/* EZ Virtual Tools - HVAC Calculator Suite */
/* Dark theme with blue accent (#3b82f6) */

:root {
    --bg-primary: #0a0a0f;
    --bg-secondary: #12121a;
    --bg-card: #1a1a24;
    --accent: #3b82f6;
    --accent-hover: #2563eb;
    --accent-glow: rgba(59, 130, 246, 0.15);
    --text-primary: #f0f0f5;
    --text-secondary: #a0a0b0;
    --text-muted: #6b6b7b;
    --border: #2a2a35;
    --border-light: #3a3a45;
    --success: #10b981;
    --warning: #f59e0b;
    --error: #ef4444;
    --info: #06b6d4;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif; background: var(--bg-primary); color: var(--text-primary); line-height: 1.6; min-height: 100vh; }

h1, h2, h3, h4, h5, h6 { font-weight: 600; line-height: 1.3; }
h1 { font-size: 2rem; } h2 { font-size: 1.5rem; } h3 { font-size: 1.25rem; }
a { color: var(--accent); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--accent-hover); }

.container { max-width: 1400px; margin: 0 auto; padding: 0 1.5rem; }
.page-container { padding: 2rem 0 4rem; }

.nav { background: var(--bg-secondary); border-bottom: 1px solid var(--border); position: sticky; top: 0; z-index: 100; }
.nav-inner { display: flex; align-items: center; justify-content: space-between; padding: 0.75rem 1.5rem; max-width: 1400px; margin: 0 auto; }
.nav-brand { display: flex; align-items: center; gap: 0.5rem; font-weight: 700; font-size: 1.125rem; color: var(--text-primary); }
.nav-brand span { color: var(--accent); }
.nav-links { display: flex; align-items: center; gap: 0.25rem; }
.nav-link { padding: 0.5rem 1rem; border-radius: 0.5rem; color: var(--text-secondary); font-size: 0.875rem; font-weight: 500; transition: all 0.2s; }
.nav-link:hover { color: var(--text-primary); background: var(--bg-card); }
.nav-link.active { color: var(--accent); background: var(--accent-glow); }
.nav-toggle { display: none; background: none; border: none; color: var(--text-primary); font-size: 1.5rem; cursor: pointer; }

@media (max-width: 768px) {
    .nav-toggle { display: block; }
    .nav-links { display: none; position: absolute; top: 100%; left: 0; right: 0; background: var(--bg-secondary); border-bottom: 1px solid var(--border); flex-direction: column; padding: 1rem; }
    .nav-links.open { display: flex; }
}

.card { background: var(--bg-card); border: 1px solid var(--border); border-radius: 0.75rem; padding: 1.5rem; }
.card-header { margin-bottom: 1.5rem; }
.card-title { font-size: 1.25rem; margin-bottom: 0.5rem; }
.card-description { color: var(--text-secondary); font-size: 0.875rem; }

.grid { display: grid; gap: 1.5rem; }
.grid-2 { grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); }
.grid-3 { grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); }
.grid-4 { grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); }

.calc-card { display: block; background: var(--bg-card); border: 1px solid var(--border); border-radius: 0.75rem; padding: 1.5rem; transition: all 0.2s; }
.calc-card:hover { border-color: var(--accent); transform: translateY(-2px); box-shadow: 0 4px 20px var(--accent-glow); }
.calc-card h3 { color: var(--accent); margin-bottom: 0.5rem; }
.calc-card p { color: var(--text-secondary); font-size: 0.875rem; }

.form-group { margin-bottom: 1.25rem; }
.form-label { display: block; font-size: 0.875rem; font-weight: 500; margin-bottom: 0.5rem; color: var(--text-secondary); }
.form-input, .form-select { width: 100%; padding: 0.75rem 1rem; background: var(--bg-secondary); border: 1px solid var(--border); border-radius: 0.5rem; color: var(--text-primary); font-size: 1rem; transition: border-color 0.2s, box-shadow 0.2s; }
.form-input:focus, .form-select:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-glow); }
.form-row { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 1rem; }
.input-group { display: flex; }
.input-group .form-input { border-radius: 0.5rem 0 0 0.5rem; border-right: none; }
.input-group-text { display: flex; align-items: center; padding: 0 1rem; background: var(--bg-primary); border: 1px solid var(--border); border-radius: 0 0.5rem 0.5rem 0; color: var(--text-secondary); font-size: 0.875rem; }

.btn { display: inline-flex; align-items: center; justify-content: center; gap: 0.5rem; padding: 0.75rem 1.5rem; font-size: 1rem; font-weight: 600; border-radius: 0.5rem; border: none; cursor: pointer; transition: all 0.2s; }
.btn-primary { background: var(--accent); color: white; }
.btn-primary:hover { background: var(--accent-hover); }
.btn-secondary { background: var(--bg-secondary); color: var(--text-primary); border: 1px solid var(--border); }
.btn-block { width: 100%; }
.btn-lg { padding: 1rem 2rem; font-size: 1.125rem; }

.result-box { background: var(--bg-secondary); border: 1px solid var(--border); border-radius: 0.75rem; padding: 1.5rem; margin-top: 1.5rem; }
.result-row { display: flex; justify-content: space-between; align-items: center; padding: 0.75rem 0; border-bottom: 1px solid var(--border); }
.result-row:last-child { border-bottom: none; }
.result-label { color: var(--text-secondary); font-size: 0.875rem; }
.result-value { font-size: 1.125rem; font-weight: 600; color: var(--accent); }
.result-highlight { background: var(--accent-glow); border-color: var(--accent); text-align: center; }
.result-highlight .result-value { font-size: 2rem; }

