:root {
    /* Base Colors */
    --bg-primary: #FFFFFF;
    --text-primary: #000000;
    --text-secondary: #666666;
    --border-color: #E5E5E5;
    --accent-color: #000000;
    --surface-color: #F8F9FA;
    --surface-hover: #F1F3F5;
    
    /* Device/Mockup Colors (Updated via JS) */
    --device-bg: #000000;
    --device-text: #FFFFFF;
    --device-accent: #E5E5E5;

    /* Typography */
    --font-sans: 'Plus Jakarta Sans', 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-serif: 'EB Garamond', Georgia, serif;
    
    /* Variables */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 24px;
    --transition-fast: 0.2s ease;
    --transition-med: 0.4s ease;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: var(--font-sans);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
    min-height: 100vh;
}

/* App Wrapper */
.app-wrapper {
    max-width: 800px;
    margin: 0 auto;
    width: 100%;
    padding: 2rem 1.5rem;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    gap: 3rem;
}

.hidden {
    display: none !important;
}

/* Header */
.app-header {
    display: flex;
    justify-content: center;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 1rem;
}

.logo-text {
    font-size: 1.25rem;
    font-weight: 700;
    letter-spacing: -0.02em;
}

/* Base Buttons */
.generate-btn {
    width: 100%;
    padding: 1.25rem;
    background: var(--text-primary);
    color: var(--bg-primary);
    border: none;
    border-radius: var(--radius-md);
    font-family: inherit;
    font-size: 1.125rem;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.1s ease, opacity var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.generate-btn:hover {
    opacity: 0.9;
}

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

.secondary-btn {
    padding: 0.75rem 1.25rem;
    background: var(--bg-primary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-family: inherit;
    font-weight: 600;
    cursor: pointer;
    transition: background var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

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

.secondary-btn.icon-only {
    width: 3rem;
    height: 3rem;
    padding: 0;
}

/* Base Inputs */
.dropdown-wrapper {
    position: relative;
    width: 100%;
}

.minimal-select {
    width: 100%;
    -webkit-appearance: none;
    -moz-appearance: none;
    appearance: none;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    padding: 1rem 3rem 1rem 1rem;
    border-radius: var(--radius-md);
    font-family: inherit;
    font-size: 1rem;
    font-weight: 500;
    color: var(--text-primary);
    cursor: pointer;
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.minimal-select:focus {
    outline: none;
    border-color: var(--text-primary);
    box-shadow: 0 0 0 1px var(--text-primary);
}

.dropdown-icon {
    position: absolute;
    right: 1.25rem;
    top: 50%;
    transform: translateY(-50%);
    pointer-events: none;
    color: var(--text-secondary);
}

.section-label {
    display: block;
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-primary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 0.5rem;
}

.section-hint {
    margin-top: -0.25rem;
    margin-bottom: 0.85rem;
    color: var(--text-secondary);
    font-size: 0.9rem;
    font-weight: 500;
}

.input-section {
    margin-bottom: 1.5rem;
}

.customization-panel {
    padding-top: 0.25rem;
}

.action-section {
    margin-top: 0.75rem;
}

/* Device picker (OS buttons + search) */
.device-picker {
    width: 100%;
}

.device-os-toggle {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.75rem;
}

.os-btn {
    padding: 0.9rem 1rem;
    background: var(--bg-primary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    border-radius: 999px;
    font-family: inherit;
    font-size: 0.95rem;
    font-weight: 700;
    cursor: pointer;
    transition: background var(--transition-fast), border-color var(--transition-fast), transform 0.1s ease, color var(--transition-fast);
}

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

.os-btn:active {
    transform: scale(0.99);
}

.os-btn.active {
    background: var(--text-primary);
    color: var(--bg-primary);
    border-color: var(--text-primary);
}

.os-btn.error {
    border-color: #DC2626;
    box-shadow: 0 0 0 1px #DC2626;
}

.device-search-input.error {
    border-color: #DC2626;
    box-shadow: 0 0 0 1px #DC2626;
}

.shake {
    animation: shakeX 0.35s ease-in-out;
}

@keyframes shakeX {
    0% { transform: translateX(0); }
    15% { transform: translateX(-6px); }
    30% { transform: translateX(6px); }
    45% { transform: translateX(-5px); }
    60% { transform: translateX(5px); }
    75% { transform: translateX(-3px); }
    90% { transform: translateX(3px); }
    100% { transform: translateX(0); }
}

.device-search {
    margin-top: 1rem;
    animation: fadeSlideIn 0.25s ease;
}

@keyframes fadeSlideIn {
    from { opacity: 0; transform: translateY(-6px); }
    to { opacity: 1; transform: translateY(0); }
}

.device-search-row {
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 0.75rem;
    align-items: center;
}

.device-search-input-wrap {
    position: relative;
    width: 100%;
}

.device-search-icon {
    position: absolute;
    left: 1rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-secondary);
    pointer-events: none;
}

