/* Health & Fitness Calculator Styles */
:root {
    --primary: #10b981;
    --primary-dark: #059669;
    --primary-light: #d1fae5;
    --secondary: #3b82f6;
    --accent: #f59e0b;
    --bg: #f8fafc;
    --card: #ffffff;
    --text: #1e293b;
    --text-muted: #64748b;
    --border: #e2e8f0;
    --shadow: 0 4px 6px -1px rgba(0,0,0,0.1), 0 2px 4px -2px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -4px rgba(0,0,0,0.1);
    --radius: 16px;
    --radius-sm: 12px;
    --max-width: 1200px;
    --font-main: 'DM Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-display: 'Outfit', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body { font-family: var(--font-main); background: var(--bg); color: var(--text); line-height: 1.6; min-height: 100vh; }

/* Container */
.container { max-width: var(--max-width); margin: 0 auto; padding: 0 1.25rem; }

/* Header */
.header {
    background: rgba(255,255,255,0.95);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
}
.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 0;
    max-width: var(--max-width);
    margin: 0 auto;
    padding-left: 1.25rem;
    padding-right: 1.25rem;
}
.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    text-decoration: none;
    color: inherit;
}
.logo-icon {
    width: 44px;
    height: 44px;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
}
.logo-text {
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 1.25rem;
    color: var(--text);
}
.logo-text span { color: var(--primary); }
.main-nav { display: flex; align-items: center; gap: 1.5rem; }
.nav-link {
    color: var(--text-muted);
    text-decoration: none;
    font-weight: 500;
    font-size: 0.95rem;
    transition: color 0.2s;
}
.nav-link:hover { color: var(--primary); }

/* Breadcrumb */
.breadcrumb {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.875rem;
    color: var(--text-muted);
    padding: 1.25rem 0;
}
.breadcrumb a { color: var(--primary); text-decoration: none; }
.breadcrumb a:hover { text-decoration: underline; }
.breadcrumb svg { width: 14px; height: 14px; }

/* Calculator Page */
.calculator-page { padding-bottom: 3rem; }
.calculator-container {
    display: grid;
    grid-template-columns: 1.2fr 0.8fr;
    gap: 1.5rem;
    margin-bottom: 2rem;
}
@media (max-width: 900px) { .calculator-container { grid-template-columns: 1fr; } }

/* Calculator Main */
.calculator-main {
    background: var(--card);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
    padding: 1.75rem;
}
.calculator-title {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    margin-bottom: 1.5rem;
    padding-bottom: 1.25rem;
    border-bottom: 1px solid var(--border);
}
.calculator-title-icon {
    width: 52px;
    height: 52px;
    background: linear-gradient(135deg, var(--primary-light), #dbeafe);
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.75rem;
    flex-shrink: 0;
}
.calculator-title h1 {
    font-family: var(--font-display);
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--text);
    line-height: 1.2;
}

/* Form */
.calc-form { display: flex; flex-direction: column; gap: 1rem; }
.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
}
@media (max-width: 600px) { .form-row { grid-template-columns: 1fr; } }
.form-group { display: flex; flex-direction: column; gap: 0.375rem; }
.form-group label {
    font-weight: 600;
    font-size: 0.875rem;
    color: var(--text);
}
.input-wrapper {
    position: relative;
    display: flex;
    align-items: center;
}
.input-wrapper input, .input-wrapper select {
    width: 100%;
    padding: 0.875rem 1rem;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    font-size: 1rem;
    font-family: inherit;
    color: var(--text);
    background: var(--card);
    transition: border-color 0.2s, box-shadow 0.2s;
}
.input-wrapper input:focus, .input-wrapper select:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-light);
}
.input-wrapper .unit {
    position: absolute;
    right: 1rem;
    color: var(--text-muted);
    font-size: 0.875rem;
    font-weight: 500;
    pointer-events: none;
}
.input-wrapper input[type="number"] { padding-right: 3rem; }

/* Buttons */
.btn-calculate, .btn-reset {
    padding: 0.875rem 1.5rem;
    border-radius: var(--radius-sm);
    font-size: 1rem;
    font-weight: 600;
    font-family: inherit;
    cursor: pointer;
    transition: all 0.2s;
    border: none;
}
.btn-calculate {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: white;
    flex: 1;
}
.btn-calculate:hover { transform: translateY(-2px); box-shadow: var(--shadow-lg); }
.btn-reset {
    background: var(--bg);
    color: var(--text-muted);
    border: 1px solid var(--border);
}
.btn-reset:hover { background: var(--border); }

/* Result Section */
.result-section { margin-top: 1.5rem; padding-top: 1.5rem; border-top: 1px solid var(--border); }
.result-box {
    background: linear-gradient(135deg, var(--primary-light), #dbeafe);
    border-radius: var(--radius-sm);
    padding: 1.25rem;
    text-align: center;
}
.result-label {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 0.5rem;
}
.result-value {
    font-family: var(--font-display);
    font-size: 2.25rem;
    font-weight: 800;
    color: var(--primary-dark);
}
.result-value .result-unit { font-size: 1.25rem; font-weight: 600; }
.result-formula {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-top: 0.5rem;
}
.result-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 0.75rem;
    margin-top: 1rem;
}
.result-item {
    background: rgba(255,255,255,0.7);
    border-radius: var(--radius-sm);
    padding: 0.875rem;
    text-align: center;
}
.result-item .label {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    margin-bottom: 0.25rem;
}
.result-item .value {
    font-family: var(--font-display);
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text);
}

