/* ================================================================
   PDF Forge — Style System
   Design System: deeplek.com / SpriteForge
   ================================================================ */

/* ----------------------------------------------------------------
   1. CSS Custom Properties (Light Theme — Default)
   ---------------------------------------------------------------- */
:root {
    /* ── Brand Colors ── */
    --color-teal: #3BB4B4;
    --color-teal-light: #4ec9c9;
    --color-teal-dark: #2d9a9a;
    --color-orange-start: #E47911;
    --color-orange-end: #D2680D;
    --gradient-orange: linear-gradient(135deg, var(--color-orange-start), var(--color-orange-end));
    --gradient-teal: linear-gradient(135deg, #3BB4B4, #2d9a9a);

    /* ── Backgrounds ── */
    --bg-primary: #f8f9fa;
    --bg-surface: #ffffff;
    --bg-glass: rgba(255, 255, 255, 0.72);
    --bg-glass-hover: rgba(255, 255, 255, 0.88);
    --bg-subtle: rgba(0, 0, 0, 0.03);
    --bg-file-item: rgba(0, 0, 0, 0.02);
    --bg-file-item-hover: rgba(59, 180, 180, 0.06);
    --bg-input: #ffffff;
    --bg-progress-track: rgba(0, 0, 0, 0.06);
    --bg-privacy: rgba(59, 180, 180, 0.06);
    --bg-format-tag: rgba(59, 180, 180, 0.10);
    --bg-notification: #ffffff;

    /* ── Text ── */
    --text-primary: #333333;
    --text-secondary: #666666;
    --text-tertiary: #999999;
    --text-inverse: #ffffff;

    /* ── Borders ── */
    --border-light: rgba(0, 0, 0, 0.06);
    --border-medium: rgba(0, 0, 0, 0.10);
    --border-strong: rgba(0, 0, 0, 0.15);
    --border-dashed: rgba(0, 0, 0, 0.18);
    --border-input: rgba(0, 0, 0, 0.12);
    --border-input-focus: var(--color-teal);

    /* ── Shadows ── */
    --shadow-xs: 0 1px 2px rgba(0, 0, 0, 0.04);
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.06);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.10);
    --shadow-xl: 0 12px 48px rgba(0, 0, 0, 0.14);
    --shadow-teal-glow: 0 0 20px rgba(59, 180, 180, 0.25);
    --shadow-orange-glow: 0 0 24px rgba(228, 121, 17, 0.30);
    --shadow-teal-sm: 0 0 12px rgba(59, 180, 180, 0.15);

    /* ── Spacing ── */
    --space-xs: 4px;
    --space-sm: 8px;
    --space-md: 16px;
    --space-lg: 24px;
    --space-xl: 32px;
    --space-2xl: 48px;

    /* ── Radii ── */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 20px;
    --radius-full: 9999px;

    /* ── Typography ── */
    --font-sans: 'Poppins', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-heading: 'Roboto', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', 'Cascadia Code', monospace;

    /* ── Semantic Colors ── */
    --color-success: #34d399;
    --color-error: #f87171;
    --color-info: #60a5fa;
    --color-warning: #fbbf24;

    /* ── Transitions ── */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-normal: 250ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 400ms cubic-bezier(0.4, 0, 0.2, 1);

    /* ── Scrollbar ── */
    --scrollbar-thumb: rgba(0, 0, 0, 0.15);
    --scrollbar-track: transparent;
}

/* ----------------------------------------------------------------
   2. Dark Theme Overrides
   ---------------------------------------------------------------- */
body.dark-theme {
    --bg-primary: #121212;
    --bg-surface: #242424;
    --bg-glass: rgba(36, 36, 36, 0.75);
    --bg-glass-hover: rgba(36, 36, 36, 0.90);
    --bg-subtle: rgba(255, 255, 255, 0.04);
    --bg-file-item: rgba(255, 255, 255, 0.03);
    --bg-file-item-hover: rgba(59, 180, 180, 0.08);
    --bg-input: #1e1e1e;
    --bg-progress-track: rgba(255, 255, 255, 0.08);
    --bg-privacy: rgba(59, 180, 180, 0.08);
    --bg-format-tag: rgba(59, 180, 180, 0.14);
    --bg-notification: #2a2a2a;

    --text-primary: #f0f0f0;
    --text-secondary: #a0a0a0;
    --text-tertiary: #777777;

