/* CSS Variables */
:root {
    --primary-color: #6366f1;
    --primary-hover: #4f46e5;
    --primary-light: #e0e7ff;
    --secondary-color: #64748b;
    --success-color: #10b981;
    --danger-color: #ef4444;
    --warning-color: #f59e0b;
    --background-color: #f8fafc;
    --surface-color: #ffffff;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --border-color: #e2e8f0;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --transition: all 0.2s ease;
}

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

/* Base Styles */
html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background-color: var(--background-color);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
}

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

/* Header */
header {
    text-align: center;
    padding: 2rem 1rem;
    background: linear-gradient(135deg, var(--primary-color), #8b5cf6);
    color: white;
}

.logo-container {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    margin-bottom: 0.5rem;
}

.logo {
    width: 48px;
    height: 48px;
    object-fit: contain;
}

header h1 {
    font-size: 1.75rem;
    font-weight: 700;
    letter-spacing: -0.025em;
}

.tagline {
    font-size: 1rem;
    opacity: 0.9;
    margin-top: 0.25rem;
}

/* Main Content */
main {
    flex: 1;
    max-width: 900px;
    margin: 0 auto;
    padding: 1.5rem 1rem;
    width: 100%;
}

/* Sections */
.section {
    background: var(--surface-color);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    box-shadow: var(--shadow-md);
}

.section h2 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.hidden {
    display: none !important;
}

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

.upload-area:hover,
.upload-area.drag-over {
    border-color: var(--primary-color);
    background: var(--primary-light);
}

.upload-icon {
    color: var(--secondary-color);
    margin-bottom: 1rem;
}

.upload-area:hover .upload-icon,
.upload-area.drag-over .upload-icon {
    color: var(--primary-color);
}

.upload-text {
    font-size: 1.125rem;
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.upload-subtext {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

/* File Info */
.file-info {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.75rem 1rem;
    background: var(--primary-light);
    border-radius: var(--radius-md);
    margin-top: 1rem;
}

.file-info span {
    font-size: 0.875rem;
    color: var(--primary-color);
    font-weight: 500;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.625rem 1.25rem;
    font-size: 0.9375rem;
    font-weight: 500;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition);
}

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

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

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

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

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

.btn-danger:hover {
    background: #dc2626;
}

.btn-large {
    padding: 1rem 2rem;
    font-size: 1.0625rem;
    width: 100%;
}

.btn-icon {
    background: transparent;
    border: none;
    padding: 0.5rem;
    cursor: pointer;
    color: var(--text-secondary);
    border-radius: var(--radius-sm);
    transition: var(--transition);
}

.btn-icon:hover {
    background: var(--background-color);
    color: var(--danger-color);
}

.btn-sm {
    padding: 0.5rem 0.875rem;
    font-size: 0.8125rem;
}

/* Video Container */
.video-container {
    background: #000;
    border-radius: var(--radius-md);
    overflow: hidden;
    aspect-ratio: 16/9;
}

.video-container video {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.video-info {
    margin-top: 0.75rem;
    font-size: 0.875rem;
    color: var(--text-secondary);
}

/* Segments */
.segments-controls {
    margin-bottom: 1rem;
}

.segments-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.segment-item {
    background: var(--background-color);
    border-radius: var(--radius-md);
    padding: 1rem;
    border: 1px solid var(--border-color);
}

.segment-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 0.75rem;
}

.segment-title {
    font-weight: 600;
    font-size: 0.9375rem;
}

.segment-controls {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
}

.segment-control {
    display: flex;
    flex-direction: column;
    gap: 0.375rem;
}

.segment-control label {
    font-size: 0.8125rem;
    color: var(--text-secondary);
}

.segment-control input {
    padding: 0.5rem 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-size: 0.875rem;
    transition: var(--transition);
}

.segment-control input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px var(--primary-light);
}