.device-search-input {
    width: 100%;
    padding: 0.95rem 1rem 0.95rem 2.75rem;
    border-radius: 999px;
    border: 1px solid var(--border-color);
    background: var(--bg-primary);
    font-family: inherit;
    font-size: 0.95rem;
    font-weight: 500;
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.device-search-input:focus {
    outline: none;
    border-color: var(--text-primary);
    box-shadow: 0 0 0 1px var(--text-primary);
}

.device-confirm-btn {
    padding: 0.95rem 1.25rem;
    border-radius: 999px;
    border: 1px solid var(--text-primary);
    background: var(--text-primary);
    color: var(--bg-primary);
    font-family: inherit;
    font-weight: 700;
    cursor: pointer;
    transition: opacity var(--transition-fast), transform 0.1s ease;
    white-space: nowrap;
}

.device-confirm-btn:hover {
    opacity: 0.9;
}

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

.device-suggestions {
    margin-top: 0.85rem;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 18px;
    overflow: hidden;
    max-height: 240px;
    overflow-y: auto;
}

.device-suggestions.hidden {
    display: none !important;
}

.device-suggestion-item {
    padding: 0.9rem 1rem;
    display: flex;
    justify-content: space-between;
    gap: 1rem;
    align-items: baseline;
    cursor: pointer;
    transition: background var(--transition-fast);
    border-bottom: 1px solid var(--border-color);
}

.device-suggestion-item:last-child {
    border-bottom: none;
}

.device-suggestion-item:hover {
    background: var(--surface-color);
}

.device-suggestion-item.active {
    background: var(--surface-hover);
}

.device-suggestion-name {
    font-weight: 700;
    font-size: 0.95rem;
}

.device-suggestion-meta {
    font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
    color: var(--text-secondary);
    font-size: 0.8rem;
}

.custom-resolution {
    margin-top: 0.85rem;
    padding: 0.85rem;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 18px;
}

.custom-resolution.error {
    border-color: #DC2626;
    box-shadow: 0 0 0 1px #DC2626;
}

.custom-resolution-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.75rem;
}

.custom-resolution-input {
    padding: 0.85rem 0.9rem;
    border-radius: 999px;
    border: 1px solid var(--border-color);
    background: var(--surface-color);
    font-family: inherit;
    font-size: 0.95rem;
    font-weight: 600;
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.custom-resolution-input.error {
    border-color: #DC2626;
    box-shadow: 0 0 0 1px #DC2626;
}

.custom-resolution-input:focus {
    outline: none;
    border-color: var(--text-primary);
    box-shadow: 0 0 0 1px var(--text-primary);
}

.custom-resolution-hint {
    margin-top: 0.6rem;
    color: var(--text-secondary);
    font-size: 0.825rem;
}

.device-selected-meta {
    margin-top: 0.65rem;
    font-size: 0.85rem;
    color: var(--text-secondary);
}

/* -------------------------
 * View 1: Landing Page
 * ------------------------- */

/* Hero Section */
.hero-section {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 2rem;
    text-align: center;
}

.hero-title {
    font-size: clamp(2rem, 5vw, 3.5rem);
    font-weight: 700;
    line-height: 1.1;
    letter-spacing: -0.04em;
    margin-bottom: 0.75rem;
}

.hero-subtitle {
    font-size: 1.125rem;
    color: var(--text-secondary);
    font-weight: 500;
}

/* Shuffle Album (Mockup) */
.shuffle-album-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
    width: 100%;
}

.iphone-mockup {
    position: relative;
    width: 280px;
    height: 606px;
    background: #000;
    border-radius: 40px;
    padding: 10px;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.2), 
                0 0 0 1px rgba(0,0,0,0.05) inset;
}

@media (min-width: 768px) {
    .iphone-mockup {
        width: 300px;
        height: 650px;
        border-radius: 44px;
        padding: 12px;
    }
}

.iphone-screen {
    position: relative;
    width: 100%;
    height: 100%;
    background-color: var(--device-bg);
    border-radius: 32px;
    overflow: hidden;
    color: var(--device-text);
    display: flex;
    flex-direction: column;
}

.fade-element {
    transition: opacity 1s ease-in-out;
}

.fade-out {
    opacity: 0;
}

.dynamic-island {
    position: absolute;
    top: 10px;
    left: 50%;
    transform: translateX(-50%);
    width: 90px;
    height: 28px;
    background: #000;
    border-radius: 20px;
    z-index: 20;
}

.status-bar {
    display: flex;
    justify-content: space-between;
    padding: 12px 20px 0;
    font-size: 13px;
    font-weight: 600;
    z-index: 10;
}

.status-icon {
    width: 16px;
    height: 10px;
}

.lock-screen-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    height: 100%;
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
}

.time-widget {
    margin-top: 3.5rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    z-index: 10;
}

.date {
    font-size: 1rem;
    font-weight: 500;
}

.clock {
    font-size: 4.5rem;
    font-weight: 600;
    line-height: 1;
    letter-spacing: -2px;
    margin-top: -5px;
}