    --border-light: rgba(255, 255, 255, 0.06);
    --border-medium: rgba(255, 255, 255, 0.10);
    --border-strong: rgba(255, 255, 255, 0.15);
    --border-dashed: rgba(255, 255, 255, 0.18);
    --border-input: rgba(255, 255, 255, 0.12);

    --shadow-xs: 0 1px 2px rgba(0, 0, 0, 0.20);
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.25);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.30);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.35);
    --shadow-xl: 0 12px 48px rgba(0, 0, 0, 0.40);
    --shadow-teal-glow: 0 0 24px rgba(59, 180, 180, 0.30);
    --shadow-orange-glow: 0 0 28px rgba(228, 121, 17, 0.35);
    --shadow-teal-sm: 0 0 14px rgba(59, 180, 180, 0.20);

    --scrollbar-thumb: rgba(255, 255, 255, 0.15);
}

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

html {
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-rendering: optimizeLegibility;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    opacity: 0;
    transition: opacity var(--transition-slow), background-color var(--transition-normal), color var(--transition-normal);
}

body.loaded {
    opacity: 1;
}

a {
    color: var(--color-teal);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--color-teal-light);
    text-decoration: underline;
}

button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    outline: none;
    background: none;
}

input {
    font-family: inherit;
    outline: none;
}

img {
    max-width: 100%;
    display: block;
}

/* ── Scrollbar ── */
::-webkit-scrollbar {
    width: 6px;
    height: 6px;
}

::-webkit-scrollbar-track {
    background: var(--scrollbar-track);
}

::-webkit-scrollbar-thumb {
    background: var(--scrollbar-thumb);
    border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--color-teal);
}

/* Firefox */
* {
    scrollbar-width: thin;
    scrollbar-color: var(--scrollbar-thumb) var(--scrollbar-track);
}

/* ----------------------------------------------------------------
   4. Layout
   ---------------------------------------------------------------- */
.app-container {
    max-width: 960px;
    margin: 0 auto;
    padding: var(--space-lg);
    display: flex;
    flex-direction: column;
    gap: var(--space-lg);
}

/* ----------------------------------------------------------------
   5. Header
   ---------------------------------------------------------------- */
.app-header {
    position: relative;
    text-align: center;
    background: var(--bg-glass);
    backdrop-filter: blur(24px);
    -webkit-backdrop-filter: blur(24px);
    border: 1px solid var(--border-medium);
    border-radius: var(--radius-xl);
    padding: var(--space-xl) var(--space-lg);
    box-shadow: var(--shadow-sm);
    animation: fadeSlideUp 0.6s ease-out both;
}

.logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-md);
    margin-bottom: var(--space-sm);
}

.logo-icon {
    font-size: 42px;
    line-height: 1;
    background: var(--gradient-orange);
    -webkit-background-clip: text;
    background-clip: text;
    filter: drop-shadow(0 2px 6px rgba(228, 121, 17, 0.3));
    animation: logoPulse 3s ease-in-out infinite;
}

.logo-text {
    font-family: var(--font-heading);
    font-size: 32px;
    font-weight: 800;
    color: var(--color-teal);
    letter-spacing: -0.5px;
    line-height: 1.2;
}

.app-subtitle {
    font-size: 14px;
    color: var(--text-secondary);
    font-weight: 400;
    max-width: 560px;
    margin: 0 auto;
    line-height: 1.6;
}

.app-subtitle span {
    display: inline;
}

/* ── Theme Toggle ── */
.theme-toggle {
    position: absolute;
    top: var(--space-md);
    right: var(--space-md);
    width: 40px;
    height: 40px;
    border-radius: var(--radius-full);
    background: var(--bg-subtle);
    border: 1px solid var(--border-light);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    transition: all var(--transition-fast);
    z-index: 10;
}

.theme-toggle:hover {
    transform: scale(1.12);
    background: var(--bg-glass-hover);
    box-shadow: var(--shadow-md);
    border-color: var(--border-medium);
}

.theme-toggle:active {
    transform: scale(0.95);
}

/* ----------------------------------------------------------------
   6. Tool Selector
   ---------------------------------------------------------------- */
.tool-selector {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-md);
    animation: fadeSlideUp 0.6s ease-out 0.1s both;
}

.tool-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-sm);
    padding: var(--space-lg) var(--space-md);
    background: var(--bg-glass);
    backdrop-filter: blur(24px);
    -webkit-backdrop-filter: blur(24px);
    border: 1px solid var(--border-medium);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-normal);
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

