/* ============================================
   RESET & BASE STYLES
   ============================================ */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Colors */
    --primary: #667eea;
    --primary-dark: #5568d3;
    --secondary: #764ba2;
    --accent: #f093fb;
    --success: #4ade80;
    --warning: #fbbf24;
    --danger: #f87171;
    
    /* Background */
    --bg-primary: #0f0f23;
    --bg-secondary: #1a1a2e;
    --bg-card: rgba(26, 26, 46, 0.6);
    --bg-card-hover: rgba(26, 26, 46, 0.8);
    
    /* Text */
    --text-primary: #ffffff;
    --text-secondary: #a0aec0;
    --text-muted: #718096;
    
    /* Border */
    --border-color: rgba(255, 255, 255, 0.1);
    --border-radius: 16px;
    --border-radius-sm: 8px;
    
    /* Shadow */
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.2);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.3);
    --shadow-glow: 0 0 30px rgba(102, 126, 234, 0.3);
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    
    /* Font */
    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-heading: 'Outfit', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

body {
    font-family: var(--font-body);
    background: linear-gradient(135deg, #0f0f23 0%, #1a1a2e 50%, #16213e 100%);
    background-attachment: fixed;
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    overflow-x: hidden;
}

/* Animated background particles */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: 
        radial-gradient(circle at 20% 30%, rgba(102, 126, 234, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 70%, rgba(118, 75, 162, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 50% 50%, rgba(240, 147, 251, 0.05) 0%, transparent 50%);
    pointer-events: none;
    z-index: -1;
}

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

/* ============================================
   HEADER
   ============================================ */
.header {
    text-align: center;
    margin-bottom: var(--spacing-xl);
    animation: fadeInDown 0.6s ease-out;
}

.logo {
    font-family: var(--font-heading);
    font-size: 2.5rem;
    font-weight: 800;
    background: linear-gradient(135deg, var(--primary), var(--secondary), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-sm);
}

.tagline {
    color: var(--text-secondary);
    font-size: 1.1rem;
}

/* ============================================
   UPLOAD SECTION
   ============================================ */
.upload-section {
    margin-bottom: var(--spacing-lg);
    animation: fadeInUp 0.6s ease-out 0.2s both;
}

.dropzone {
    background: var(--bg-card);
    backdrop-filter: blur(20px);
    border: 2px dashed var(--border-color);
    border-radius: var(--border-radius);
    padding: var(--spacing-xl);
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.dropzone::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1), rgba(118, 75, 162, 0.1));
    opacity: 0;
    transition: opacity 0.3s ease;
}

.dropzone:hover,
.dropzone.drag-over {
    border-color: var(--primary);
    background: var(--bg-card-hover);
    box-shadow: var(--shadow-glow);
    transform: translateY(-2px);
}

.dropzone:hover::before,
.dropzone.drag-over::before {
    opacity: 1;
}

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

.upload-icon {
    color: var(--primary);
    margin-bottom: var(--spacing-md);
    animation: float 3s ease-in-out infinite;
}

.dropzone h2 {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    margin-bottom: var(--spacing-xs);
    color: var(--text-primary);
}

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

.file-types {
    display: inline-block;
    background: rgba(102, 126, 234, 0.2);
    color: var(--primary);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--border-radius-sm);
    font-size: 0.875rem;
    font-weight: 600;
}

/* ============================================
   SETTINGS PANEL
   ============================================ */
.settings-panel {
    background: var(--bg-card);
    backdrop-filter: blur(20px);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
    animation: fadeInUp 0.6s ease-out 0.3s both;
}

.settings-panel h3 {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.settings-grid {
    display: grid;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-md);
}

.setting-item {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.setting-item label {
    font-weight: 600;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.setting-item small {
    color: var(--text-muted);
    font-size: 0.875rem;
}

/* Slider */
.slider {
    width: 100%;
    height: 6px;
    border-radius: 3px;
    background: var(--bg-secondary);
    outline: none;
    -webkit-appearance: none;
}

.slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    cursor: pointer;
    box-shadow: 0 2px 8px rgba(102, 126, 234, 0.4);
    transition: all 0.2s ease;
}

.slider::-webkit-slider-thumb:hover {
    transform: scale(1.2);
    box-shadow: 0 4px 16px rgba(102, 126, 234, 0.6);
}

.slider::-moz-range-thumb {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    cursor: pointer;
    border: none;
    box-shadow: 0 2px 8px rgba(102, 126, 234, 0.4);
    transition: all 0.2s ease;
}

.slider::-moz-range-thumb:hover {
    transform: scale(1.2);
    box-shadow: 0 4px 16px rgba(102, 126, 234, 0.6);
}