.segment-preview-btn {
    margin-top: 0.75rem;
}

.segment-duration {
    font-size: 0.8125rem;
    color: var(--text-secondary);
    margin-top: 0.5rem;
}

/* Settings */
.settings-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
}

.setting-item {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.setting-item label {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-primary);
}

.setting-item select {
    padding: 0.625rem 0.875rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-size: 0.875rem;
    background: var(--surface-color);
    cursor: pointer;
    transition: var(--transition);
}

.setting-item select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px var(--primary-light);
}

/* Progress */
.progress-container {
    margin-top: 1.5rem;
}

.progress-bar {
    height: 8px;
    background: var(--background-color);
    border-radius: 4px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--primary-color), #8b5cf6);
    width: 0%;
    transition: width 0.3s ease;
}

.progress-text {
    text-align: center;
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-top: 0.75rem;
}

/* Results */
.results-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.result-item {
    background: var(--background-color);
    border-radius: var(--radius-md);
    overflow: hidden;
    border: 1px solid var(--border-color);
}

.result-preview {
    aspect-ratio: 16/9;
    background: #000;
    display: flex;
    align-items: center;
    justify-content: center;
}

.result-preview img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
}

.result-info {
    padding: 0.75rem;
}

.result-name {
    font-size: 0.875rem;
    font-weight: 500;
    margin-bottom: 0.25rem;
}

.result-size {
    font-size: 0.75rem;
    color: var(--text-secondary);
    margin-bottom: 0.75rem;
}

.result-actions {
    display: flex;
    gap: 0.5rem;
}

.result-actions .btn {
    flex: 1;
}

/* Footer */
footer {
    text-align: center;
    padding: 1.5rem 1rem;
    background: var(--surface-color);
    border-top: 1px solid var(--border-color);
    margin-top: auto;
}

footer p {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

footer a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
}

footer a:hover {
    color: var(--primary-hover);
    text-decoration: underline;
}

/* Mobile Responsive */
@media (max-width: 640px) {
    header {
        padding: 1.5rem 1rem;
    }

    header h1 {
        font-size: 1.5rem;
    }

    .logo {
        width: 40px;
        height: 40px;
    }

    .tagline {
        font-size: 0.875rem;
    }

    main {
        padding: 1rem;
    }

    .section {
        padding: 1rem;
        margin-bottom: 1rem;
    }

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

    .upload-icon svg {
        width: 48px;
        height: 48px;
    }

    .segment-controls {
        grid-template-columns: 1fr;
    }

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

    .results-list {
        grid-template-columns: 1fr;
    }

    .btn-large {
        padding: 0.875rem 1.5rem;
        font-size: 1rem;
    }
}

/* Animation */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.section:not(.hidden) {
    animation: fadeIn 0.3s ease;
}

/* Loading spinner */
.spinner {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 0.8s linear infinite;
}

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

/* Disabled state */
.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

/* Toast notifications */
.toast {
    position: fixed;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    background: var(--text-primary);
    color: white;
    padding: 0.875rem 1.5rem;
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    z-index: 1000;
    animation: slideUp 0.3s ease;
    box-shadow: var(--shadow-lg);
}

.toast.error {
    background: var(--danger-color);
}

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

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateX(-50%) translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateX(-50%) translateY(0);
    }
}

/* Range input for time selection */
.time-range-container {
    margin-top: 0.75rem;
}

.time-range {
    width: 100%;
    height: 6px;
    -webkit-appearance: none;
    appearance: none;
    background: var(--border-color);
    border-radius: 3px;
    outline: none;
}

.time-range::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 16px;
    height: 16px;
    background: var(--primary-color);
    border-radius: 50%;
    cursor: pointer;
    transition: var(--transition);
}

.time-range::-webkit-slider-thumb:hover {
    transform: scale(1.1);
}

.time-range::-moz-range-thumb {
    width: 16px;
    height: 16px;
    background: var(--primary-color);
    border: none;
    border-radius: 50%;
    cursor: pointer;
}