.wallpaper-content {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1.5rem;
}

.verse-container {
    width: 100%;
    text-align: center;
}

.verse-text {
    font-family: var(--font-serif);
    font-size: 1.35rem;
    line-height: 1.3;
    font-weight: 400;
    font-style: italic;
    margin-bottom: 1.5rem;
}

.verse-ref {
    font-family: var(--font-sans);
    font-size: 0.7rem;
    font-weight: 600;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: var(--device-accent);
}

/* Customization Panel Setup */
.customization-section {
    background: var(--surface-color);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 2rem;
}

/* Testimonials Section */
.testimonials-section {
    padding: 1rem 0 3rem;
}

.testimonials-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.5rem;
    margin-top: 2rem;
}

@media (min-width: 768px) {
    .testimonials-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

.testimonial-card {
    background: var(--surface-color);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    transition: transform var(--transition-fast);
}

.testimonial-card:hover {
    transform: translateY(-2px);
}

.stars {
    color: #FBBF24;
    font-size: 1.1rem;
    letter-spacing: 2px;
}

.review-text {
    font-style: italic;
    font-size: 0.95rem;
    color: var(--text-primary);
    flex-grow: 1;
}

.reviewer-name {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.section-header {
    text-align: center;
    margin-bottom: 2rem;
}

.section-header h3 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 0.25rem;
}

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

.form-row {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1rem;
}

@media (min-width: 640px) {
    .form-row {
        grid-template-columns: 1fr 1fr;
        gap: 1.5rem;
    }
}

.color-pickers-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
    background: var(--bg-primary);
    padding: 1rem;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
}

.color-input-group label {
    display: block;
    font-size: 0.75rem;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
    font-weight: 500;
}

.color-widget {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

input[type="color"] {
    -webkit-appearance: none;
    -moz-appearance: none;
    appearance: none;
    border: none;
    width: 2.5rem;
    height: 2.5rem;
    border-radius: var(--radius-sm);
    cursor: pointer;
    padding: 0;
    background: none;
}

input[type="color"]::-webkit-color-swatch-wrapper {
    padding: 0;
}

input[type="color"]::-webkit-color-swatch {
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
}

.color-widget input[type="text"] {
    width: 100%;
    padding: 0.5rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-family: monospace;
    font-size: 0.875rem;
    color: var(--text-primary);
}

.checkout-btn {
    margin-top: 1rem;
    background: #000; /* Simulated Apple Pay/Stripe look */
}

/* -------------------------
 * View 2: Success Page
 * ------------------------- */
#view-success {
    background: var(--surface-color);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 2.5rem 2rem;
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.success-header {
    text-align: center;
}

.success-icon {
    width: 64px;
    height: 64px;
    background: #E8F5E9;
    color: #4CAF50;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1rem;
}

.success-header h2 {
    font-size: 1.75rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    margin-bottom: 0.5rem;
}

.success-header p {
    color: var(--text-secondary);
}

.url-delivery-box {
    background: var(--bg-primary);
    padding: 1.5rem;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
}

.url-delivery-box label {
    display: block;
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 0.75rem;
}

.url-delivery-box .url-hint {
    font-size: 0.8125rem;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

.url-delivery-box .url-hint code {
    background: var(--surface-color);
    padding: 0.125rem 0.375rem;
    border-radius: 4px;
    font-size: 0.75rem;
}

.url-bar {
    display: flex;
    gap: 0.5rem;
}

.url-input {
    flex: 1;
    min-width: 0;
    padding: 0.875rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-family: monospace;
    font-size: 0.875rem;
    color: var(--text-primary);
    background: var(--surface-color);
}

.installation-guide {
    margin-top: 1rem;
}

.installation-guide h3 {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 0.25rem;
}

.guide-desc {
    color: var(--text-secondary);
    font-size: 0.875rem;
    margin-bottom: 1.5rem;
}

/* Tabs UI */
.tabs-container {
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--bg-primary);
    overflow: hidden;
}

.tabs-header {
    display: flex;
    border-bottom: 1px solid var(--border-color);
    background: var(--surface-color);
}

.tab-btn {
    flex: 1;
    padding: 1rem;
    background: none;
    border: none;
    border-bottom: 2px solid transparent;
    font-family: inherit;
    font-weight: 600;
    font-size: 0.875rem;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all var(--transition-fast);
}

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

.tab-btn.active {
    color: var(--text-primary);
    border-bottom-color: var(--text-primary);
    background: var(--bg-primary);
}

.tab-content {
    display: none;
    padding: 1.5rem;
}

.tab-content.active {
    display: block;
    animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.step-list {
    list-style-position: outside;
    padding-left: 1.25rem;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.step-list li {
    font-size: 0.95rem;
    color: #444;
}

.step-list li strong {
    color: var(--text-primary);
}

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

.app-footer p {
    font-size: 0.75rem;
    color: var(--text-secondary);
}