/* --- Variables & Reset --- */
:root {
    --bg-color: #f8fafc;
    --text-main: #1e293b;
    --text-muted: #64748b;
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --surface: #ffffff;
    --border: #e2e8f0;
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
    --max-width: 680px; /* Forces One-Column Readability */
}

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

body {
    font-family: 'Inter', -apple-system, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* --- Header & Navigation --- */
.site-header {
    background: var(--surface);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.logo {
    font-size: 1.25rem;
    font-weight: 900;
    color: var(--primary);
    text-decoration: none;
    letter-spacing: -0.5px;
}
.logo span { color: var(--text-main); }

.nav-menu {
    display: none;
    gap: 1.5rem;
}
.nav-menu a {
    text-decoration: none;
    color: var(--text-muted);
    font-weight: 600;
    font-size: 0.9rem;
    transition: color 0.2s;
}
.nav-menu a:hover, .nav-menu a.active { color: var(--primary); }

.menu-btn {
    display: block;
    background: none;
    border: none;
    width: 32px;
    height: 32px;
    cursor: pointer;
    color: var(--text-main);
}

@media (min-width: 768px) {
    .menu-btn { display: none; }
    .nav-menu { display: flex; }
}

/* Mobile Nav Active State */
.nav-menu.mobile-active {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 70px;
    left: 0;
    width: 100%;
    background: var(--surface);
    padding: 1.5rem;
    border-bottom: 1px solid var(--border);
    box-shadow: 0 10px 15px -3px rgba(0,0,0,0.05);
}

/* --- Main Layout & Hero --- */
.one-column-layout {
    display: flex;
    flex-direction: column;
    gap: 3rem;
    padding-top: 3rem;
    padding-bottom: 4rem;
}

.hero { text-align: center; }
.eyebrow {
    display: inline-block;
    background: #dbeafe;
    color: var(--primary-dark);
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 1rem;
}
h1 {
    font-size: 2.5rem;
    font-weight: 900;
    line-height: 1.1;
    margin-bottom: 1rem;
    letter-spacing: -1px;
}
.hero p { font-size: 1.1rem; color: var(--text-muted); }

/* --- Calculator Interface --- */
.calc-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 1.5rem;
    padding: 2rem;
    box-shadow: 0 20px 25px -5px rgba(0,0,0,0.05);
}

.input-group { margin-bottom: 1.5rem; }
label {
    display: block;
    font-size: 0.8rem;
    font-weight: 700;
    color: var(--text-muted);
    text-transform: uppercase;
    margin-bottom: 0.5rem;
}
select, input[type="number"] {
    width: 100%;
    padding: 1rem;
    border: 2px solid #f1f5f9;
    border-radius: 0.75rem;
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-main);
    background: var(--bg-color);
    transition: border-color 0.2s;
    outline: none;
}
select:focus, input[type="number"]:focus {
    border-color: var(--primary);
    background: var(--surface);
}

/* Range Slider Convenience */
.range-wrapper {
    display: flex;
    align-items: center;
    gap: 1rem;
    background: var(--bg-color);
    padding: 0.5rem 1rem;
    border-radius: 0.75rem;
    border: 2px solid #f1f5f9;
}
input[type="range"] { flex-grow: 1; cursor: pointer; }
output { font-weight: 700; color: var(--primary); min-width: 3.5rem; text-align: right; }

.highlight-input input { border-color: #bae6fd; background: #f0f9ff; color: var(--primary-dark); font-size: 1.25rem; }

/* Results Dashboard */
.results-dashboard {
    margin-top: 2rem;
    background: var(--text-main);
    border-radius: 1rem;
    padding: 2rem;
    color: white;
    text-align: center;
}
.results-label { font-size: 0.85rem; font-weight: 600; color: #94a3b8; text-transform: uppercase; letter-spacing: 0.5px; }
.results-value { font-size: 3.5rem; font-weight: 900; color: #60a5fa; margin: 0.5rem 0; line-height: 1; }

.risk-meter { margin-top: 1.5rem; text-align: left; }
.risk-labels { display: flex; justify-content: space-between; font-size: 0.85rem; font-weight: 700; margin-bottom: 0.5rem; }
.progress-bar { height: 8px; background: rgba(255,255,255,0.1); border-radius: 4px; overflow: hidden; }
.progress-fill { height: 100%; width: 0%; background: var(--success); transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1); }
.risk-disclaimer { font-size: 0.7rem; color: #fff; margin-top: 0.5rem; font-style: italic; text-align: center; }

/* --- SEO Article --- */
.seo-article { border-top: 1px solid var(--border); padding-top: 3rem; }
.seo-article h2 { font-size: 1.75rem; font-weight: 800; margin-bottom: 1rem; }
.seo-article h3 { font-size: 1.25rem; font-weight: 700; margin: 1.5rem 0 0.75rem; }
.seo-article p { margin-bottom: 1rem; }
.callout-box {
    background: #fffbeb;
    border-left: 4px solid var(--warning);
    padding: 1.25rem;
    border-radius: 0 0.5rem 0.5rem 0;
    margin: 1.5rem 0;
    font-size: 0.95rem;
}

/* --- Footer --- */
.site-footer {
    border-top: 1px solid var(--border);
    padding: 3rem 0;
    text-align: center;
    background: var(--surface);
}
.site-footer p { color: var(--text-main); font-weight: 700; margin-bottom: 0.5rem; }
.site-footer .disclaimer { font-size: 0.75rem; color: var(--text-muted); font-weight: 400; max-width: 500px; margin: 0 auto 1.5rem; }
.footer-links { display: flex; justify-content: center; gap: 1.5rem; }
.footer-links a { color: var(--primary); font-size: 0.85rem; text-decoration: none; font-weight: 600; }