:root {
    --primary-color: #2b6cb0;
    --primary-hover: #2c5282;
    --secondary-color: #ecc94b;
    --bg-color: #ffffff;
    --bg-light: #f7fafc;
    --text-main: #2d3748;
    --text-muted: #718096;
    --border-color: #e2e8f0;
    --error-color: #c53030;
    --radius: 8px;
    --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
}

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

body {
    font-family: var(--font-sans);
    color: var(--text-main);
    line-height: 1.6;
    background-color: var(--bg-color);
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

.bg-light {
    background-color: var(--bg-light);
}

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

.mb-2 {
    margin-bottom: 1rem;
}

/* Header */
.site-header {
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
}

.nav-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 700;
    font-size: 1.25rem;
    color: var(--primary-color);
}

nav a {
    margin-left: 1.5rem;
    text-decoration: none;
    color: var(--text-main);
    font-weight: 500;
    transition: color 0.2s;
}

nav a:hover {
    color: var(--primary-color);
}

/* Hero */
.hero {
    padding: 4rem 0;
    border-bottom: 1px solid var(--border-color);
}

.hero h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    color: var(--text-main);
}

.hero p {
    font-size: 1.125rem;
    color: var(--text-muted);
    max-width: 700px;
    margin: 0 auto;
}

/* Calculator Section */
.calculator-section {
    padding: 4rem 0;
}

.calc-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}

.card {
    background: var(--bg-color);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    padding: 2rem;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
}

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

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
}

.form-group input, .form-group select {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    font-size: 1rem;
    font-family: inherit;
}

.form-group input:focus, .form-group select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(43, 108, 176, 0.2);
}

.btn {
    display: inline-block;
    width: 100%;
    padding: 0.75rem 1.5rem;
    background-color: var(--primary-color);
    color: #fff;
    border: none;
    border-radius: var(--radius);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.2s;
}

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

/* Results */
.results-empty {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
    color: var(--text-muted);
    text-align: center;
    gap: 1rem;
}

.hidden {
    display: none !important;
}

.primary-result {
    text-align: center;
    padding: 2rem 0;
    border-bottom: 1px solid var(--border-color);
    margin-bottom: 1.5rem;
}

.lumen-value {
    display: block;
    font-size: 3.5rem;
    font-weight: 800;
    color: var(--primary-color);
    line-height: 1;
}

.lumen-label {
    font-size: 1.125rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 1px;
    font-weight: 600;
}

.result-details p {
    background: var(--bg-light);
    padding: 0.75rem;
    border-radius: var(--radius);
    margin-bottom: 0.5rem;
    display: flex;
    justify-content: space-between;
}

.bulb-suggestions {
    margin-top: 1.5rem;
}

.bulb-suggestions h4 {
    margin-bottom: 0.75rem;
}

.bulb-suggestions ul {
    list-style: none;
}

.bulb-suggestions li {
    position: relative;
    padding-left: 1.5rem;
    margin-bottom: 0.5rem;
}

.bulb-suggestions li::before {
    content: "•";
    color: var(--secondary-color);
    font-weight: bold;
    font-size: 1.5rem;
    position: absolute;
    left: 0;
    top: -5px;
}

.note {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-top: 1rem;
    font-style: italic;
}

/* Guide Section */
.guide-section {
    padding: 4rem 0;
    border-top: 1px solid var(--border-color);
}

.article-content {
    max-width: 760px;
    margin: 0 auto;
}

.article-content h2 {
    font-size: 2rem;
    margin-bottom: 1.5rem;
}

.article-content h3 {
    font-size: 1.5rem;
    margin-top: 2rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.article-content p {
    margin-bottom: 1.25rem;
}

.article-content ul {
    margin-bottom: 1.25rem;
    padding-left: 1.5rem;
}

.article-content li {
    margin-bottom: 0.5rem;
}

/* Footer */
.site-footer {
    text-align: center;
    padding: 2rem 0;
    border-top: 1px solid var(--border-color);
    color: var(--text-muted);
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    margin-bottom: 1rem;
}

.footer-links a {
    color: var(--text-muted);
    text-decoration: none;
}

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

/* Responsive */
@media (max-width: 768px) {
    .calc-grid {
        grid-template-columns: 1fr;
    }
    .hero h1 {
        font-size: 2rem;
    }
}


/* Factory-injected deployment helpers. The AI owns the site design above this block. */
.ad-unit {
  width: min(100%, 720px);
  min-height: 120px;
  margin: 24px auto;
  display: block;
}

.legal-page {
  width: min(900px, calc(100% - 32px));
  margin: 40px auto;
}

.factory-fallback-nav {
  width: min(900px, calc(100% - 32px));
  margin: 24px auto 0;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 16px;
  align-items: center;
  font-size: 0.95rem;
}

.factory-fallback-nav a {
  color: inherit;
  text-decoration: none;
  border-bottom: 1px solid currentColor;
}