/* Reset and Base */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Colors - warm and earthy palette */
    --bg-primary: #F7F4EF;
    --bg-secondary: #FBF9F5;
    --bg-elevated: #FFFFFF;
    --border-subtle: #E7E1D7;
    --text-primary: #1F2421;
    --text-muted: #5C635D;
    --accent: #C4612F;
    --accent-hover: #A94E22;
    --accent-tint: #F2E3D6;
    --charcoal: #1F2421;
    
    /* Typography */
    --font-display: 'Playfair Display', serif;
    --font-body: 'Inter', sans-serif;
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 0.75rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(31, 36, 33, 0.05);
    --shadow-md: 0 2px 8px rgba(31, 36, 33, 0.08);
    --shadow-lg: 0 4px 16px rgba(31, 36, 33, 0.12);
    
    /* Radius */
    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-pill: 999px;
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;
}

body {
    font-family: var(--font-body);
    font-weight: 300;
    color: var(--text-primary);
    background: var(--bg-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Navigation */
.nav {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(251, 249, 245, 0.85);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border-subtle);
}

.nav-content {
    max-width: 1600px;
    margin: 0 auto;
    padding: var(--spacing-md) var(--spacing-xl);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.logo-icon {
    font-size: 1.5rem;
    color: var(--accent);
}

.logo-text {
    font-family: var(--font-display);
    font-size: 1.125rem;
    font-weight: 400;
    letter-spacing: -0.02em;
}

.nav-actions {
    display: flex;
    gap: var(--spacing-sm);
}

/* Layout */
.container {
    max-width: 1600px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 280px 1fr;
    gap: var(--spacing-xl);
    padding: var(--spacing-xl);
    min-height: calc(100vh - 80px);
}

/* Sidebar */
.sidebar {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

.btn-new-project {
    width: 100%;
    justify-content: center;
}

.sidebar-section {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.sidebar-heading {
    font-family: var(--font-body);
    font-size: 0.75rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted);
    padding: 0 var(--spacing-sm);
}

.project-list,
.batch-list {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.project-item,
.batch-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: background var(--transition-fast);
    font-size: 0.9375rem;
    font-weight: 400;
}

.project-item:hover,
.batch-item:hover {
    background: var(--bg-secondary);
}

.project-item.active,
.batch-item.active {
    background: var(--accent-tint);
    color: var(--accent);
    font-weight: 500;
}

.project-icon,
.batch-icon {
    font-size: 1.125rem;
}

/* Main Content */
.main-content {
    background: var(--bg-elevated);
    border-radius: var(--radius-lg);
    padding: var(--spacing-2xl);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-subtle);
}

/* Empty State */
.empty-state {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 500px;
}

.empty-state-content {
    max-width: 600px;
    text-align: center;
}

.empty-icon {
    font-size: 4rem;
    margin-bottom: var(--spacing-lg);
    color: var(--accent);
}

.empty-icon i {
    font-size: 4rem;
}

.empty-title {
    font-family: var(--font-display);
    font-size: 2.5rem;
    font-weight: 400;
    line-height: 1.2;
    letter-spacing: -0.03em;
    margin-bottom: var(--spacing-md);
}

.empty-title em {
    font-style: italic;
    color: var(--accent);
}

.empty-description {
    font-size: 1.0625rem;
    font-weight: 300;
    color: var(--text-muted);
    margin-bottom: var(--spacing-xl);
    line-height: 1.7;
}

/* Upload Zone */
.upload-zone {
    margin-top: var(--spacing-2xl);
    border: 2px dashed var(--border-subtle);
    border-radius: var(--radius-lg);
    padding: var(--spacing-2xl);
    cursor: pointer;
    transition: all var(--transition-base);
    background: var(--bg-secondary);
}

.upload-zone:hover {
    border-color: var(--accent);
    background: var(--accent-tint);
    transform: translateY(-2px);
}

.upload-zone.dragover {
    border-color: var(--accent);
    background: var(--accent-tint);
    border-style: solid;
}

.upload-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-sm);
}

.upload-icon {
    font-size: 2.5rem;
    margin-bottom: var(--spacing-sm);
    color: var(--text-muted);
    transition: color var(--transition-fast);
}

.upload-icon i {
    font-size: 2.5rem;
}

.upload-zone:hover .upload-icon {
    color: var(--accent);
}

.upload-text {
    font-size: 1.0625rem;
    font-weight: 400;
    color: var(--text-primary);
}

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

/* Project View */
.project-view {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xl);
}

.project-view.hidden {
    display: none;
}

.project-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-bottom: var(--spacing-lg);
    border-bottom: 1px solid var(--border-subtle);
}

.project-title {
    font-family: var(--font-display);
    font-size: 1.75rem;
    font-weight: 400;
    letter-spacing: -0.02em;
    border: none;
    background: transparent;
    color: var(--text-primary);
    padding: var(--spacing-xs) 0;
    width: 100%;
    max-width: 600px;
}