.tool-card::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(59, 180, 180, 0.05), transparent);
    opacity: 0;
    transition: opacity var(--transition-normal);
    border-radius: inherit;
}

.tool-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-md);
    border-color: var(--border-strong);
}

.tool-card:hover::before {
    opacity: 1;
}

.tool-card.active {
    border-color: var(--color-teal);
    box-shadow: var(--shadow-sm), var(--shadow-teal-sm);
    transform: translateY(-2px);
}

.tool-card.active::before {
    opacity: 1;
    background: linear-gradient(135deg, rgba(59, 180, 180, 0.08), transparent);
}

.tool-icon {
    font-size: 40px;
    line-height: 1;
    transition: transform var(--transition-normal);
}

.tool-card:hover .tool-icon {
    transform: scale(1.1);
}

.tool-name {
    font-family: var(--font-heading);
    font-size: 14px;
    font-weight: 600;
    color: var(--text-primary);
    text-align: center;
    transition: color var(--transition-fast);
}

.tool-card.active .tool-name {
    color: var(--color-teal);
}

.tool-desc {
    font-size: 11px;
    color: var(--text-tertiary);
    text-align: center;
    line-height: 1.4;
}

/* ----------------------------------------------------------------
   7. Glass Panels (shared)
   ---------------------------------------------------------------- */
.glass-panel {
    background: var(--bg-glass);
    backdrop-filter: blur(24px);
    -webkit-backdrop-filter: blur(24px);
    border: 1px solid var(--border-medium);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    padding: var(--space-lg);
    transition: all var(--transition-normal);
}

.panel-header {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    margin-bottom: var(--space-md);
    padding-bottom: var(--space-md);
    border-bottom: 1px solid var(--border-light);
}

.panel-icon {
    font-size: 20px;
    line-height: 1;
}

.panel-title {
    font-family: var(--font-heading);
    font-size: 15px;
    font-weight: 600;
    color: var(--text-primary);
    flex: 1;
}

/* ----------------------------------------------------------------
   8. Workspace
   ---------------------------------------------------------------- */
.workspace {
    display: flex;
    flex-direction: column;
    gap: var(--space-lg);
    animation: fadeSlideUp 0.6s ease-out 0.2s both;
}

/* ----------------------------------------------------------------
   9. Drop Zone
   ---------------------------------------------------------------- */
.drop-panel {
    padding: var(--space-sm);
}

.drop-zone {
    position: relative;
    border: 2px dashed var(--border-dashed);
    border-radius: var(--radius-md);
    padding: var(--space-2xl) var(--space-lg);
    text-align: center;
    cursor: pointer;
    transition: all var(--transition-normal);
    animation: dropZonePulse 3s ease-in-out infinite;
    min-height: 200px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.drop-zone:hover {
    border-color: var(--color-teal);
    background: rgba(59, 180, 180, 0.03);
    box-shadow: inset 0 0 30px rgba(59, 180, 180, 0.04);
}

.drop-zone.drag-over {
    border-color: var(--color-teal);
    border-style: solid;
    background: rgba(59, 180, 180, 0.06);
    box-shadow: var(--shadow-teal-glow), inset 0 0 40px rgba(59, 180, 180, 0.06);
    transform: scale(1.01);
}

.drop-zone-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-sm);
    pointer-events: none;
}

.drop-icon {
    font-size: 48px;
    line-height: 1;
    margin-bottom: var(--space-xs);
    transition: transform var(--transition-normal);
}

.drop-zone:hover .drop-icon {
    transform: translateY(-4px) scale(1.05);
}

.drop-title {
    font-family: var(--font-heading);
    font-size: 15px;
    font-weight: 600;
    color: var(--text-primary);
}

.drop-subtitle {
    font-size: 12px;
    color: var(--text-tertiary);
}

.drop-formats {
    display: flex;
    gap: var(--space-sm);
    margin-top: var(--space-sm);
    flex-wrap: wrap;
    justify-content: center;
}

.format-tag {
    display: inline-flex;
    align-items: center;
    padding: 3px 10px;
    background: var(--bg-format-tag);
    color: var(--color-teal);
    font-family: var(--font-mono);
    font-size: 11px;
    font-weight: 600;
    border-radius: var(--radius-full);
    border: 1px solid rgba(59, 180, 180, 0.18);
    letter-spacing: 0.5px;
    text-transform: uppercase;
}

