:root {
    --bg-dark: #0f172a;
    --card-bg: #1e293b;
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --accent: #3b82f6;
    --accent-hover: #2563eb;
    --success: #10b981;
    --danger: #ef4444;
    --border-color: #334155;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: 'Segoe UI', system-ui, sans-serif;
}

body {
    background-color: var(--bg-dark);
    color: var(--text-main);
    line-height: 1.6;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

.main-wrapper {
    flex: 1;
    max-width: 1100px;
    margin: 0 auto;
    padding: 40px 20px;
    width: 100%;
}

.top-header {
    text-align: center;
    margin-bottom: 40px;
}

.top-header h1 {
    font-size: 2.8rem;
    background: linear-gradient(to right, #60a5fa, #3b82f6);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 10px;
}

.top-header p {
    color: var(--text-muted);
    font-size: 1.1rem;
}

/* App Container */
.app-container {
    display: flex;
    background: var(--card-bg);
    border-radius: 16px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
    overflow: hidden;
    margin-bottom: 50px;
    border: 1px solid var(--border-color);
}

.input-section {
    flex: 1;
    padding: 40px;
    border-right: 1px solid var(--border-color);
}

.output-section {
    flex: 1;
    padding: 40px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: #151e2e;
}

/* Tabs */
.tabs {
    display: flex;
    gap: 10px;
    margin-bottom: 25px;
    background: var(--bg-dark);
    padding: 5px;
    border-radius: 8px;
}

.tab-btn {
    flex: 1;
    padding: 12px;
    border: none;
    background: transparent;
    color: var(--text-muted);
    font-weight: 600;
    cursor: pointer;
    border-radius: 6px;
    transition: all 0.3s;
}

.tab-btn.active, .tab-btn:hover {
    background: var(--card-bg);
    color: var(--accent);
    box-shadow: 0 2px 5px rgba(0,0,0,0.2);
}

.tab-content {
    display: none;
    flex-direction: column;
    gap: 15px;
}

.tab-content.active {
    display: flex;
}

label {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-main);
    margin-bottom: -5px;
}

input, select {
    padding: 14px;
    background: var(--bg-dark);
    border: 1px solid var(--border-color);
    color: var(--text-main);
    border-radius: 8px;
    font-size: 1rem;
    outline: none;
    transition: 0.3s;
}

input:focus, select:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 2px rgba(59, 130, 246, 0.2);
}

.error-msg {
    display: none;
    color: var(--danger);
    font-size: 13px;
    margin-top: -10px;
}

.generate-btn {
    margin-top: 25px;
    width: 100%;
    padding: 16px;
    background: var(--accent);
    color: #fff;
    border: none;
    border-radius: 8px;
    font-size: 1.1rem;
    font-weight: bold;
    cursor: pointer;
    transition: background 0.3s;
}

.generate-btn:hover {
    background: var(--accent-hover);
}

/* QR Output */
#qrcode-display {
    width: 280px;
    height: 280px;
    background: #fff;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 15px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.3);
}

.placeholder-text {
    color: #64748b;
    text-align: center;
    font-size: 0.9rem;
}

.download-btn {
    margin-top: 30px;
    padding: 14px 30px;
    background: var(--success);
    color: #fff;
    border: none;
    border-radius: 8px;
    font-weight: bold;
    font-size: 1rem;
    cursor: pointer;
    display: none;
    transition: 0.3s;
}

.download-btn:hover {
    background: #059669;
}

/* SEO Content Section */
.seo-content {
    background: var(--card-bg);
    padding: 40px;
    border-radius: 16px;
    border: 1px solid var(--border-color);
    color: #cbd5e1;
}

.seo-content h2 {
    color: var(--text-main);
    margin-top: 30px;
    margin-bottom: 15px;
    font-size: 1.8rem;
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 10px;
}

.seo-content h2:first-child {
    margin-top: 0;
}

.seo-content h3 {
    color: var(--text-main);
    margin-top: 25px;
    margin-bottom: 10px;
}

.seo-content h4 {
    color: var(--text-main);
    margin-top: 20px;
    margin-bottom: 8px;
}

.seo-content p {
    margin-bottom: 15px;
}

.seo-content ul {
    margin-left: 20px;
    margin-bottom: 20px;
}

.seo-content li {
    margin-bottom: 8px;
}

.faq-container {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.faq-item h4 {
    color: var(--accent);
    margin-bottom: 5px;
}

/* Footer */
footer {
    background: #020617;
    padding: 40px 20px;
    text-align: center;
    border-top: 1px solid var(--border-color);
}

.footer-links {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 25px;
    margin-bottom: 20px;
}

.footer-links a {
    color: var(--text-muted);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
}

.footer-links a:hover {
    color: var(--accent);
}

.footer-bottom p {
    color: #64748b;
    font-size: 0.9rem;
    margin-bottom: 5px;
}

.footer-bottom a {
    color: var(--accent);
    text-decoration: none;
}

@media (max-width: 768px) {
    .app-container { flex-direction: column; }
    .input-section { border-right: none; border-bottom: 1px solid var(--border-color); padding: 25px; }
    .output-section { padding: 25px; }
    .seo-content { padding: 25px; }
}