/* ========================================
   CSS CUSTOM PROPERTIES (DESIGN TOKENS)
   ======================================== */
:root {
    /* Color palette */
    --primary-bg: #242424;
    --secondary-bg: #1c1c1c;
    --accent-bg: #171717;
    --darker-bg: #2c2c2c;
    --primary-color: #fff;
    --accent-color: #8d37bf;
    --border-color: #7c35a6;
    
    /* Visual effects */
    --shadow: 0 0 16px rgba(0, 0, 0, 1);
    --border-radius: 8px;
    
    /* Animation & transitions */
    --transition: all 0.3s ease;
    
    /* Performance optimizations */
    --will-change-transform: transform;
    --will-change-opacity: opacity;
    
    /* Accessibility */
    --focus-ring: 2px solid var(--accent-color);
    --focus-offset: 2px;
}

/* Respect user motion preferences */
@media (prefers-reduced-motion: reduce) {
    :root {
        --transition: none;
    }
    
    html {
        scroll-behavior: auto;
    }
    
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* Modern CSS Reset */
*,
*::before,
*::after {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    padding: 0;
    background-color: var(--primary-bg);
    font-family: 'Montserrat', sans-serif;
    line-height: 1.6;
    color: var(--primary-color);
}

/* Modern scrollbar styling */
::-webkit-scrollbar {
    width: 12px;
}

::-webkit-scrollbar-thumb {
    background: linear-gradient(180deg, #6b247d, #8d37bf);
    border-radius: 6px;
    box-shadow: inset 0 1px 2px rgba(0, 0, 0, 0.2);
}

::-webkit-scrollbar-track {
    background: var(--darker-bg);
    border-radius: 6px;
    box-shadow: inset 0 1px 2px rgba(0, 0, 0, 0.1);
}

/* Layout improvements */
.container {
    width: min(90%, 1200px);
    margin: 0 auto;
    padding: 0 1rem;
}

/* Navigation active state */
.active {
    background-color: var(--accent-bg);
    border-radius: var(--border-radius);
}

/* Header section */
.header {
    background: linear-gradient(rgba(0, 0, 0, 0.4), rgba(0, 0, 0, 0.4)),
                url(banner.jpeg) no-repeat center center;
    background-size: cover;
    background-attachment: scroll;
    text-align: center;
    border-bottom: 5px solid var(--border-color);
    min-height: 300px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.logo-wrapper {
    padding: 2rem;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* Panel styling - Updated for Bootstrap 5 Cards */
.card {
    border: 2px solid var(--secondary-bg);
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    background-color: transparent;
}

.card-header {
    background-color: var(--secondary-bg);
    color: var(--primary-color);
    padding: 1rem;
    border-bottom: 1px solid var(--accent-bg);
    font-size: 1.2rem;
    font-weight: 600;
}

.card-body {
    background-color: var(--primary-bg);
    color: var(--primary-color);
    padding: 2rem;
}

.card-footer {
    background-color: var(--secondary-bg);
    color: var(--primary-color);
    padding: 1rem;
    border-top: 1px solid var(--accent-bg);
}

/* Typography */
h1 {
    color: var(--primary-color);
    font-size: clamp(2rem, 5vw, 3.5rem);
    text-shadow: var(--shadow);
    margin: 0;
    font-weight: 700;
    background: rgba(0, 0, 0, 0.5);
    padding: 1rem;
    border-radius: var(--border-radius);
    backdrop-filter: blur(10px);
}

h3, h5 {
    color: var(--accent-color);
    font-size: clamp(1.25rem, 3vw, 1.75rem);
    text-shadow: var(--shadow);
    margin-bottom: 1rem;
}

h5 {
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
}

p {
    color: var(--primary-color);
    font-size: 1rem;
    text-shadow: var(--shadow);
    margin-bottom: 1rem;
}

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

a:hover,
a:focus {
    color: var(--accent-color);
    outline: 2px solid transparent;
}

/* Well component */
.well {
    border-radius: var(--border-radius);
    padding: 2rem;
    text-align: left;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    max-width: 900px;
    width: 100%;
    margin: 0 auto;
}

/* Decorative divider */
.ok {
    border: none;
    width: 60%;
    height: 3px;
    background: linear-gradient(
        to right,
        transparent,
        rgba(129, 51, 158, 0.75),
        transparent
    );
    margin: 1.5rem auto;
    border-radius: 2px;
}

/* Video2WebP specific styles */
.upload-section {
    margin-bottom: 20px;
}

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

.stats {
    background: linear-gradient(135deg, var(--accent-bg), var(--secondary-bg));
    padding: 1rem;
    border-radius: var(--border-radius);
    border: 1px solid var(--accent-color);
    color: var(--primary-color);
    font-weight: 500;
}

.controls-section {
    background-color: var(--accent-bg);
    padding: 1.5rem;
    border-radius: var(--border-radius);
    border: 1px solid var(--secondary-bg);
    margin-bottom: 1rem;
}

.output-section {
    text-align: center;
    padding: 1rem;
    background-color: var(--accent-bg);
    border-radius: var(--border-radius);
    border: 1px solid var(--secondary-bg);
}

/* Form styling */
.form-control, .form-select {
    background-color: var(--secondary-bg);
    border: 1px solid var(--accent-color);
    color: var(--primary-color);
    border-radius: var(--border-radius);
    transition: var(--transition);
}

