }
.gap-12 { gap: var(--space-2xl); }

.mb-12 { margin-bottom: var(--space-2xl); }
.mb-8 { margin-bottom: var(--space-xl); }
.mb-6 { margin-bottom: var(--space-lg); }
.mb-4 { margin-bottom: var(--space-md); }

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

.hidden { display: none !important; }

@keyframes spin {
    to { transform: rotate(360deg); }
}

.spinner {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(59, 130, 246, 0.2);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@media print {
    header, footer { display: none; }
    body { background: white; color: black; }
}