#file-input {
    display: none;
}

/* ----------------------------------------------------------------
   10. File List
   ---------------------------------------------------------------- */
.file-list-panel {
    animation: fadeSlideUp 0.3s ease-out both;
}

.file-count,
.page-count {
    font-family: var(--font-mono);
    font-size: 12px;
    font-weight: 500;
    color: var(--color-teal);
    background: var(--bg-format-tag);
    padding: 2px 10px;
    border-radius: var(--radius-full);
    border: 1px solid rgba(59, 180, 180, 0.15);
}

.file-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-xs);
    max-height: 320px;
    overflow-y: auto;
    padding-right: var(--space-xs);
}

.file-item {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    padding: var(--space-sm) var(--space-md);
    background: var(--bg-file-item);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-sm);
    transition: all var(--transition-fast);
    position: relative;
    user-select: none;
}

.file-item:hover {
    background: var(--bg-file-item-hover);
    border-color: var(--border-medium);
}

.file-item.dragging {
    opacity: 0.5;
    outline: 2px dashed var(--color-teal);
    outline-offset: -2px;
}

.file-item.drag-over {
    border-top: 2px solid var(--color-teal);
}

.file-item.drag-over-above {
    border-top: 2px solid var(--color-teal);
}

.file-item.drag-over-below {
    border-bottom: 2px solid var(--color-teal);
}

.drag-handle {
    cursor: grab;
    color: var(--text-tertiary);
    font-size: 14px;
    letter-spacing: -2px;
    line-height: 1;
    padding: var(--space-xs);
    transition: color var(--transition-fast);
    flex-shrink: 0;
}

.drag-handle:hover {
    color: var(--color-teal);
}

.drag-handle:active {
    cursor: grabbing;
}

.file-icon {
    font-size: 22px;
    line-height: 1;
    flex-shrink: 0;
}

.file-info {
    flex: 1;
    min-width: 0;
    display: flex;
    flex-direction: column;
    gap: 1px;
}

.file-name {
    font-size: 13px;
    font-weight: 500;
    color: var(--text-primary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.file-meta {
    font-family: var(--font-mono);
    font-size: 11px;
    color: var(--text-tertiary);
}

.file-remove {
    flex-shrink: 0;
    width: 28px;
    height: 28px;
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    color: var(--text-tertiary);
    transition: all var(--transition-fast);
    background: transparent;
}

.file-remove:hover {
    background: rgba(248, 113, 113, 0.12);
    color: var(--color-error);
    transform: scale(1.1);
}

.file-list-actions {
    display: flex;
    gap: var(--space-sm);
    margin-top: var(--space-md);
    padding-top: var(--space-md);
    border-top: 1px solid var(--border-light);
}

.btn-add-more,
.btn-clear-all {
    display: inline-flex;
    align-items: center;
    gap: var(--space-xs);
    padding: var(--space-sm) var(--space-md);
    font-size: 12px;
    font-weight: 500;
    border-radius: var(--radius-sm);
    transition: all var(--transition-fast);
    border: 1px solid var(--border-light);
    color: var(--text-secondary);
    background: var(--bg-subtle);
}

.btn-add-more:hover {
    color: var(--color-teal);
    border-color: var(--color-teal);
    background: rgba(59, 180, 180, 0.06);
}

.btn-clear-all:hover {
    color: var(--color-error);
    border-color: var(--color-error);
    background: rgba(248, 113, 113, 0.06);
}

.btn-add-more span,
.btn-clear-all span {
    font-size: 14px;
    line-height: 1;
}

/* ----------------------------------------------------------------
   11. Split Options
   ---------------------------------------------------------------- */
.split-options {
    animation: fadeSlideUp 0.3s ease-out both;
}

.split-mode-selector {
    display: flex;
    gap: 0;
    margin-bottom: var(--space-md);
    border-radius: var(--radius-sm);
    overflow: hidden;
    border: 1px solid var(--border-medium);
    background: var(--bg-subtle);
}

.split-mode-btn {
    flex: 1;
    padding: var(--space-sm) var(--space-md);
    font-size: 13px;
    font-weight: 500;
    color: var(--text-secondary);
    background: transparent;
    transition: all var(--transition-fast);
    border-right: 1px solid var(--border-light);
}