.form-control:focus, .form-select:focus {
    background-color: var(--secondary-bg);
    border-color: var(--accent-color);
    box-shadow: 0 0 0 0.2rem rgba(141, 55, 191, 0.25);
    color: var(--primary-color);
    outline: none;
}

.form-control:focus-visible, .form-select:focus-visible {
    outline: var(--focus-ring);
    outline-offset: var(--focus-offset);
}

.form-control:invalid {
    border-color: #dc3545;
    box-shadow: 0 0 0 0.2rem rgba(220, 53, 69, 0.25);
}

.form-control:valid {
    border-color: #28a745;
}

.form-range {
    background: transparent;
}

.form-range::-webkit-slider-track {
    background: var(--secondary-bg);
    border: 1px solid var(--accent-color);
    border-radius: var(--border-radius);
    height: 8px;
}

.form-range::-webkit-slider-thumb {
    background: var(--accent-color);
    border: none;
    border-radius: 50%;
    width: 20px;
    height: 20px;
}

.form-range::-moz-range-track {
    background: var(--secondary-bg);
    border: 1px solid var(--accent-color);
    border-radius: var(--border-radius);
    height: 8px;
}

.form-range::-moz-range-thumb {
    background: var(--accent-color);
    border: none;
    border-radius: 50%;
    width: 20px;
    height: 20px;
}

/* Button styling */
.btn {
    border-radius: var(--border-radius);
    font-weight: 500;
    transition: var(--transition);
    will-change: var(--will-change-transform);
    cursor: pointer;
}

.btn:focus-visible {
    outline: var(--focus-ring);
    outline-offset: var(--focus-offset);
}

.btn-primary {
    background-color: var(--accent-color);
    border-color: var(--accent-color);
}

.btn-primary:hover {
    background-color: #6b247d;
    border-color: #6b247d;
}

.btn-success {
    background-color: #28a745;
    border-color: #28a745;
}

.btn-success:hover {
    background-color: #1e7e34;
    border-color: #1e7e34;
}

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

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

.btn-outline-primary {
    border-color: var(--accent-color);
    color: var(--accent-color);
}

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

.btn-outline-secondary {
    border-color: var(--secondary-bg);
    color: var(--primary-color);
}

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

/* Badge styling */
.badge {
    background-color: var(--accent-color) !important;
}

/* Form labels */
.form-label {
    color: var(--primary-color);
    font-weight: 500;
    margin-bottom: 0.5rem;
}

/* Video element */
video {
    border: 2px solid var(--accent-color);
    border-radius: var(--border-radius);
    background-color: var(--secondary-bg);
}

/* Image output */
#webpOutput {
    border: 2px solid var(--accent-color);
    border-radius: var(--border-radius);
    background-color: var(--secondary-bg);
    max-width: 100%;
    height: auto;
}

/* Enhanced responsive design with modern units */
@media (max-width: 768px) {
    .header {
        background-attachment: scroll;
        min-height: clamp(200px, 40vh, 250px);
    }
    
    .logo-wrapper {
        padding: 1rem;
    }
    
    .well {
        padding: 1.5rem;
    }
    
    .card-body {
        padding: 1rem;
    }
    
    .controls-section {
        padding: 1rem;
    }
}

/* Container queries for better responsive design */
@container (max-width: 500px) {
    .card-body {
        padding: 1rem;
    }
    
    .stats {
        font-size: 0.9rem;
    }
}

/* High contrast mode support */
@media (prefers-contrast: high) {
    :root {
        --shadow: 0 0 8px rgba(255, 255, 255, 0.8);
        --accent-color: #a855f7;
        --border-color: #9333ea;
    }
    
    .card {
        border-width: 3px;
    }
    
    .btn {
        border-width: 2px;
    }
}

/* Print styles */
@media print {
    :root {
        --shadow: none;
        --transition: none;
    }
    
    .header {
        background: none !important;
        color: black !important;
        text-shadow: none !important;
    }
    
    .btn, .form-control, .form-select {
        border: 1px solid black !important;
        background: white !important;
        color: black !important;
    }
}

/* Performance optimizations for transforms and animations */
.card, .btn, h1 {
    transform: translateZ(0);
    backface-visibility: hidden;
}

/* Modern logical properties for better internationalization */
.container {
    padding-inline: 1rem;
    margin-inline: auto;
}

.card-header, .card-body, .card-footer {
    padding-inline: 1rem;
}

.well {
    margin-inline: auto;
    text-align: start;
}

/* Focus styles for accessibility - Enhanced */
:focus-visible {
    outline: var(--focus-ring);
    outline-offset: var(--focus-offset);
}

/* Skip link for accessibility */
.skip-link {
    position: absolute;
    top: -40px;
    left: 6px;
    background: var(--accent-color);
    color: var(--primary-color);
    padding: 8px;
    text-decoration: none;
    border-radius: var(--border-radius);
    z-index: 1000;
    transition: var(--transition);
}

.skip-link:focus {
    top: 6px;
}

/* Reduced motion fallbacks for specific animations */
@media (prefers-reduced-motion: reduce) {
    .header {
        backdrop-filter: none;
    }
    
    h1 {
        backdrop-filter: none;
    }
}