/* ===================================
   CSS Variables
   =================================== */
:root {
    /* Colors */
    --color-primary: #2563eb;
    --color-primary-hover: #1d4ed8;
    --color-success: #16a34a;
    --color-success-hover: #15803d;
    --color-warning: #eab308;
    --color-error: #dc2626;
    --color-secondary: #6b7280;
    --color-secondary-hover: #4b5563;

    --color-bg: #f9fafb;
    --color-surface: #ffffff;
    --color-border: #e5e7eb;
    --color-text: #111827;
    --color-text-light: #6b7280;

    /* Traffic light colors */
    --color-red: #dc2626;
    --color-yellow: #eab308;
    --color-green: #16a34a;

    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 0.9rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;

    /* Font sizes */
    --font-xs: 0.75rem;
    --font-sm: 0.875rem;
    --font-md: 1rem;
    --font-lg: 1.125rem;
    --font-xl: 1.25rem;
    --font-2xl: 1.5rem;
    --font-3xl: 2rem;

    /* Border radius */
    --radius-sm: 0.25rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;
    --transition-slow: 350ms ease;

    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
}

/* ===================================
   Base Styles
   =================================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background-color: var(--color-bg);
    color: var(--color-text);
    line-height: 1.6;
    padding: var(--spacing-md);
}

/* ===================================
   Layout
   =================================== */
.header {
    text-align: center;
    margin-bottom: var(--spacing-2xl);
    padding: var(--spacing-xl) 0;
}

.header h1 {
    font-size: var(--font-3xl);
    color: var(--color-primary);
    margin-bottom: var(--spacing-sm);
}

.subtitle {
    font-size: var(--font-lg);
    color: var(--color-text-light);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
}

/* ===================================
   Privacy Notice
   =================================== */
.privacy-notice {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
    text-align: center;
    box-shadow: var(--shadow-md);
}

.privacy-notice p {
    margin: 0;
    font-size: var(--font-md);
    line-height: 1.8;
}

.privacy-notice strong {
    font-weight: 700;
}

.install-note {
    margin-top: var(--spacing-md);
    opacity: 0.9;
}

/* ===================================
   Quick Presets
   =================================== */
.quick-presets {
    background: var(--color-surface);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
    box-shadow: var(--shadow-md);
}

.quick-presets h3 {
    font-size: var(--font-lg);
    margin-bottom: var(--spacing-lg);
    color: var(--color-text);
}

.preset-buttons {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-md);
}

.btn-preset {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: var(--spacing-lg);
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-base);
    box-shadow: var(--shadow-sm);
}

.btn-preset:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.btn-preset:active {
    transform: translateY(-2px);
}

.preset-title {
    font-size: var(--font-lg);
    font-weight: 700;
    margin-bottom: var(--spacing-xs);
}

.preset-specs {
    font-size: var(--font-sm);
    opacity: 0.9;
}

/* ===================================
   Custom Dimensions
   =================================== */
.dimensions-config {
    background: var(--color-surface);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
    box-shadow: var(--shadow-md);
}

.dimensions-config summary {
    font-size: var(--font-md);
    font-weight: 600;
    cursor: pointer;
    padding: var(--spacing-sm);
    list-style: none;
    color: var(--color-secondary);
}

.dimensions-config summary::-webkit-details-marker {
    display: none;
}

.dimensions-config summary::before {
    content: '▶';
    margin-right: var(--spacing-sm);
    transition: transform var(--transition-base);
    display: inline-block;
}

.dimensions-config details[open] summary::before {
    transform: rotate(90deg);
}

.dimensions-inputs {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-md);
    padding: var(--spacing-lg);
    margin-top: var(--spacing-md);
}

.dimensions-inputs label {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
    font-size: var(--font-sm);
    color: var(--color-text);
}

.dimensions-inputs input[type="number"] {
    padding: var(--spacing-sm);
    border: 2px solid var(--color-border);
    border-radius: var(--radius-sm);
    font-size: var(--font-md);
    width: 80px;
}

.dimensions-inputs input[type="number"]:focus {
    outline: none;
    border-color: var(--color-primary);
}

#applyDimensionsBtn {
    grid-column: 1 / -1;
    justify-self: start;
}

/* ===================================
   Requirements Panel
   =================================== */
.requirements-panel {
    background: var(--color-surface);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
    box-shadow: var(--shadow-md);
}

