/* ===========================
   Global Styles & Reset
   =========================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Light Theme Colors */
    --primary-color: #6366f1;
    --secondary-color: #8b5cf6;
    --accent-color: #ec4899;
    --bg-primary: #f8fafc;
    --bg-secondary: #ffffff;
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --border-color: #e2e8f0;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.15);
    --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-secondary: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    --gradient-hero: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
    --glass-bg: rgba(255, 255, 255, 0.7);
    --glass-border: rgba(255, 255, 255, 0.18);
}

[data-theme="dark"] {
    /* Dark Theme Colors */
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --text-primary: #f1f5f9;
    --text-secondary: #cbd5e1;
    --border-color: #334155;
    --glass-bg: rgba(30, 41, 59, 0.7);
    --glass-border: rgba(255, 255, 255, 0.1);
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ===========================
   Typography
   =========================== */
h1, h2, h3, h4, h5, h6 {
    font-family: 'Poppins', sans-serif;
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 1rem;
}

h1 { font-size: clamp(2rem, 5vw, 3.5rem); }
h2 { font-size: clamp(1.75rem, 4vw, 2.5rem); }
h3 { font-size: clamp(1.25rem, 3vw, 1.75rem); }

.gradient-text {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.section-title {
    font-size: clamp(1.75rem, 4vw, 2.5rem);
    margin-bottom: 1rem;
}

.section-subtitle {
    font-size: clamp(1rem, 2vw, 1.125rem);
    color: var(--text-secondary);
    margin-bottom: 3rem;
}

.section-subtitle-small {
    font-size: 1.125rem;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

/* ===========================
   Header & Navigation
   =========================== */
.header {
    position: sticky;
    top: 0;
    background: var(--glass-bg);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--glass-border);
    z-index: 1000;
    padding: 1rem 0;
}

.navbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 2rem;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-family: 'Poppins', sans-serif;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
}

.logo i {
    font-size: 1.75rem;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 2rem;
    margin: 0;
}

.nav-link {
    color: var(--text-primary);
    text-decoration: none;
    font-weight: 500;
    padding: 0.5rem 0;
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-primary);
    transition: width 0.3s ease;
}

.nav-link:hover::after {
    width: 100%;
}

.theme-toggle {
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    color: var(--text-primary);
    width: 40px;
    height: 40px;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.125rem;
    transition: transform 0.3s ease, background 0.3s ease;
}

.theme-toggle:hover {
    transform: scale(1.1);
    background: var(--primary-color);
    color: white;
}

.mobile-menu-toggle {
    display: none;
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    color: var(--text-primary);
    width: 40px;
    height: 40px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1.25rem;
}

/* ===========================
   Hero Section
   =========================== */
.hero {
    padding: 6rem 0;
    background: var(--gradient-hero);
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg width="60" height="60" xmlns="http://www.w3.org/2000/svg"><path d="M0 0h60v60H0z" fill="none"/><path d="M30 0v60M0 30h60" stroke="rgba(255,255,255,0.1)" stroke-width="1"/></svg>');
    opacity: 0.3;
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
    position: relative;
    z-index: 1;
}

.hero-content {
    color: white;
}

.hero-title {
    margin-bottom: 1.5rem;
    color: white;
}

.hero-subtitle {
    font-size: 1.125rem;
    margin-bottom: 2rem;
    opacity: 0.95;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.hero-image {
    display: flex;
    justify-content: center;
    align-items: center;
}

.qr-demo {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(20px);
    border: 2px solid rgba(255, 255, 255, 0.2);
    border-radius: 24px;
    padding: 3rem;
    animation: float 3s ease-in-out infinite;
}

.qr-placeholder {
    width: 250px;
    height: 250px;
    background: white;
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-xl);
}

.qr-placeholder i {
    font-size: 8rem;
    color: var(--primary-color);
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-20px); }
}

/* ===========================
   Buttons
   =========================== */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.875rem 1.75rem;
    border: none;
    border-radius: 12px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    text-decoration: none;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

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

.btn-primary {
    background: var(--gradient-primary);
    color: white;
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    box-shadow: var(--shadow-lg);
}

.btn-secondary {
    background: var(--glass-bg);
    color: var(--text-primary);
    border: 1px solid var(--glass-border);
    backdrop-filter: blur(16px);
}

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

.btn-icon {
    background: rgba(239, 68, 68, 0.1);
    color: #ef4444;
    border: none;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: background 0.2s ease;
}