/* Input Number */
.input-number {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-sm);
    padding: var(--spacing-xs) var(--spacing-sm);
    color: var(--text-primary);
    font-family: var(--font-body);
    font-size: 1rem;
    transition: all 0.3s ease;
}

.input-number:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.2);
}

/* Checkbox */
input[type="checkbox"] {
    width: 20px;
    height: 20px;
    accent-color: var(--primary);
    cursor: pointer;
}

/* ============================================
   BUTTONS
   ============================================ */
.btn {
    font-family: var(--font-body);
    font-size: 1rem;
    font-weight: 600;
    padding: var(--spacing-sm) var(--spacing-lg);
    border: none;
    border-radius: var(--border-radius-sm);
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    transition: all 0.3s ease;
    text-decoration: none;
}

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

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

.btn-primary:active {
    transform: translateY(0);
}

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

.btn-secondary:hover {
    background: var(--bg-card-hover);
    border-color: var(--primary);
}

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

.btn-success:hover {
    background: #22c55e;
}

/* ============================================
   RESULTS SECTION
   ============================================ */
.results-section {
    animation: fadeInUp 0.6s ease-out 0.4s both;
}

.results-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-md);
}

.results-header h3 {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    color: var(--text-primary);
}

.results-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: var(--spacing-md);
}

.result-card {
    background: var(--bg-card);
    backdrop-filter: blur(20px);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: var(--spacing-md);
    transition: all 0.3s ease;
    animation: fadeInUp 0.4s ease-out both;
}

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

.result-preview {
    width: 100%;
    aspect-ratio: 16/9;
    object-fit: cover;
    border-radius: var(--border-radius-sm);
    margin-bottom: var(--spacing-sm);
}

.result-info {
    margin-bottom: var(--spacing-sm);
}

.result-filename {
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
    word-break: break-word;
}

.result-stats {
    display: flex;
    justify-content: space-between;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-xs);
}

.stat {
    display: flex;
    flex-direction: column;
    font-size: 0.875rem;
}

.stat-label {
    color: var(--text-muted);
    font-size: 0.75rem;
}

.stat-value {
    color: var(--text-primary);
    font-weight: 600;
}

.result-savings {
    display: inline-block;
    background: rgba(74, 222, 128, 0.2);
    color: var(--success);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--border-radius-sm);
    font-size: 0.875rem;
    font-weight: 600;
}

.result-actions {
    display: flex;
    gap: var(--spacing-xs);
    margin-top: var(--spacing-sm);
}

.result-actions .btn {
    flex: 1;
    justify-content: center;
    font-size: 0.875rem;
    padding: var(--spacing-xs) var(--spacing-sm);
}

/* Progress Bar */
.progress-bar {
    width: 100%;
    height: 4px;
    background: var(--bg-secondary);
    border-radius: 2px;
    overflow: hidden;
    margin-top: var(--spacing-sm);
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--primary), var(--secondary));
    transition: width 0.3s ease;
    border-radius: 2px;
}

/* ============================================
   FOOTER
   ============================================ */
.footer {
    text-align: center;
    padding: var(--spacing-lg) 0;
    margin-top: var(--spacing-xl);
    border-top: 1px solid var(--border-color);
    color: var(--text-secondary);
}

.footer strong {
    color: var(--success);
}

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

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes float {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-10px);
    }
}

/* ============================================
   RESPONSIVE
   ============================================ */
@media (max-width: 768px) {
    .container {
        padding: var(--spacing-md) var(--spacing-sm);
    }
    
    .logo {
        font-size: 2rem;
    }
    
    .tagline {
        font-size: 1rem;
    }
    
    .dropzone {
        padding: var(--spacing-lg);
    }
    
    .dropzone h2 {
        font-size: 1.25rem;
    }
    
    .results-grid {
        grid-template-columns: 1fr;
    }
    
    .results-header {
        flex-direction: column;
        gap: var(--spacing-sm);
        align-items: stretch;
    }
    
    .results-header .btn {
        width: 100%;
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .logo {
        font-size: 1.5rem;
    }
    
    .upload-icon {
        width: 48px;
        height: 48px;
    }
    
    .result-stats {
        flex-direction: column;
        gap: var(--spacing-xs);
    }
}

/* ============================================
   UTILITY CLASSES
   ============================================ */
.hidden {
    display: none !important;
}

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

.mt-1 { margin-top: var(--spacing-xs); }
.mt-2 { margin-top: var(--spacing-sm); }
.mt-3 { margin-top: var(--spacing-md); }
.mt-4 { margin-top: var(--spacing-lg); }

.mb-1 { margin-bottom: var(--spacing-xs); }
.mb-2 { margin-bottom: var(--spacing-sm); }
.mb-3 { margin-bottom: var(--spacing-md); }
.mb-4 { margin-bottom: var(--spacing-lg); }