.requirements-panel h2 {
    font-size: var(--font-xl);
    margin-bottom: var(--spacing-lg);
    color: var(--color-text);
}

.checklist {
    list-style: none;
    margin-bottom: var(--spacing-xl);
}

.checklist-item {
    display: flex;
    align-items: center;
    padding: var(--spacing-md);
    margin-bottom: var(--spacing-sm);
    background: var(--color-bg);
    border-radius: var(--radius-md);
    transition: background var(--transition-fast);
}

.checklist-item.valid {
    background: #f0fdf4;
    border-left: 4px solid var(--color-success);
}

.checklist-item.invalid {
    background: #fef2f2;
    border-left: 4px solid var(--color-error);
}

.checklist-item.warning {
    background: #fefce8;
    border-left: 4px solid var(--color-warning);
}

.checkbox {
    font-size: var(--font-2xl);
    margin-right: var(--spacing-md);
    min-width: 1.5rem;
}

.requirement-text {
    flex: 1;
    font-size: var(--font-md);
}

.file-size-display {
    font-size: var(--font-sm);
    color: var(--color-text-light);
    margin-left: var(--spacing-sm);
}

/* Status Indicator */
.status-indicator {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-lg);
    background: var(--color-bg);
    border-radius: var(--radius-md);
}

.traffic-light {
    width: 3rem;
    height: 3rem;
    border-radius: 50%;
    background: var(--color-secondary);
    transition: background var(--transition-base);
    flex-shrink: 0;
}

.traffic-light.red {
    background: var(--color-red);
    box-shadow: 0 0 20px rgba(220, 38, 38, 0.5);
}

.traffic-light.yellow {
    background: var(--color-yellow);
    box-shadow: 0 0 20px rgba(234, 179, 8, 0.5);
}

.traffic-light.green {
    background: var(--color-green);
    box-shadow: 0 0 20px rgba(22, 163, 74, 0.5);
}

.status-message {
    font-size: var(--font-lg);
    color: var(--color-text);
    min-height: 52px;
    display: flex;
    align-items: center;
}

/* ===================================
   Upload Section
   =================================== */
.upload-section {
    margin-bottom: var(--spacing-xl);
}

.upload-zone {
    background: var(--color-surface);
    border: 3px dashed var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--spacing-2xl);
    text-align: center;
    transition: all var(--transition-base);
}

.upload-zone.drag-over {
    border-color: var(--color-primary);
    background: #dbeafe;
    transform: scale(1.02);
}

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

.frame-preview {
    width: 100%;
    max-width: 320px;
    margin: 0 auto var(--spacing-md);
    display: flex;
    justify-content: center;
    align-items: center;
}

.frame-outline {
    width: 100%;
    aspect-ratio: 1 / 1;
    border: 2px solid var(--color-primary);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--font-2xl);
    color: var(--color-text-light);
    background: #f8fafc;
    padding: var(--spacing-md);
    box-sizing: border-box;
}

.upload-text {
    font-size: var(--font-xl);
    color: var(--color-text);
    font-weight: 500;
}

.upload-hint {
    font-size: var(--font-sm);
    color: var(--color-text-light);
}

/* ===================================
   Editor Section
   =================================== */
.editor-section {
    background: var(--color-surface);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
    box-shadow: var(--shadow-md);
}


.canvas-container {
    --canvas-target-width: 200px;
    --canvas-target-height: 200px;
    position: relative;
    width: min(100%, var(--canvas-target-width));
    height: auto;
    max-width: min(var(--canvas-target-width), calc(100vw - 2rem));
    max-height: min(var(--canvas-target-height), 70vh); /* Clamp display height on mobile */
    margin: 0 auto var(--spacing-xl);
    border: 2px solid var(--color-border);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden; /* Ensure content stays within bounds */
}

#photoCanvas {
    display: block;
    max-width: 100%;
    max-height: 100%;
    width: auto;
    height: auto;
    object-fit: contain; /* Maintain aspect ratio */
}

.canvas-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    border: 2px dashed rgba(255, 255, 255, 0.5);
    pointer-events: none;
}

/* Controls Panel */
.controls-panel {
    max-width: 500px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

.control-card {
    background: #f8fafc;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    box-shadow: inset 0 1px 0 rgb(255 255 255 / 0.5);
}