.project-title:focus {
    outline: none;
    border-bottom: 2px solid var(--accent);
}

.project-actions {
    display: flex;
    gap: var(--spacing-sm);
}

/* Analysis Status */
.analysis-status {
    margin-bottom: var(--spacing-lg);
}

.status-card {
    background: var(--accent-tint);
    border: 1px solid var(--accent);
    border-radius: var(--radius-md);
    padding: var(--spacing-lg);
}

.status-header {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
}

.status-icon {
    font-size: 1.5rem;
    color: var(--accent);
}

.status-title {
    font-size: 1.0625rem;
    font-weight: 500;
    color: var(--text-primary);
}

.progress-bar {
    height: 6px;
    background: var(--bg-elevated);
    border-radius: var(--radius-pill);
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: var(--accent);
    border-radius: var(--radius-pill);
    transition: width var(--transition-base);
    width: 0%;
}

/* Recommendation Card */
.recommendation-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    padding: var(--spacing-lg);
    position: relative;
}

.recommendation-badge {
    display: inline-block;
    background: var(--accent-tint);
    color: var(--accent);
    font-size: 0.75rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    padding: var(--spacing-xs) var(--spacing-md);
    border-radius: var(--radius-pill);
    margin-bottom: var(--spacing-sm);
}

.recommendation-title {
    font-family: var(--font-display);
    font-size: 1.375rem;
    font-weight: 400;
    margin-bottom: var(--spacing-xs);
    letter-spacing: -0.01em;
}

.recommendation-desc {
    font-size: 0.9375rem;
    color: var(--text-muted);
    font-weight: 300;
}

/* AB Player */
.ab-player {
    background: var(--bg-secondary);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    padding: var(--spacing-lg);
}

.player-tabs {
    display: flex;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-lg);
    background: var(--bg-elevated);
    padding: 4px;
    border-radius: var(--radius-pill);
    width: fit-content;
}

.player-tab {
    padding: var(--spacing-sm) var(--spacing-lg);
    border: none;
    background: transparent;
    color: var(--text-muted);
    font-family: var(--font-body);
    font-size: 0.9375rem;
    font-weight: 400;
    border-radius: var(--radius-pill);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.player-tab:hover {
    color: var(--text-primary);
}

.player-tab.active {
    background: var(--accent);
    color: var(--bg-elevated);
    font-weight: 500;
}

.waveform-container {
    position: relative;
    height: 120px;
    background: var(--bg-elevated);
    border-radius: var(--radius-sm);
    margin-bottom: var(--spacing-lg);
    overflow: hidden;
}

.waveform {
    width: 100%;
    height: 100%;
}

.playhead {
    position: absolute;
    top: 0;
    left: 0;
    width: 2px;
    height: 100%;
    background: var(--accent);
    pointer-events: none;
    transition: left 100ms linear;
}

.player-controls {
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
}

.btn-play {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    border: none;
    background: var(--accent);
    color: var(--bg-elevated);
    font-size: 1.125rem;
    cursor: pointer;
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.btn-play:hover {
    background: var(--accent-hover);
    transform: translateY(-1px);
}

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

.btn-play i {
    font-size: 1.25rem;
}

.time-display {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: 0.9375rem;
    font-weight: 400;
    color: var(--text-muted);
    font-variant-numeric: tabular-nums;
}

.time-separator {
    color: var(--border-subtle);
}

.volume-slider {
    flex: 1;
    max-width: 120px;
}

.volume-icon {
    font-size: 1.25rem;
    color: var(--text-muted);
    margin-left: var(--spacing-sm);
}

/* Reconstruction Controls */
.reconstruction-controls {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

.control-group {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.control-label {
    font-size: 0.9375rem;
    font-weight: 500;
    color: var(--text-primary);
}

.slider-container {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.slider-label {
    font-size: 0.875rem;
    color: var(--text-muted);
    white-space: nowrap;
    font-weight: 300;
}

.reconstruction-slider {
    flex: 1;
}

.slider-value {
    text-align: center;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--accent);
    font-variant-numeric: tabular-nums;
}

/* Range Inputs */
input[type="range"] {
    -webkit-appearance: none;
    appearance: none;
    width: 100%;
    height: 6px;
    border-radius: var(--radius-pill);
    background: var(--border-subtle);
    outline: none;
    cursor: pointer;
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--accent);
    cursor: pointer;
    transition: all var(--transition-fast);
}

input[type="range"]::-moz-range-thumb {
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--accent);
    cursor: pointer;
    border: none;
    transition: all var(--transition-fast);
}

input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.2);
    box-shadow: 0 0 0 8px rgba(196, 97, 47, 0.1);
}

input[type="range"]::-moz-range-thumb:hover {
    transform: scale(1.2);
    box-shadow: 0 0 0 8px rgba(196, 97, 47, 0.1);
}

