/**
 * styles.css — Main application design system
 * Premium dark mode with glassmorphism, gradients, and micro-animations.
 */

/* === Design Tokens === */
:root {
    --bg-primary: #0f0f1a;
    --bg-secondary: #1a1a2e;
    --bg-card: rgba(30, 30, 50, 0.8);
    --bg-glass: rgba(255, 255, 255, 0.04);
    --bg-glass-hover: rgba(255, 255, 255, 0.08);
    --border-glass: rgba(255, 255, 255, 0.08);
    --border-glass-hover: rgba(255, 255, 255, 0.15);

    --text-primary: #e8e8f0;
    --text-secondary: #9898b0;
    --text-muted: #6b6b85;

    --accent-primary: #6366f1;
    --accent-secondary: #8b5cf6;
    --accent-tertiary: #a78bfa;
    --accent-gradient: linear-gradient(135deg, #6366f1, #8b5cf6, #a78bfa);

    --success: #10b981;
    --success-bg: rgba(16, 185, 129, 0.1);
    --error: #ef4444;
    --error-bg: rgba(239, 68, 68, 0.1);
    --warning: #f59e0b;

    --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);
    --shadow-glow: 0 0 30px rgba(99, 102, 241, 0.15);

    --transition-fast: 150ms ease;
    --transition-normal: 250ms ease;
    --transition-slow: 400ms ease;
}

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

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
    overflow-x: hidden;
    line-height: 1.5;
}

.hidden {
    display: none !important;
}

/* === Background Gradient === */
.bg-gradient {
    position: fixed;
    inset: 0;
    z-index: -1;
    background:
        radial-gradient(ellipse 600px 400px at 20% 10%, rgba(99, 102, 241, 0.12), transparent),
        radial-gradient(ellipse 500px 300px at 80% 80%, rgba(139, 92, 246, 0.08), transparent),
        radial-gradient(ellipse 400px 400px at 50% 50%, rgba(167, 139, 250, 0.04), transparent);
    animation: gradientShift 20s ease-in-out infinite alternate;
}

@keyframes gradientShift {
    0% {
        opacity: 1;
    }

    50% {
        opacity: 0.7;
    }

    100% {
        opacity: 1;
    }
}

/* === App Container === */
.app-container {
    max-width: 900px;
    margin: 0 auto;
    padding: 24px 20px;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* === Header === */
.app-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 24px;
    padding: 16px 20px;
    background: var(--bg-glass);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-lg);
    backdrop-filter: blur(12px);
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo-icon {
    flex-shrink: 0;
}

.logo-text h1 {
    font-size: 1.25rem;
    font-weight: 700;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    line-height: 1.2;
}

.logo-subtitle {
    font-size: 0.75rem;
    color: var(--text-muted);
    font-weight: 400;
}

.header-badge {
    font-size: 0.7rem;
    font-weight: 600;
    padding: 4px 10px;
    border-radius: 20px;
    background: rgba(99, 102, 241, 0.15);
    color: var(--accent-tertiary);
    border: 1px solid rgba(99, 102, 241, 0.2);
    letter-spacing: 0.5px;
}

/* === Settings Panel === */
.settings-panel {
    margin-bottom: 24px;
}

.settings-content {
    transition: all var(--transition-normal);
}

/* === Status Bar === */
.status {
    min-height: 20px;
    padding: 0 4px;
    margin-bottom: 8px;
    font-size: 0.8rem;
    font-weight: 500;
    transition: all var(--transition-normal);
}

.status:empty {
    margin-bottom: 0;
}

.status-success {
    color: var(--success);
}

.status-error {
    color: var(--error);
}

.status-loading {
    color: var(--accent-tertiary);
    animation: pulse 1.5s ease-in-out infinite;
}

@keyframes pulse {

    0%,
    100% {
        opacity: 1;
    }

    50% {
        opacity: 0.5;
    }
}

/* === Drop Zone === */
.drop-zone {
    border: 2px dashed var(--border-glass-hover);
    border-radius: var(--radius-xl);
    padding: 60px 40px;
    text-align: center;
    cursor: pointer;
    transition: all var(--transition-normal);
    background: var(--bg-glass);
    backdrop-filter: blur(8px);
    position: relative;
    overflow: hidden;
}

.drop-zone::before {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--accent-gradient);
    opacity: 0;
    transition: opacity var(--transition-normal);
    border-radius: var(--radius-xl);
}

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

.drop-zone.drag-over::before {
    opacity: 0.05;
}

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

.drop-icon {
    color: var(--text-muted);
    margin-bottom: 20px;
    transition: color var(--transition-normal);
}

.drop-zone:hover .drop-icon,
.drop-zone.drag-over .drop-icon {
    color: var(--accent-tertiary);
}

.drop-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 6px;
}

.drop-subtitle {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-bottom: 24px;
}

.drop-formats {
    display: flex;
    gap: 8px;
    justify-content: center;
    margin-top: 24px;
}

.format-tag {
    font-size: 0.68rem;
    font-weight: 500;
    padding: 3px 10px;
    border-radius: 12px;
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-muted);
    border: 1px solid var(--border-glass);
}

/* === Buttons === */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 20px;
    font-family: inherit;
    font-size: 0.85rem;
    font-weight: 600;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
    text-decoration: none;
    line-height: 1;
}

.btn:active {
    transform: scale(0.97);
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.btn-primary {
    background: var(--accent-gradient);
    color: white;
    box-shadow: 0 2px 12px rgba(99, 102, 241, 0.3);
}