.control-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--spacing-md);
}

.control-label {
    font-weight: 600;
    color: var(--color-text);
}

.control-value {
    font-size: var(--font-lg);
    font-weight: 600;
    color: var(--color-primary);
}

#zoomInput {
    width: 90px;
    padding: var(--spacing-sm);
    border: 2px solid var(--color-border);
    border-radius: var(--radius-sm);
    font-size: var(--font-md);
    text-align: center;
    font-weight: 600;
}

#zoomInput:focus {
    outline: none;
    border-color: var(--color-primary);
}

input[type="range"] {
    flex: 1;
    height: 8px;
    background: var(--color-border);
    border-radius: var(--radius-xl);
    outline: none;
    -webkit-appearance: none;
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 24px;
    height: 24px;
    background: var(--color-primary);
    cursor: pointer;
    border-radius: 50%;
    transition: background var(--transition-fast);
}

input[type="range"]::-webkit-slider-thumb:hover {
    background: var(--color-primary-hover);
}

input[type="range"]::-moz-range-thumb {
    width: 24px;
    height: 24px;
    background: var(--color-primary);
    cursor: pointer;
    border-radius: 50%;
    border: none;
    transition: background var(--transition-fast);
}

input[type="range"]::-moz-range-thumb:hover {
    background: var(--color-primary-hover);
}

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

.btn-zoom {
    width: 48px;
    height: 48px;
    border: 2px solid var(--color-border);
    border-radius: var(--radius-md);
    background: var(--color-surface);
    font-size: var(--font-2xl);
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
}

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

.zoom-hints {
    display: flex;
    align-items: center;
    justify-content: space-between;
    font-size: var(--font-sm);
    color: var(--color-text-light);
    margin-top: var(--spacing-sm);
}

.precision-control {
    margin-top: var(--spacing-md);
    border-top: 1px solid var(--color-border);
    padding-top: var(--spacing-md);
}

.precision-control summary {
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.precision-control summary::-webkit-details-marker {
    display: none;
}

.precision-control summary::after {
    content: '▾';
    font-size: var(--font-sm);
    color: var(--color-text-light);
    display: inline-block;
    transition: transform var(--transition-fast);
}

.precision-control[open] summary::after {
    transform: rotate(180deg);
}

.precision-control label {
    display: block;
    margin: var(--spacing-sm) 0;
    font-size: var(--font-sm);
    color: var(--color-text-light);
}

.position-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(44px, 1fr));
    gap: var(--spacing-md);
    place-items: center;
}

.grid-spacer {
    width: 100%;
    height: 0;
}

.btn-control {
    width: 44px;
    height: 44px;
    border: 2px solid var(--color-border);
    background: var(--color-surface);
    border-radius: var(--radius-md);
    font-size: var(--font-xl);
    cursor: pointer;
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
}

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

.btn-control:active {
    transform: scale(0.95);
}

.btn-center {
    width: 44px;
    height: 44px;
    padding: 0;
    font-size: var(--font-lg);
    font-weight: 600;
}

.icon-center {
    width: 26px;
    height: 26px;
    border: 2px solid currentColor;
    border-radius: 50%;
    display: inline-block;
    position: relative;
}

.icon-center::before,
.icon-center::after {
    content: '';
    position: absolute;
    background: currentColor;
}

.icon-center::before {
    width: 2px;
    top: 4px;
    bottom: 4px;
    left: 50%;
    transform: translateX(-50%);
}

.icon-center::after {
    height: 2px;
    left: 4px;
    right: 4px;
    top: 50%;
    transform: translateY(-50%);
}

.reset-card .reset-actions {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-md);
}

/* ===================================
   Buttons
   =================================== */
.btn {
    padding: var(--spacing-md) var(--spacing-xl);
    border: none;
    border-radius: var(--radius-md);
    font-size: var(--font-md);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
    display: inline-block;
    text-align: center;
}

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

.btn-primary:hover {
    background: var(--color-primary-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background: var(--color-secondary);
    color: white;
    margin-right: var(--spacing-sm);
}

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

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

.btn-success:hover {
    background: var(--color-success-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-large {
    padding: var(--spacing-lg) var(--spacing-2xl);
    font-size: var(--font-lg);
}