/* Buttons */
.btn-primary,
.btn-secondary,
.btn-icon {
    font-family: var(--font-body);
    font-size: 0.9375rem;
    font-weight: 400;
    padding: var(--spacing-sm) var(--spacing-lg);
    border: none;
    border-radius: var(--radius-pill);
    cursor: pointer;
    transition: all var(--transition-fast);
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.btn-primary i,
.btn-secondary i,
.btn-icon i {
    font-size: 1.125rem;
}

.btn-primary {
    background: var(--accent);
    color: var(--bg-elevated);
    font-weight: 500;
}

.btn-primary:hover {
    background: var(--accent-hover);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

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

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

.btn-secondary:hover {
    background: var(--bg-elevated);
    transform: translateY(-1px);
}

.btn-icon {
    width: 36px;
    height: 36px;
    padding: 0;
    justify-content: center;
    background: var(--bg-secondary);
    border: 1px solid var(--border-subtle);
}

.btn-icon:hover {
    background: var(--bg-elevated);
    transform: translateY(-1px);
}

.btn-generate {
    align-self: flex-start;
    padding: var(--spacing-md) var(--spacing-2xl);
    font-size: 1.0625rem;
}

/* Advanced Settings */
.advanced-settings {
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    overflow: hidden;
}

.advanced-toggle {
    padding: var(--spacing-md) var(--spacing-lg);
    cursor: pointer;
    background: var(--bg-secondary);
    font-size: 0.9375rem;
    font-weight: 500;
    color: var(--text-primary);
    user-select: none;
    transition: background var(--transition-fast);
    list-style: none;
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.advanced-toggle i {
    font-size: 1.125rem;
}

.advanced-toggle::-webkit-details-marker {
    display: none;
}

.advanced-toggle:hover {
    background: var(--bg-elevated);
}

.advanced-content {
    padding: var(--spacing-lg);
    background: var(--bg-elevated);
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: var(--spacing-lg);
}

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

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

.form-select {
    padding: var(--spacing-sm) var(--spacing-md);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-sm);
    background: var(--bg-secondary);
    color: var(--text-primary);
    font-family: var(--font-body);
    font-size: 0.9375rem;
    font-weight: 400;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.form-select:hover {
    border-color: var(--accent);
}

.form-select:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(196, 97, 47, 0.1);
}

/* Generation Progress */
.generation-progress {
    background: var(--bg-secondary);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    padding: var(--spacing-lg);
}

.progress-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.progress-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md);
    border-radius: var(--radius-sm);
    background: var(--bg-elevated);
    font-size: 0.9375rem;
}

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

.progress-item.completed .progress-icon {
    color: var(--accent);
}

.progress-item.active {
    background: var(--accent-tint);
    color: var(--accent);
    font-weight: 500;
}

.progress-icon {
    font-size: 1.25rem;
    width: 24px;
    text-align: center;
}

.progress-item.active .progress-icon.spinning {
    animation: spin 1s linear infinite;
}

@keyframes spin {
    from {
        transform: rotate(0deg);
    }
    to {
        transform: rotate(360deg);
    }
}

.progress-name {
    flex: 1;
}

.progress-percent {
    font-size: 0.875rem;
    font-weight: 500;
    font-variant-numeric: tabular-nums;
}

/* Generation History */
.generation-history {
    border-top: 1px solid var(--border-subtle);
    padding-top: var(--spacing-lg);
}

.history-heading {
    font-family: var(--font-body);
    font-size: 1.0625rem;
    font-weight: 500;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

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

.history-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-md);
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-subtle);
    cursor: pointer;
    transition: all var(--transition-fast);
    background: var(--bg-secondary);
}

.history-item:hover {
    background: var(--bg-elevated);
    transform: translateY(-1px);
    box-shadow: var(--shadow-sm);
}

.history-item.active {
    border-color: var(--accent);
    background: var(--accent-tint);
}

.history-info {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.history-version {
    font-weight: 500;
    color: var(--text-primary);
    font-size: 0.9375rem;
}

.history-label {
    font-size: 0.875rem;
    color: var(--text-muted);
    font-weight: 300;
}

.history-time {
    font-size: 0.8125rem;
    color: var(--text-muted);
    font-variant-numeric: tabular-nums;
}

/* Utility Classes */
.hidden {
    display: none !important;
}

/* Responsive */
@media (max-width: 1024px) {
    .container {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }
    
    .sidebar {
        display: none;
    }
}

@media (max-width: 640px) {
    .container {
        padding: var(--spacing-md);
    }
    
    .main-content {
        padding: var(--spacing-lg);
    }
    
    .empty-title {
        font-size: 2rem;
    }
    
    .advanced-content {
        grid-template-columns: 1fr;
    }
}