/* =====================================================
   PDF Tools - Modern Premium Styling
   ===================================================== */

/* CSS Variables */
:root {
    --color-bg: #0f0f1a;
    --color-bg-light: #1a1a2e;
    --color-bg-card: #16162a;
    --color-primary: #6366f1;
    --color-primary-light: #818cf8;
    --color-primary-dark: #4f46e5;
    --color-secondary: #10b981;
    --color-accent: #f59e0b;
    --color-danger: #ef4444;
    --color-text: #f1f5f9;
    --color-text-muted: #94a3b8;
    --color-border: rgba(255, 255, 255, 0.1);
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --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);
    --transition: all 0.3s ease;
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

/* Reset & Base */
*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    background: var(--color-bg);
    color: var(--color-text);
    line-height: 1.6;
    min-height: 100vh;
}

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

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

/* App Container */
.app-container {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Header */
.header {
    background: rgba(15, 15, 26, 0.9);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--color-border);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-weight: 700;
    font-size: 1.25rem;
    color: var(--color-text);
}

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

.logo-icon {
    font-size: 1.5rem;
}

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

.nav-link:hover {
    color: var(--color-text);
    background: var(--color-bg-light);
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, var(--color-bg-light) 0%, var(--color-bg) 100%);
    padding: 4rem 2rem;
    text-align: center;
}

.hero-title {
    font-size: clamp(2rem, 5vw, 3.5rem);
    font-weight: 800;
    margin-bottom: 1rem;
    background: linear-gradient(135deg, var(--color-text) 0%, var(--color-primary-light) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--color-text-muted);
    max-width: 600px;
    margin: 0 auto;
}

/* Main Content */
.main-content {
    flex: 1;
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
    width: 100%;
}

/* Tools Grid */
.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
    margin-bottom: 4rem;
}

.tool-card {
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: 2rem;
    text-align: center;
    transition: var(--transition);
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

.tool-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--color-primary), var(--color-secondary));
    transform: scaleX(0);
    transition: var(--transition);
}

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

.tool-card:hover::before {
    transform: scaleX(1);
}

.tool-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
    display: block;
}

.tool-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--color-text);
}

.tool-desc {
    color: var(--color-text-muted);
    font-size: 0.9rem;
}

/* Tool Card Variants */
.tool-card--merge:hover {
    border-color: #6366f1;
}

.tool-card--split:hover {
    border-color: #ec4899;
}

.tool-card--extract:hover {
    border-color: #10b981;
}

.tool-card--delete:hover {
    border-color: #ef4444;
}

.tool-card--rotate:hover {
    border-color: #f59e0b;
}

.tool-card--images:hover {
    border-color: #06b6d4;
}

.tool-card--convert:hover {
    border-color: #8b5cf6;
}

/* Features Section */
.features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    padding: 3rem 0;
    border-top: 1px solid var(--color-border);
}

.feature {
    text-align: center;
}

.feature-icon {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.feature h4 {
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
}

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

/* Tool Page */
.tool-page {
    max-width: 700px;
    margin: 0 auto;
}

.tool-header {
    text-align: center;
    margin-bottom: 2rem;
}

.tool-header-icon {
    font-size: 4rem;
    margin-bottom: 1rem;
}

.tool-header h1 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.tool-header p {
    color: var(--color-text-muted);
}

/* Upload Area */
.upload-area {
    background: var(--color-bg-card);
    border: 2px dashed var(--color-border);
    border-radius: var(--radius-xl);
    padding: 3rem 2rem;
    text-align: center;
    transition: var(--transition);
    cursor: pointer;
}

.upload-area:hover,
.upload-area.dragover {
    border-color: var(--color-primary);
    background: rgba(99, 102, 241, 0.05);
}

.upload-icon {
    font-size: 4rem;
    margin-bottom: 1rem;
    opacity: 0.6;
}

.upload-text {
    font-size: 1.1rem;
    font-weight: 500;
    margin-bottom: 0.5rem;
}

.upload-subtext {
    color: var(--color-text-muted);
    margin-bottom: 1rem;
}

.upload-button {
    display: inline-block;
    background: var(--color-primary);
    color: white;
    padding: 0.75rem 2rem;
    border-radius: var(--radius-md);
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
}

.upload-button:hover {
    background: var(--color-primary-dark);
    transform: translateY(-2px);
}

.upload-hint {
    margin-top: 1rem;
    color: var(--color-text-muted);
    font-size: 0.85rem;
}

/* File Info */
.file-info {
    margin-top: 1.5rem;
}

.file-info-content {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    background: var(--color-bg-card);
    padding: 1rem 1.5rem;
    border-radius: var(--radius-md);
    border: 1px solid var(--color-border);
}

.file-info-name {
    font-weight: 500;
}

.file-info-size {
    color: var(--color-text-muted);
    font-size: 0.9rem;
}

.file-remove {
    background: transparent;
    border: none;
    color: var(--color-danger);
    cursor: pointer;
    font-size: 1.25rem;
    padding: 0.25rem;
    transition: var(--transition);
}

.file-remove:hover {
    transform: scale(1.2);
}

/* File List */
.file-list {
    margin-top: 1.5rem;
    background: var(--color-bg-card);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    border: 1px solid var(--color-border);
}

.file-list h3 {
    margin-bottom: 0.5rem;
}

.file-list-hint {
    color: var(--color-text-muted);
    font-size: 0.85rem;
    margin-bottom: 1rem;
}

.files {
    list-style: none;
}

.file-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.75rem 1rem;
    background: var(--color-bg-light);
    border-radius: var(--radius-sm);
    margin-bottom: 0.5rem;
    cursor: grab;
    transition: var(--transition);
}