.btn-primary:hover:not(:disabled) {
    box-shadow: 0 4px 20px rgba(99, 102, 241, 0.5);
    transform: translateY(-1px);
}

.btn-success {
    background: linear-gradient(135deg, #059669, #10b981);
    color: white;
    box-shadow: 0 2px 12px rgba(16, 185, 129, 0.3);
}

.btn-success:hover:not(:disabled) {
    box-shadow: 0 4px 20px rgba(16, 185, 129, 0.5);
    transform: translateY(-1px);
}

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

.btn-ghost:hover:not(:disabled) {
    background: var(--bg-glass-hover);
    border-color: var(--border-glass-hover);
    color: var(--text-primary);
}

.btn-upload {
    background: var(--accent-gradient);
    color: white;
    padding: 14px 32px;
    font-size: 0.95rem;
    font-weight: 700;
    border-radius: var(--radius-lg);
    box-shadow: 0 4px 20px rgba(99, 102, 241, 0.35);
    letter-spacing: 0.3px;
    position: relative;
    overflow: hidden;
}

.btn-upload::before {
    content: '';
    position: absolute;
    inset: -2px;
    background: var(--accent-gradient);
    border-radius: inherit;
    z-index: -1;
    opacity: 0;
    filter: blur(12px);
    transition: opacity var(--transition-normal);
}

.btn-upload:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(99, 102, 241, 0.5);
}

.btn-upload:hover:not(:disabled)::before {
    opacity: 0.6;
}

/* === Preview Area === */
.preview {
    animation: fadeIn var(--transition-slow) ease;
    flex: 1;
}

.preview.visible {
    display: block;
}

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

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

.preview-toolbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 16px;
    margin-bottom: 16px;
    background: var(--bg-glass);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-md);
    backdrop-filter: blur(8px);
    flex-wrap: wrap;
    gap: 12px;
}

.preview-filename {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.82rem;
    color: var(--text-secondary);
}

.preview-filename svg {
    color: var(--accent-tertiary);
    flex-shrink: 0;
}

.preview-actions {
    display: flex;
    gap: 8px;
}

/* === Preview Paper (A4 simulation) === */
.preview-paper {
    background: white;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    overflow: hidden;
    min-height: 400px;
}

#preview-content {
    padding: 30px;
}

/* === Footer === */
.app-footer {
    margin-top: 24px;
    padding: 16px 20px;
    background: var(--bg-glass);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-md);
    backdrop-filter: blur(8px);
    text-align: center;
}

.footer-api-info {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    flex-wrap: wrap;
}

.footer-label {
    font-size: 0.72rem;
    color: var(--text-muted);
    font-weight: 500;
}

.footer-api-info code {
    font-size: 0.68rem;
    padding: 3px 8px;
    border-radius: 6px;
    background: rgba(99, 102, 241, 0.1);
    color: var(--accent-tertiary);
    font-family: 'JetBrains Mono', 'Fira Code', monospace;
}

/* === UPO Upload Section === */
.upo-upload-section {
    margin-bottom: 12px;
    padding: 10px 16px;
    background: rgba(99, 102, 241, 0.08);
    border: 1px dashed rgba(99, 102, 241, 0.25);
    border-radius: var(--radius-md);
    backdrop-filter: blur(8px);
}

.upo-upload-content {
    display: flex;
    align-items: center;
    gap: 16px;
    flex-wrap: wrap;
}

.upo-checkbox-label {
    display: flex;
    align-items: center;
    gap: 8px;
    cursor: pointer;
    font-size: 0.85rem;
    color: var(--text-primary);
    font-weight: 500;
    user-select: none;
}

.upo-checkbox-label input[type="checkbox"] {
    width: 16px;
    height: 16px;
    accent-color: var(--accent-primary);
    cursor: pointer;
}

.upo-file-area {
    display: flex;
    align-items: center;
    gap: 10px;
    animation: fadeIn 0.3s ease;
}

.btn-upo {
    background: rgba(99, 102, 241, 0.15);
    color: var(--accent-tertiary);
    border: 1px solid rgba(99, 102, 241, 0.3);
    padding: 5px 12px;
    font-size: 0.78rem;
}

.btn-upo:hover:not(:disabled) {
    background: rgba(99, 102, 241, 0.25);
    border-color: var(--accent-primary);
}

.upo-status-text {
    font-size: 0.72rem;
    color: var(--text-muted);
}

.upo-status-ok {
    color: var(--success) !important;
    font-weight: 600;
}

/* === Responsive === */
@media (max-width: 640px) {
    .app-container {
        padding: 16px 12px;
    }

    .app-header {
        padding: 12px 14px;
    }

    .drop-zone {
        padding: 40px 20px;
    }

    .drop-title {
        font-size: 1.1rem;
    }

    .preview-toolbar {
        flex-direction: column;
        align-items: stretch;
    }

    .preview-actions {
        justify-content: stretch;
    }

    .preview-actions .btn {
        flex: 1;
        justify-content: center;
    }

    #preview-content {
        padding: 16px;
    }

    .footer-api-info {
        flex-direction: column;
        gap: 6px;
    }

    .usage-counter {
        font-size: 0.7rem;
    }

    .upo-upload-content {
        flex-direction: column;
        align-items: stretch;
        text-align: center;
    }
}

/* === Usage Counter === */
.usage-counter {
    font-size: 0.75rem;
    color: var(--text-muted, #6b7280);
    text-align: center;
    margin-bottom: 6px;
    opacity: 0;
    transition: opacity 0.5s ease;
}

.usage-counter.visible {
    opacity: 1;
}