.table-container { overflow-x: auto; border-radius: 0.75rem; border: 1px solid var(--border); }
table { width: 100%; border-collapse: collapse; font-size: 0.875rem; }
th, td { padding: 0.75rem 1rem; text-align: left; border-bottom: 1px solid var(--border); }
th { background: var(--bg-secondary); font-weight: 600; color: var(--text-secondary); text-transform: uppercase; font-size: 0.75rem; }
td.highlight { color: var(--accent); font-weight: 600; }

.tabs { display: flex; gap: 0.25rem; border-bottom: 1px solid var(--border); margin-bottom: 1.5rem; }
.tab { padding: 0.75rem 1.25rem; background: none; border: none; color: var(--text-secondary); font-size: 0.875rem; font-weight: 500; cursor: pointer; border-bottom: 2px solid transparent; transition: all 0.2s; }
.tab:hover { color: var(--text-primary); }
.tab.active { color: var(--accent); border-bottom-color: var(--accent); }
.tab-content { display: none; }
.tab-content.active { display: block; }

.hero { text-align: center; padding: 3rem 0; border-bottom: 1px solid var(--border); }
.hero h1 { font-size: 2.5rem; margin-bottom: 1rem; }
.hero h1 span { color: var(--accent); }
.hero p { color: var(--text-secondary); font-size: 1.125rem; max-width: 600px; margin: 0 auto; }
.hero-stats { display: flex; justify-content: center; gap: 3rem; margin-top: 2rem; }
.hero-stat-value { font-size: 2rem; font-weight: 700; color: var(--accent); }
.hero-stat-label { font-size: 0.875rem; color: var(--text-secondary); }

.section { padding: 3rem 0; }
.section-header { margin-bottom: 2rem; }
.section-title { font-size: 1.5rem; margin-bottom: 0.5rem; }
.section-description { color: var(--text-secondary); }

.breadcrumb { display: flex; align-items: center; gap: 0.5rem; font-size: 0.875rem; color: var(--text-secondary); margin-bottom: 1.5rem; }
.breadcrumb a { color: var(--text-secondary); }
.breadcrumb a:hover { color: var(--accent); }

.alert { padding: 1rem 1.25rem; border-radius: 0.5rem; margin-bottom: 1rem; font-size: 0.875rem; }
.alert-info { background: rgba(59, 130, 246, 0.1); border: 1px solid rgba(59, 130, 246, 0.2); color: var(--accent); }
.alert-warning { background: rgba(245, 158, 11, 0.1); border: 1px solid rgba(245, 158, 11, 0.2); color: var(--warning); }
.alert-success { background: rgba(16, 185, 129, 0.1); border: 1px solid rgba(16, 185, 129, 0.2); color: var(--success); }

.footer { background: var(--bg-secondary); border-top: 1px solid var(--border); padding: 2rem; text-align: center; color: var(--text-secondary); font-size: 0.875rem; }
.footer a { color: var(--accent); }

.text-center { text-align: center; }
.text-muted { color: var(--text-secondary); }
.text-accent { color: var(--accent); }
.text-success { color: var(--success); }
.text-warning { color: var(--warning); }
.mt-1 { margin-top: 0.5rem; } .mt-2 { margin-top: 1rem; } .mt-3 { margin-top: 1.5rem; } .mt-4 { margin-top: 2rem; }
.mb-1 { margin-bottom: 0.5rem; } .mb-2 { margin-bottom: 1rem; } .mb-3 { margin-bottom: 1.5rem; }

/* ============================================================
   UNIFIED FOOTER STYLES
   ============================================================ */
.footer {
    background: var(--bg-secondary, #12121a);
    border-top: 1px solid var(--border, #2a2a35);
    padding: 2rem 1rem;
    margin-top: 3rem;
}

.footer-inner {
    max-width: 1200px;
    margin: 0 auto;
    text-align: center;
}

.footer-brand {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: var(--text-primary, #f0f0f5);
}

.footer-brand span {
    color: var(--accent, #3b82f6);
}

.footer-links {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.5rem 1rem;
    margin-bottom: 1.5rem;
}

.footer-link {
    color: var(--text-secondary, #a0a0b0);
    text-decoration: none;
    font-size: 0.875rem;
    padding: 0.25rem 0.5rem;
    border-radius: 4px;
    transition: all 0.2s;
}

.footer-link:hover {
    color: var(--accent, #3b82f6);
    background: rgba(59, 130, 246, 0.1);
}

.footer-link.active {
    color: var(--accent, #3b82f6);
    font-weight: 500;
}

.footer-copy {
    color: var(--text-muted, #6b6b7b);
    font-size: 0.8rem;
}

.footer-copy a {
    color: var(--accent, #3b82f6);
    text-decoration: none;
}

.footer-disclaimer {
    max-width: 800px;
    margin: 0 auto 1.5rem;
    padding: 1rem;
    background: rgba(245, 158, 11, 0.1);
    border: 1px solid rgba(245, 158, 11, 0.3);
    border-radius: 8px;
    font-size: 0.8rem;
    color: var(--text-secondary, #a0a0b0);
}