.btn:active {
    transform: scale(0.98);
}

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

/* ===================================
   Download Section
   =================================== */
.download-section {
    background: var(--color-surface);
    border-radius: var(--radius-lg);
    padding: var(--spacing-2xl);
    margin-bottom: var(--spacing-xl);
    text-align: center;
    box-shadow: var(--shadow-md);
}

.download-section h2 {
    color: var(--color-success);
    margin-bottom: var(--spacing-xl);
    font-size: var(--font-2xl);
}

.download-options {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    margin-bottom: var(--spacing-lg);
    flex-wrap: wrap;
}

/* ===================================
   Help Section
   =================================== */
.help-section {
    background: var(--color-surface);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
    box-shadow: var(--shadow-md);
}

.help-section summary {
    font-size: var(--font-lg);
    font-weight: 600;
    cursor: pointer;
    padding: var(--spacing-md);
    list-style: none;
    color: var(--color-primary);
}

.help-section summary::-webkit-details-marker {
    display: none;
}

.help-section summary::before {
    content: '▶';
    margin-right: var(--spacing-sm);
    transition: transform var(--transition-base);
    display: inline-block;
}

.help-section details[open] summary::before {
    transform: rotate(90deg);
}

.examples-content {
    padding: var(--spacing-lg);
}

.examples-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
}

.example-item {
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
}

.example-item.good {
    background: #f0fdf4;
    border: 2px solid var(--color-success);
}

.example-item.bad {
    background: #fef2f2;
    border: 2px solid var(--color-error);
}

.example-label {
    font-weight: 700;
    font-size: var(--font-lg);
    margin-bottom: var(--spacing-md);
}

.good-label {
    color: var(--color-success);
}

.bad-label {
    color: var(--color-error);
}

.example-item ul {
    list-style-position: inside;
}

.example-item li {
    margin-bottom: var(--spacing-sm);
}

.tips {
    background: #eff6ff;
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    border-left: 4px solid var(--color-primary);
}

.tips h3 {
    color: var(--color-primary);
    margin-bottom: var(--spacing-md);
}

.tips ul {
    list-style-position: inside;
}

.tips li {
    margin-bottom: var(--spacing-sm);
}

/* ===================================
   Footer
   =================================== */
.footer {
    text-align: center;
    padding: var(--spacing-xl);
    color: var(--color-text-light);
    font-size: var(--font-sm);
}

.footer p {
    margin: var(--spacing-xs) 0;
}

.version-info {
    font-size: var(--font-xs);
    opacity: 0.7;
}

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

.active {
    opacity: 1;
}

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

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

.warning {
    color: var(--color-warning);
}

.disabled {
    opacity: 0.5;
    pointer-events: none;
}

/* ===================================
   Toast Notifications
   =================================== */
.toast-container {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 10000;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    pointer-events: none;
}

.toast {
    min-width: 300px;
    max-width: 500px;
    padding: var(--spacing-lg);
    background: white;
    border-radius: var(--radius-lg);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    animation: slideIn 0.3s ease;
    pointer-events: auto;
    position: relative;
}

.toast.info {
    border-left: 4px solid var(--color-primary);
}

.toast.success {
    border-left: 4px solid var(--color-success);
}

.toast.warning {
    border-left: 4px solid var(--color-warning);
}

.toast.error {
    border-left: 4px solid var(--color-error);
}

.toast-icon {
    font-size: var(--font-2xl);
    flex-shrink: 0;
}

.toast.info .toast-icon {
    color: var(--color-primary);
}

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

.toast.warning .toast-icon {
    color: var(--color-warning);
}

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

.toast-message {
    flex: 1;
    font-size: var(--font-md);
    color: var(--color-text);
    line-height: 1.5;
}

.toast-close {
    background: none;
    border: none;
    font-size: var(--font-xl);
    color: var(--color-text-light);
    cursor: pointer;
    padding: 0;
    width: 24px;
    height: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-sm);
    transition: all var(--transition-fast);
}

.toast-close:hover {
    background: var(--color-bg);
    color: var(--color-text);
}

.toast.hiding {
    animation: slideOut 0.3s ease forwards;
}

@keyframes slideIn {
    from {
        transform: translateX(400px);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

@keyframes slideOut {
    from {
        transform: translateX(0);
        opacity: 1;
    }
    to {
        transform: translateX(400px);
        opacity: 0;
    }
}