.btn-icon:hover {
    background: #ef4444;
    color: white;
}

/* ===========================
   Features Section
   =========================== */
.features {
    padding: 6rem 0;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.feature-card {
    background: var(--glass-bg);
    backdrop-filter: blur(16px);
    border: 1px solid var(--glass-border);
    border-radius: 20px;
    padding: 2rem;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
}

.feature-icon {
    width: 64px;
    height: 64px;
    background: var(--gradient-primary);
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.75rem;
    color: white;
    margin-bottom: 1.5rem;
}

.feature-card h3 {
    margin-bottom: 0.75rem;
}

.feature-card p {
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ===========================
   Generator Section
   =========================== */
.generator {
    padding: 6rem 0;
    background: var(--bg-secondary);
}

.generator-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    margin-top: 3rem;
}

.glass-card {
    background: var(--glass-bg);
    backdrop-filter: blur(16px);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    padding: 2rem;
    box-shadow: var(--shadow-md);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.form-input,
.form-select,
.form-textarea {
    width: 100%;
    padding: 0.875rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: 12px;
    font-size: 1rem;
    background: var(--bg-secondary);
    color: var(--text-primary);
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.form-textarea {
    min-height: 100px;
    resize: vertical;
    font-family: inherit;
}

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

.form-input-color {
    width: 100%;
    height: 48px;
    padding: 0.25rem;
    border: 1px solid var(--border-color);
    border-radius: 12px;
    cursor: pointer;
    background: var(--bg-secondary);
}

.form-input-file {
    padding: 0.5rem;
    font-size: 0.9rem;
}

.checkbox-label {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    cursor: pointer;
    user-select: none;
}

.checkbox-label input[type="checkbox"] {
    width: 20px;
    height: 20px;
    cursor: pointer;
    accent-color: var(--primary-color);
}

.customization-section {
    margin-top: 2rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border-color);
}

.logo-preview {
    margin-top: 1rem;
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem;
    background: var(--bg-secondary);
    border-radius: 12px;
    border: 1px solid var(--border-color);
}

.logo-preview img {
    width: 64px;
    height: 64px;
    object-fit: contain;
    border-radius: 8px;
}

/* ===========================
   QR Preview
   =========================== */
.qr-preview {
    min-height: 350px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-secondary);
    border-radius: 16px;
    padding: 2rem;
    margin-bottom: 1.5rem;
}

.qr-placeholder-empty {
    text-align: center;
    color: var(--text-secondary);
}

.qr-placeholder-empty i {
    font-size: 4rem;
    margin-bottom: 1rem;
    opacity: 0.5;
}

.qr-placeholder-empty p {
    font-size: 1.125rem;
}

#qrcode {
    display: flex;
    justify-content: center;
    align-items: center;
}

#qrcode img,
#qrcode canvas {
    max-width: 100%;
    height: auto;
    border-radius: 12px;
}

.qr-actions {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
    gap: 0.75rem;
}

.qr-actions .btn {
    padding: 0.75rem 1rem;
    font-size: 0.9rem;
    justify-content: center;
}

/* ===========================
   History & Favorites
   =========================== */
.history-section,
.favorites-section {
    padding: 4rem 0;
}

.history-header,
.favorites-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
}

.history-grid,
.favorites-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 1.5rem;
}

.history-item,
.favorite-item {
    background: var(--glass-bg);
    backdrop-filter: blur(16px);
    border: 1px solid var(--glass-border);
    border-radius: 16px;
    padding: 1.5rem;
    cursor: pointer;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
    position: relative;
}

.history-item:hover,
.favorite-item:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.history-item img,
.favorite-item img {
    width: 100%;
    height: auto;
    border-radius: 8px;
    margin-bottom: 1rem;
}

.history-item-info,
.favorite-item-info {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.history-item-type,
.favorite-item-type {
    font-weight: 600;
    color: var(--primary-color);
    margin-bottom: 0.25rem;
}

.history-item-content,
.favorite-item-content {
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.delete-item {
    position: absolute;
    top: 0.5rem;
    right: 0.5rem;
    background: rgba(239, 68, 68, 0.9);
    color: white;
    border: none;
    width: 28px;
    height: 28px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    opacity: 0;
    transition: opacity 0.2s ease;
}

.history-item:hover .delete-item,
.favorite-item:hover .delete-item {
    opacity: 1;
}

.empty-state {
    text-align: center;
    padding: 3rem;
    color: var(--text-secondary);
}

.empty-state i {
    font-size: 3rem;
    margin-bottom: 1rem;
    opacity: 0.5;
}

/* ===========================
   FAQ Section
   =========================== */
.faq {
    padding: 6rem 0;
    background: var(--bg-secondary);
}