/* Info Panel */
.info-panel { display: flex; flex-direction: column; gap: 1rem; }
.info-card {
    background: var(--card);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
    padding: 1.25rem;
}
.info-card h3 {
    font-family: var(--font-display);
    font-size: 1rem;
    font-weight: 700;
    color: var(--text);
    margin-bottom: 0.75rem;
    padding-bottom: 0.5rem;
    border-bottom: 1px solid var(--border);
}
.info-card p { font-size: 0.875rem; color: var(--text-muted); line-height: 1.6; }

/* Formula Display */
.formula-display {
    background: var(--bg);
    border-radius: var(--radius-sm);
    padding: 0.875rem;
    font-family: var(--font-mono);
    font-size: 0.875rem;
}
.formula-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.5rem 0;
}
.formula-item:not(:last-child) { border-bottom: 1px dashed var(--border); }
.formula-type {
    background: var(--primary);
    color: white;
    font-size: 0.7rem;
    font-weight: 700;
    padding: 0.25rem 0.5rem;
    border-radius: 6px;
    min-width: 40px;
    text-align: center;
}
.formula-text { color: var(--text); }

/* Quick Reference Table */
.quick-ref-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.8rem;
}
.quick-ref-table th, .quick-ref-table td {
    padding: 0.5rem;
    text-align: left;
    border-bottom: 1px solid var(--border);
}
.quick-ref-table th {
    font-weight: 600;
    color: var(--text-muted);
    font-size: 0.75rem;
    text-transform: uppercase;
}
.quick-ref-table tr:last-child td { border-bottom: none; }

/* Related Calculators */
.related-calcs { display: flex; flex-direction: column; gap: 0.5rem; }
.related-calc-link {
    display: block;
    padding: 0.625rem 0.875rem;
    background: var(--bg);
    border-radius: var(--radius-sm);
    color: var(--text);
    text-decoration: none;
    font-size: 0.875rem;
    font-weight: 500;
    transition: all 0.2s;
    border: 1px solid transparent;
}
.related-calc-link:hover {
    background: var(--primary-light);
    color: var(--primary-dark);
    border-color: var(--primary);
}

/* Content Section */
.content-section {
    background: var(--card);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
    padding: 2rem;
    margin-bottom: 1.5rem;
}
.content-section h2 {
    font-family: var(--font-display);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text);
    margin-bottom: 1rem;
}
.content-section h3 {
    font-family: var(--font-display);
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text);
    margin: 1.5rem 0 0.75rem;
}
.content-section p {
    color: var(--text-muted);
    line-height: 1.7;
    margin-bottom: 1rem;
}
.content-section ul, .content-section ol {
    color: var(--text-muted);
    padding-left: 1.5rem;
    margin-bottom: 1rem;
}
.content-section li { margin-bottom: 0.5rem; line-height: 1.6; }

/* FAQ Section */
.faq-section {
    background: var(--card);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
    padding: 2rem;
    margin-bottom: 1.5rem;
}
.faq-title {
    font-family: var(--font-display);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text);
    margin-bottom: 1.5rem;
    text-align: center;
}
.faq-grid { display: flex; flex-direction: column; gap: 0.75rem; }
.faq-item {
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    overflow: hidden;
    transition: all 0.2s;
}
.faq-item:hover { border-color: var(--primary); }
.faq-item.active { border-color: var(--primary); background: var(--primary-light); }
.faq-question {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 1.25rem;
    background: none;
    border: none;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 600;
    color: var(--text);
    text-align: left;
    font-family: inherit;
}
.faq-question svg { flex-shrink: 0; transition: transform 0.2s; }
.faq-item.active .faq-question svg { transform: rotate(180deg); }
.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
}
.faq-item.active .faq-answer { max-height: 500px; }
.faq-answer p {
    padding: 0 1.25rem 1rem;
    color: var(--text-muted);
    line-height: 1.7;
}

/* Footer */
.footer {
    background: var(--text);
    color: rgba(255,255,255,0.7);
    padding: 2.5rem 0;
    margin-top: auto;
}
.footer-bottom {
    text-align: center;
    font-size: 0.875rem;
}
.footer a { color: var(--primary-light); text-decoration: none; }
.footer a:hover { text-decoration: underline; }

/* Home Page Grid */
.calc-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.25rem;
    padding: 2rem 0;
}
.calc-card {
    background: var(--card);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
    padding: 1.5rem;
    text-decoration: none;
    color: inherit;
    transition: all 0.2s;
}
.calc-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary);
}
.calc-card-icon {
    width: 48px;
    height: 48px;
    background: linear-gradient(135deg, var(--primary-light), #dbeafe);
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    margin-bottom: 1rem;
}
.calc-card h3 {
    font-family: var(--font-display);
    font-size: 1.125rem;
    font-weight: 700;
    color: var(--text);
    margin-bottom: 0.5rem;
}
.calc-card p {
    font-size: 0.875rem;
    color: var(--text-muted);
    line-height: 1.5;
}

/* Category Section */
.category-section { margin-bottom: 2.5rem; }
.category-title {
    font-family: var(--font-display);
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text);
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--primary);
    display: inline-block;
}

/* Hero Section */
.hero {
    text-align: center;
    padding: 3rem 0 2rem;
}
.hero h1 {
    font-family: var(--font-display);
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--text);
    margin-bottom: 1rem;
}
.hero p {
    font-size: 1.125rem;
    color: var(--text-muted);
    max-width: 600px;
    margin: 0 auto;
}

/* Responsive */
@media (max-width: 768px) {
    .header-inner { flex-wrap: wrap; }
    .main-nav { display: none; }
    .hero h1 { font-size: 1.75rem; }
    .calculator-title h1 { font-size: 1.375rem; }
    .result-value { font-size: 1.75rem; }
}