.file-item:hover {
    background: rgba(99, 102, 241, 0.1);
}

.file-item.dragging {
    opacity: 0.5;
}

.file-item-name {
    font-weight: 500;
    flex: 1;
}

.file-item-size {
    color: var(--color-text-muted);
    font-size: 0.85rem;
    margin: 0 1rem;
}

.file-item-remove {
    background: transparent;
    border: none;
    color: var(--color-danger);
    cursor: pointer;
    font-size: 1.1rem;
    opacity: 0.7;
    transition: var(--transition);
}

.file-item-remove:hover {
    opacity: 1;
}

.add-more-btn {
    background: transparent;
    border: 1px dashed var(--color-border);
    color: var(--color-text-muted);
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius-md);
    cursor: pointer;
    width: 100%;
    margin-top: 0.5rem;
    transition: var(--transition);
}

.add-more-btn:hover {
    border-color: var(--color-primary);
    color: var(--color-primary);
}

/* Options Area */
.options-area {
    margin-top: 1.5rem;
    background: var(--color-bg-card);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    border: 1px solid var(--color-border);
}

.option-group {
    margin-bottom: 1rem;
}

.option-group:last-child {
    margin-bottom: 0;
}

.option-group label {
    display: block;
    font-weight: 500;
    margin-bottom: 0.5rem;
}

.option-hint {
    color: var(--color-text-muted);
    font-size: 0.85rem;
    margin-top: 0.5rem;
}

.text-input {
    width: 100%;
    padding: 0.75rem 1rem;
    background: var(--color-bg-light);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    color: var(--color-text);
    font-size: 1rem;
    transition: var(--transition);
}

.text-input:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.2);
}

.text-input::placeholder {
    color: var(--color-text-muted);
}

/* Radio Options */
.rotation-options,
.format-options {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.radio-option {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    cursor: pointer;
    padding: 0.5rem 1rem;
    background: var(--color-bg-light);
    border-radius: var(--radius-sm);
    transition: var(--transition);
}

.radio-option:hover {
    background: rgba(99, 102, 241, 0.1);
}

.radio-option input[type="radio"] {
    accent-color: var(--color-primary);
}

/* Action Area */
.action-area {
    margin-top: 2rem;
    text-align: center;
}

.action-button {
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
    color: white;
    border: none;
    padding: 1rem 3rem;
    font-size: 1.1rem;
    font-weight: 600;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition);
    min-width: 200px;
}

.action-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(99, 102, 241, 0.4);
}

.action-button:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

.action-button--danger {
    background: linear-gradient(135deg, var(--color-danger) 0%, #dc2626 100%);
}

.action-button--danger:hover {
    box-shadow: 0 8px 24px rgba(239, 68, 68, 0.4);
}

.btn-loading {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

/* Progress Area */
.progress-area {
    margin-top: 2rem;
    text-align: center;
}

.progress-bar {
    height: 8px;
    background: var(--color-bg-light);
    border-radius: 4px;
    overflow: hidden;
    margin-bottom: 1rem;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--color-primary), var(--color-secondary));
    border-radius: 4px;
    width: 0%;
    transition: width 0.3s ease;
    animation: progress-pulse 1.5s ease-in-out infinite;
}

@keyframes progress-pulse {

    0%,
    100% {
        opacity: 1;
    }

    50% {
        opacity: 0.7;
    }
}

.progress-text {
    color: var(--color-text-muted);
}

/* Result Area */
.result-area {
    margin-top: 2rem;
}

.result-success {
    background: var(--color-bg-card);
    border: 1px solid var(--color-secondary);
    border-radius: var(--radius-xl);
    padding: 2.5rem;
    text-align: center;
}

.result-icon {
    font-size: 4rem;
    margin-bottom: 1rem;
}

.result-success h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

.result-info {
    color: var(--color-text-muted);
    margin-bottom: 1.5rem;
}

.download-button {
    display: inline-block;
    background: linear-gradient(135deg, var(--color-secondary) 0%, #059669 100%);
    color: white;
    padding: 1rem 2.5rem;
    font-size: 1.1rem;
    font-weight: 600;
    border-radius: var(--radius-md);
    transition: var(--transition);
}

.download-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(16, 185, 129, 0.4);
    color: white;
}

.result-warning {
    margin-top: 1.5rem;
    color: var(--color-accent);
    font-size: 0.9rem;
}

.reset-button {
    display: inline-block;
    background: transparent;
    border: 1px solid var(--color-border);
    color: var(--color-text-muted);
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius-md);
    cursor: pointer;
    margin-top: 1rem;
    transition: var(--transition);
}

.reset-button:hover {
    border-color: var(--color-primary);
    color: var(--color-primary);
}

/* Error Area */
.error-area {
    margin-top: 2rem;
}

.error-content {
    background: var(--color-bg-card);
    border: 1px solid var(--color-danger);
    border-radius: var(--radius-xl);
    padding: 2.5rem;
    text-align: center;
}

.error-icon {
    font-size: 4rem;
    margin-bottom: 1rem;
}

.error-message {
    color: var(--color-danger);
    margin-bottom: 1.5rem;
}

/* Footer */
.footer {
    border-top: 1px solid var(--color-border);
    padding: 2rem;
    text-align: center;
    margin-top: auto;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
}

.footer p {
    color: var(--color-text-muted);
    font-size: 0.9rem;
}

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

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

    .hero {
        padding: 2rem 1rem;
    }

    .main-content {
        padding: 1rem;
    }

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

    .upload-area {
        padding: 2rem 1rem;
    }

    .action-button {
        width: 100%;
    }
}

/* Animations */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }

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

.tool-card,
.feature,
.result-area,
.error-area {
    animation: fadeIn 0.5s ease-out forwards;
}