.split-mode-btn:last-child {
    border-right: none;
}

.split-mode-btn:hover {
    color: var(--text-primary);
    background: var(--bg-glass-hover);
}

.split-mode-btn.active {
    color: var(--text-inverse);
    background: var(--color-teal);
    font-weight: 600;
}

.split-range-input {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.setting-label {
    font-size: 12px;
    font-weight: 500;
    color: var(--text-secondary);
}

.text-input {
    width: 100%;
    padding: var(--space-sm) var(--space-md);
    font-size: 14px;
    font-family: var(--font-mono);
    color: var(--text-primary);
    background: var(--bg-input);
    border: 1px solid var(--border-input);
    border-radius: var(--radius-sm);
    transition: all var(--transition-fast);
}

.text-input::placeholder {
    color: var(--text-tertiary);
}

.text-input:focus {
    border-color: var(--border-input-focus);
    box-shadow: 0 0 0 3px rgba(59, 180, 180, 0.12);
}

/* ----------------------------------------------------------------
   12. Page Preview Grid
   ---------------------------------------------------------------- */
.preview-panel {
    animation: fadeSlideUp 0.3s ease-out both;
}

.page-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
    gap: var(--space-md);
    max-height: 440px;
    overflow-y: auto;
    padding-right: var(--space-xs);
}

.page-thumb {
    position: relative;
    aspect-ratio: 210 / 297;
    background: var(--bg-surface);
    border: 1px solid var(--border-medium);
    border-radius: var(--radius-sm);
    overflow: hidden;
    cursor: pointer;
    transition: all var(--transition-fast);
    box-shadow: var(--shadow-xs);
}

.page-thumb:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
    border-color: var(--color-teal);
}

.page-thumb.selected {
    border-color: var(--color-teal);
    box-shadow: var(--shadow-teal-sm);
}

.page-thumb canvas,
.page-thumb img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    display: block;
}

.page-number {
    position: absolute;
    bottom: var(--space-xs);
    right: var(--space-xs);
    font-family: var(--font-mono);
    font-size: 10px;
    font-weight: 600;
    color: var(--text-inverse);
    background: rgba(0, 0, 0, 0.55);
    padding: 2px 7px;
    border-radius: var(--radius-full);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    line-height: 1.4;
}

.page-file-label {
    position: absolute;
    top: var(--space-xs);
    left: var(--space-xs);
    right: var(--space-xs);
    font-size: 9px;
    color: var(--text-inverse);
    background: rgba(0, 0, 0, 0.6);
    padding: 2px 6px;
    border-radius: 4px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    backdrop-filter: blur(2px);
    -webkit-backdrop-filter: blur(2px);
    pointer-events: none;
}

.preview-loading,
.preview-error {
    grid-column: 1 / -1;
    text-align: center;
    padding: var(--space-xl);
    font-size: 13px;
    color: var(--text-secondary);
}

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

/* ----------------------------------------------------------------
   13. Process Button
   ---------------------------------------------------------------- */
.btn-process {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
    width: 100%;
    padding: var(--space-md) var(--space-xl);
    background: var(--gradient-orange);
    color: var(--text-inverse);
    font-family: var(--font-heading);
    font-size: 15px;
    font-weight: 700;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-normal);
    box-shadow: var(--shadow-sm);
    position: relative;
    overflow: hidden;
    letter-spacing: 0.3px;
}

.btn-process::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.12), transparent);
    opacity: 0;
    transition: opacity var(--transition-fast);
}

.btn-process:hover:not(:disabled) {
    transform: translateY(-1px);
    box-shadow: var(--shadow-md), var(--shadow-orange-glow);
}

.btn-process:hover:not(:disabled)::before {
    opacity: 1;
}

.btn-process:active:not(:disabled) {
    transform: translateY(0);
    box-shadow: var(--shadow-sm);
}

.btn-process:disabled {
    opacity: 0.4;
    cursor: not-allowed;
    transform: none;
}

.btn-process .btn-icon {
    font-size: 18px;
    line-height: 1;
}

.btn-process.processing .btn-icon {
    animation: spin 1s linear infinite;
}

@keyframes buttonLoadingBar {
    0% { background-position: 200% 0; }
    100% { background-position: -200% 0; }
}