.faq-container {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    background: var(--glass-bg);
    backdrop-filter: blur(16px);
    border: 1px solid var(--glass-border);
    border-radius: 16px;
    margin-bottom: 1rem;
    overflow: hidden;
}

.faq-question {
    width: 100%;
    padding: 1.5rem;
    background: none;
    border: none;
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
    transition: background 0.2s ease;
}

.faq-question:hover {
    background: rgba(99, 102, 241, 0.05);
}

.faq-question i {
    transition: transform 0.3s ease;
}

.faq-item.active .faq-question i {
    transform: rotate(180deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease, padding 0.3s ease;
}

.faq-item.active .faq-answer {
    max-height: 500px;
    padding: 0 1.5rem 1.5rem;
}

.faq-answer p {
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ===========================
   Contact Section
   =========================== */
.contact {
    padding: 6rem 0;
}

.contact-info {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.contact-card {
    background: var(--glass-bg);
    backdrop-filter: blur(16px);
    border: 1px solid var(--glass-border);
    border-radius: 20px;
    padding: 2rem;
    text-align: center;
}

.contact-card i {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.contact-card h3 {
    margin-bottom: 0.5rem;
}

.contact-card p {
    color: var(--text-secondary);
}

/* ===========================
   Footer
   =========================== */
.footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    padding: 3rem 0 1.5rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-family: 'Poppins', sans-serif;
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.footer-section h4 {
    margin-bottom: 1rem;
    font-size: 1.125rem;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: color 0.2s ease;
}

.footer-section a:hover {
    color: var(--primary-color);
}

.social-links {
    display: flex;
    gap: 1rem;
}

.social-links a {
    width: 40px;
    height: 40px;
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.125rem;
    transition: background 0.2s ease, transform 0.2s ease;
}

.social-links a:hover {
    background: var(--gradient-primary);
    color: white;
    transform: scale(1.1);
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid var(--border-color);
    color: var(--text-secondary);
}

/* ===========================
   Modal
   =========================== */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.9);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 2000;
    padding: 2rem;
}

.modal-content {
    position: relative;
    max-width: 90%;
    max-height: 90%;
}

.modal-close {
    position: absolute;
    top: -40px;
    right: 0;
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    color: white;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-size: 1.25rem;
    transition: background 0.2s ease;
}

.modal-close:hover {
    background: rgba(255, 255, 255, 0.2);
}

/* ===========================
   Toast Notification
   =========================== */
.toast {
    position: fixed;
    top: 100px;
    right: 20px;
    background: var(--glass-bg);
    backdrop-filter: blur(16px);
    border: 1px solid var(--glass-border);
    border-radius: 12px;
    padding: 1rem 1.5rem;
    box-shadow: var(--shadow-lg);
    z-index: 3000;
    animation: slideIn 0.3s ease;
    max-width: 350px;
}

.toast.success {
    border-left: 4px solid #10b981;
}

.toast.error {
    border-left: 4px solid #ef4444;
}

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

/* ===========================
   Loading Overlay
   =========================== */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.7);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 4000;
}

.loader {
    width: 50px;
    height: 50px;
    border: 4px solid rgba(255, 255, 255, 0.2);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

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

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

/* ===========================
   Responsive Design
   =========================== */
@media (max-width: 968px) {
    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-buttons {
        justify-content: center;
    }
    
    .hero-image {
        order: -1;
    }
    
    .generator-wrapper {
        grid-template-columns: 1fr;
    }
    
    .nav-links {
        display: none;
    }
    
    .mobile-menu-toggle {
        display: flex;
    }
}

@media (max-width: 640px) {
    .container {
        padding: 0 16px;
    }
    
    .hero {
        padding: 4rem 0;
    }
    
    .features,
    .generator,
    .faq,
    .contact {
        padding: 3rem 0;
    }
    
    .history-section,
    .favorites-section {
        padding: 2rem 0;
    }
    
    .qr-demo {
        padding: 2rem;
    }
    
    .qr-placeholder {
        width: 180px;
        height: 180px;
    }
    
    .qr-placeholder i {
        font-size: 5rem;
    }
    
    .form-row {
        grid-template-columns: 1fr;
    }
    
    .qr-actions {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .history-grid,
    .favorites-grid {
        grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    }
    
    .glass-card {
        padding: 1.5rem;
    }
    
    .btn {
        padding: 0.75rem 1.5rem;
        font-size: 0.9rem;
    }
}

/* ===========================
   Accessibility
   =========================== */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

button:focus-visible,
a:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}