.btn-process.processing {
    background: linear-gradient(90deg, var(--color-orange-start) 0%, #fbbf24 25%, var(--color-orange-start) 50%, #fbbf24 75%, var(--color-orange-start) 100%);
    background-size: 200% 100%;
    animation: buttonLoadingBar 2s linear infinite;
    opacity: 1 !important;
    cursor: wait !important;
}


/* ----------------------------------------------------------------
   14. Progress Bar
   ---------------------------------------------------------------- */
.progress-container {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
    opacity: 0;
    transition: opacity var(--transition-normal);
}

.progress-container.visible {
    opacity: 1;
}

.progress-track {
    width: 100%;
    height: 4px;
    background: var(--bg-progress-track);
    border-radius: var(--radius-full);
    overflow: hidden;
}

.progress-bar {
    height: 100%;
    width: 0%;
    background: var(--gradient-orange);
    border-radius: var(--radius-full);
    transition: width var(--transition-normal);
    position: relative;
}

.progress-bar::after {
    content: '';
    position: absolute;
    right: 0;
    top: 0;
    bottom: 0;
    width: 40px;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.35));
    border-radius: var(--radius-full);
    animation: pulse 1.5s ease-in-out infinite;
}

.progress-text {
    font-family: var(--font-mono);
    font-size: 12px;
    font-weight: 500;
    color: var(--text-secondary);
    text-align: center;
}

/* ----------------------------------------------------------------
   15. Privacy Banner
   ---------------------------------------------------------------- */
.privacy-banner {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
    padding: var(--space-md) var(--space-lg);
    background: var(--bg-privacy);
    border: 1px solid rgba(59, 180, 180, 0.12);
    border-radius: var(--radius-md);
    text-align: center;
    animation: fadeSlideUp 0.6s ease-out 0.3s both;
}

.privacy-icon {
    font-size: 18px;
    line-height: 1;
    flex-shrink: 0;
}

.privacy-banner span:last-child {
    font-size: 13px;
    color: var(--text-secondary);
    line-height: 1.5;
}

.privacy-banner strong {
    color: var(--color-teal);
    font-weight: 600;
}

/* ----------------------------------------------------------------
   16. Footer
   ---------------------------------------------------------------- */
.app-footer {
    text-align: center;
    padding: var(--space-lg) 0 var(--space-md);
    animation: fadeSlideUp 0.6s ease-out 0.4s both;
}

.app-footer p {
    font-size: 12px;
    color: var(--text-tertiary);
    line-height: 1.5;
}

.app-footer a {
    color: var(--color-teal);
    font-weight: 500;
    transition: color var(--transition-fast);
}

.app-footer a:hover {
    color: var(--color-teal-light);
}

/* ----------------------------------------------------------------
   17. Notifications
   ---------------------------------------------------------------- */
.notifications {
    position: fixed;
    bottom: var(--space-lg);
    right: var(--space-lg);
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
    z-index: 9999;
    pointer-events: none;
    max-width: 380px;
    width: 100%;
}

.notification {
    display: flex;
    align-items: flex-start;
    gap: var(--space-sm);
    padding: var(--space-md);
    background: var(--bg-notification);
    border: 1px solid var(--border-medium);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    animation: notificationSlideIn 0.4s cubic-bezier(0.16, 1, 0.3, 1) both;
    pointer-events: auto;
    position: relative;
    overflow: hidden;
}

.notification::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 3px;
}

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

.notification.error::before {
    background: var(--color-error);
}

.notification.info::before {
    background: var(--color-info);
}

.notification.warning::before {
    background: var(--color-warning);
}

.notification-icon {
    font-size: 18px;
    line-height: 1;
    flex-shrink: 0;
    margin-top: 1px;
}

.notification-content {
    flex: 1;
    min-width: 0;
}

.notification-title {
    font-family: var(--font-heading);
    font-size: 13px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 2px;
}

.notification-message {
    font-size: 12px;
    color: var(--text-secondary);
    line-height: 1.4;
}

.notification-close {
    flex-shrink: 0;
    width: 24px;
    height: 24px;
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    color: var(--text-tertiary);
    transition: all var(--transition-fast);
    cursor: pointer;
}

.notification-close:hover {
    background: var(--bg-subtle);
    color: var(--text-primary);
}

.notification.removing {
    animation: notificationSlideOut 0.35s cubic-bezier(0.55, 0, 1, 0.45) both;
}

/* ----------------------------------------------------------------
   18. Keyframe Animations
   ---------------------------------------------------------------- */
@keyframes fadeSlideUp {
    from {
        opacity: 0;
        transform: translateY(16px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes dropZonePulse {
    0%, 100% {
        border-color: var(--border-dashed);
    }
    50% {
        border-color: rgba(59, 180, 180, 0.35);
    }
}

@keyframes logoPulse {
    0%, 100% {
        filter: drop-shadow(0 2px 6px rgba(228, 121, 17, 0.3));
    }
    50% {
        filter: drop-shadow(0 2px 12px rgba(228, 121, 17, 0.5));
    }
}

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

@keyframes pulse {
    0%, 100% {
        opacity: 0.5;
    }
    50% {
        opacity: 1;
    }
}

@keyframes notificationSlideIn {
    from {
        opacity: 0;
        transform: translateX(100%) scale(0.95);
    }
    to {
        opacity: 1;
        transform: translateX(0) scale(1);
    }
}

@keyframes notificationSlideOut {
    from {
        opacity: 1;
        transform: translateX(0) scale(1);
    }
    to {
        opacity: 0;
        transform: translateX(100%) scale(0.95);
    }
}

@keyframes shimmer {
    0% {
        background-position: -200% 0;
    }
    100% {
        background-position: 200% 0;
    }
}

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

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* ----------------------------------------------------------------
   20. Responsive — Tablet (max-width: 768px)
   ---------------------------------------------------------------- */
@media (max-width: 768px) {
    .app-container {
        padding: var(--space-md);
        gap: var(--space-md);
    }

    .tool-selector {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--space-sm);
    }

    .tool-card {
        padding: var(--space-md) var(--space-sm);
    }

    .tool-icon {
        font-size: 32px;
    }

    .tool-name {
        font-size: 13px;
    }

    .tool-desc {
        font-size: 10px;
    }

    .logo-text {
        font-size: 26px;
    }

    .logo-icon {
        font-size: 36px;
    }

    .app-subtitle {
        font-size: 13px;
    }

    .drop-zone {
        padding: var(--space-xl) var(--space-md);
        min-height: 160px;
    }

    .drop-icon {
        font-size: 40px;
    }

    .drop-title {
        font-size: 14px;
    }

    .page-grid {
        grid-template-columns: repeat(auto-fill, minmax(100px, 1fr));
        gap: var(--space-sm);
    }

    .btn-process {
        font-size: 14px;
        padding: var(--space-md) var(--space-lg);
    }

    .privacy-banner {
        flex-direction: column;
        gap: var(--space-xs);
    }

    .notifications {
        right: var(--space-md);
        left: var(--space-md);
        max-width: none;
        bottom: var(--space-md);
    }
}

/* ----------------------------------------------------------------
   21. Responsive — Mobile (max-width: 480px)
   ---------------------------------------------------------------- */
@media (max-width: 480px) {
    .app-container {
        padding: var(--space-sm);
        gap: var(--space-sm);
    }

    .tool-selector {
        grid-template-columns: 1fr;
        gap: var(--space-sm);
    }

    .tool-card {
        flex-direction: row;
        padding: var(--space-sm) var(--space-md);
        gap: var(--space-md);
        text-align: left;
        align-items: center;
    }

    .tool-icon {
        font-size: 28px;
    }

    .tool-name {
        font-size: 13px;
    }

    .tool-desc {
        font-size: 10px;
        text-align: left;
    }

    .app-header {
        padding: var(--space-lg) var(--space-md);
    }

    .logo-text {
        font-size: 22px;
    }

    .logo-icon {
        font-size: 30px;
    }

    .app-subtitle {
        font-size: 12px;
    }

    .logo {
        gap: var(--space-sm);
    }

    .glass-panel {
        padding: var(--space-md);
    }

    .drop-zone {
        padding: var(--space-lg) var(--space-md);
        min-height: 140px;
    }

    .drop-icon {
        font-size: 36px;
    }

    .drop-title {
        font-size: 13px;
    }

    .drop-subtitle {
        font-size: 11px;
    }

    .panel-title {
        font-size: 13px;
    }

    .btn-process {
        font-size: 13px;
        padding: var(--space-sm) var(--space-md);
    }

    .file-list-actions {
        flex-direction: column;
    }

    .page-grid {
        grid-template-columns: repeat(auto-fill, minmax(80px, 1fr));
    }

    .theme-toggle {
        width: 34px;
        height: 34px;
        font-size: 16px;
        top: var(--space-sm);
        right: var(--space-sm);
    }

    .notification {
        padding: var(--space-sm);
    }

    .notification-title {
        font-size: 12px;
    }

    .notification-message {
        font-size: 11px;
    }
}

/* ----------------------------------------------------------------
   21.5. New Components (Download Panel, Drag Indicators, Page Removal)
   ---------------------------------------------------------------- */
.download-panel {
    animation: fadeSlideUp 0.4s ease-out both;
}

.download-content {
    display: flex;
    align-items: center;
    gap: var(--space-lg);
    padding: var(--space-md) 0;
}

.download-file-icon {
    font-size: 64px;
    line-height: 1;
    filter: drop-shadow(0 4px 12px rgba(0, 0, 0, 0.15));
    animation: logoPulse 3s ease-in-out infinite;
}

.download-file-details {
    display: flex;
    flex-direction: column;
    gap: var(--space-xs);
    flex: 1;
    min-width: 0;
}

.download-filename {
    font-family: var(--font-heading);
    font-size: 16px;
    font-weight: 600;
    color: var(--text-primary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.download-filesize {
    font-family: var(--font-mono);
    font-size: 13px;
    color: var(--text-secondary);
}

.download-actions {
    display: flex;
    align-items: center;
    gap: var(--space-md);
}

@keyframes pulsatingGlow {
    0%, 100% {
        box-shadow: 0 0 8px rgba(228, 121, 17, 0.4);
    }
    50% {
        box-shadow: 0 0 16px rgba(228, 121, 17, 0.8);
    }
}

.btn-download {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
    padding: var(--space-md) var(--space-xl);
    background: var(--gradient-orange);
    color: var(--text-inverse);
    font-family: var(--font-heading);
    font-size: 15px;
    font-weight: 700;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-normal);
    box-shadow: var(--shadow-sm);
    position: relative;
    overflow: hidden;
    animation: pulsatingGlow 2s infinite ease-in-out;
}

.btn-download::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.12), transparent);
    opacity: 0;
    transition: opacity var(--transition-fast);
}

.btn-download:hover {
    transform: translateY(-1px);
    box-shadow: var(--shadow-md), var(--shadow-orange-glow);
}

.btn-download:hover::before {
    opacity: 1;
}

.btn-download:active {
    transform: translateY(0);
    box-shadow: var(--shadow-sm);
}

.btn-reset {
    display: inline-flex;
    align-items: center;
    gap: var(--space-xs);
    padding: var(--space-md) var(--space-xl);
    font-size: 14px;
    font-weight: 600;
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
    border: 1px solid var(--border-medium);
    color: var(--text-secondary);
    background: var(--bg-subtle);
}

.btn-reset:hover {
    color: var(--color-teal);
    border-color: var(--color-teal);
    background: rgba(59, 180, 180, 0.06);
}

/* Page Thumbnail drag and delete styles */
.page-thumb.dragging {
    opacity: 0.4;
    border: 2px dashed var(--color-teal) !important;
}

.page-thumb.drag-over-left {
    border-left: 5px solid var(--color-teal) !important;
    transform: scale(1.02);
}

.page-thumb.drag-over-right {
    border-right: 5px solid var(--color-teal) !important;
    transform: scale(1.02);
}

.page-thumb-remove {
    position: absolute;
    top: 6px;
    right: 6px;
    width: 22px;
    height: 22px;
    border-radius: var(--radius-full);
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 11px;
    cursor: pointer;
    z-index: 10;
    transition: all var(--transition-fast);
    opacity: 0.7;
}

.page-thumb:hover .page-thumb-remove {
    opacity: 1;
}

.page-thumb-remove:hover {
    background: var(--color-error);
    border-color: var(--color-error);
    transform: scale(1.15);
}

@media (max-width: 768px) {
    .download-content {
        flex-direction: column;
        text-align: center;
        gap: var(--space-md);
    }
    
    .download-file-details {
        align-items: center;
    }
    
    .download-actions {
        flex-direction: column;
        width: 100%;
        gap: var(--space-sm);
    }
    
    .btn-download, .btn-reset {
        width: 100%;
    }
}

/* ----------------------------------------------------------------
   22. Print Styles
   ---------------------------------------------------------------- */
@media print {
    body {
        background: #fff;
    }

    .theme-toggle,
    .notifications,
    .btn-process,
    .progress-container {
        display: none !important;
    }
}