/* Heart Rate Zone Calculator - Red/Rose Theme */
.hrzone-calculator-container { max-width: 900px; margin: 0 auto; font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif; color: #1e293b; line-height: 1.6; }
.hrzone-hero { background: linear-gradient(135deg, #ef4444, #dc2626); color: #fff; text-align: center; padding: 48px 32px; border-radius: 16px; margin-bottom: 32px; }
.hrzone-hero h1 { font-size: 2.2rem; margin: 0 0 8px; }
.hero-subtitle { font-size: 1.15rem; opacity: 0.9; margin: 0 0 20px; }
.hero-badges { display: flex; justify-content: center; gap: 12px; flex-wrap: wrap; }
.badge { background: rgba(255,255,255,0.18); padding: 6px 14px; border-radius: 20px; font-size: 0.85rem; display: flex; align-items: center; gap: 6px; }
.badge-icon { font-size: 1rem; }
.hrzone-stats { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; margin-bottom: 28px; }
.stat-item { background: #fef2f2; border: 1px solid #fecaca; border-radius: 12px; padding: 20px 16px; text-align: center; }
.stat-number { display: block; font-size: 1.8rem; font-weight: 800; color: #dc2626; }
.stat-label { font-size: 0.82rem; color: #64748b; margin-top: 4px; display: block; }
.privacy-notice { display: flex; align-items: center; gap: 12px; background: #f0fdf4; border: 1px solid #bbf7d0; border-radius: 10px; padding: 14px 18px; margin-bottom: 28px; }
.privacy-icon { font-size: 1.6rem; }
.privacy-notice strong { display: block; color: #166534; font-size: 0.95rem; }
.privacy-notice p { margin: 2px 0 0; font-size: 0.85rem; color: #4b5563; }
.calculator-form-section { background: #fff; border: 1px solid #e2e8f0; border-radius: 14px; padding: 32px; margin-bottom: 28px; box-shadow: 0 2px 12px rgba(0,0,0,0.06); }
.calculator-form-section h2 { color: #dc2626; font-size: 1.4rem; margin: 0 0 6px; }
.form-instructions { color: #64748b; margin: 0 0 24px; }
.field-row { display: flex; gap: 16px; margin-bottom: 16px; }
.field-row .field-group { flex: 1; }
.field-group { margin-bottom: 16px; }
.field-group label { display: block; font-weight: 600; font-size: 0.95rem; margin-bottom: 6px; color: #374151; }
.field-group input { width: 100%; padding: 12px 14px; border: 2px solid #e2e8f0; border-radius: 10px; font-size: 1rem; box-sizing: border-box; transition: border-color 0.2s; }
.field-group input:focus { border-color: #ef4444; outline: none; box-shadow: 0 0 0 3px rgba(239,68,68,0.15); }
.input-hint { display: block; font-size: 0.78rem; color: #94a3b8; margin-top: 4px; }
.form-submit { text-align: center; margin-top: 24px; }
.submit-btn { background: linear-gradient(135deg, #ef4444, #dc2626); color: #fff; border: none; padding: 14px 48px; font-size: 1.1rem; font-weight: 700; border-radius: 10px; cursor: pointer; transition: transform 0.2s, box-shadow 0.2s; }
.submit-btn:hover { transform: translateY(-2px); box-shadow: 0 6px 20px rgba(239,68,68,0.35); }
.results-section { background: #fff; border: 2px solid #fecaca; border-radius: 14px; padding: 32px; margin-bottom: 28px; text-align: center; }
.results-section h2 { color: #dc2626; }
.results-section h3 { color: #dc2626; text-align: left; }
.max-hr-display { margin: 20px 0 28px; }
.max-hr-label { display: block; font-size: 0.88rem; color: #64748b; font-weight: 600; text-transform: uppercase; }
.max-hr-value { font-size: 3rem; font-weight: 800; color: #dc2626; }
.max-hr-unit { font-size: 1.2rem; color: #dc2626; font-weight: 600; }
.method-used { display: block; font-size: 0.82rem; color: #94a3b8; margin-top: 4px; }
.zones-table { text-align: left; margin: 24px 0; }
.zone-row { display: flex; align-items: center; gap: 16px; padding: 14px 16px; border-radius: 10px; margin-bottom: 8px; }
.zone-row.zone1 { background: #eff6ff; border-left: 4px solid #3b82f6; }
.zone-row.zone2 { background: #ecfdf5; border-left: 4px solid #22c55e; }
.zone-row.zone3 { background: #fefce8; border-left: 4px solid #eab308; }
.zone-row.zone4 { background: #fff7ed; border-left: 4px solid #f97316; }
.zone-row.zone5 { background: #fef2f2; border-left: 4px solid #ef4444; }
.zone-info { min-width: 140px; }
.zone-number { display: block; font-weight: 800; font-size: 0.82rem; color: #374151; }
.zone-name { display: block; font-weight: 600; font-size: 0.95rem; color: #1e293b; }
.zone-pct { display: block; font-size: 0.75rem; color: #94a3b8; }
.zone-range { font-size: 1.4rem; font-weight: 800; color: #dc2626; min-width: 140px; }
.zone-purpose { font-size: 0.85rem; color: #64748b; flex: 1; }
.zone-visual { text-align: left; margin: 24px 0; }
.zone-bars { display: flex; height: 40px; border-radius: 20px; overflow: hidden; }
.zone-bar { display: flex; align-items: center; justify-content: center; font-size: 0.72rem; font-weight: 700; color: #fff; transition: width 0.6s ease; }
.zone-bar.z1 { background: #3b82f6; }
.zone-bar.z2 { background: #22c55e; }
.zone-bar.z3 { background: #eab308; }
.zone-bar.z4 { background: #f97316; }
.zone-bar.z5 { background: #ef4444; }
.training-tips { text-align: left; margin: 24px 0; }
.tip-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; }
.tip-card { background: #f8fafc; border: 1px solid #e2e8f0; border-radius: 10px; padding: 16px; }
.tip-goal { display: block; font-weight: 700; font-size: 0.92rem; color: #dc2626; margin-bottom: 6px; }
.tip-text { font-size: 0.85rem; color: #475569; }
.retake-btn { background: transparent; border: 2px solid #ef4444; color: #ef4444; padding: 10px 28px; border-radius: 8px; font-size: 0.95rem; font-weight: 600; cursor: pointer; margin-top: 16px; transition: all 0.2s; }
.retake-btn:hover { background: #ef4444; color: #fff; }
.education-tabs { background: #fff; border: 1px solid #e2e8f0; border-radius: 14px; padding: 28px; margin-bottom: 28px; }
.tab-nav { display: flex; gap: 6px; border-bottom: 2px solid #e2e8f0; margin-bottom: 24px; overflow-x: auto; }
.tab-btn { background: none; border: none; padding: 10px 16px; font-size: 0.88rem; font-weight: 600; color: #64748b; cursor: pointer; border-bottom: 3px solid transparent; margin-bottom: -2px; white-space: nowrap; transition: color 0.2s, border-color 0.2s; }
.tab-btn.active, .tab-btn:hover { color: #dc2626; border-bottom-color: #dc2626; }
.tab-content { display: none; }
.tab-content.active { display: block; }
.tab-content h3 { color: #dc2626; margin-top: 0; }
.tab-content h4 { color: #374151; margin-top: 20px; }
.tab-content p { color: #475569; }
.tab-content ul { color: #475569; padding-left: 20px; }
.tab-content li { margin-bottom: 6px; }
.faq-section { background: #fff; border: 1px solid #e2e8f0; border-radius: 14px; padding: 28px; margin-bottom: 28px; }
.faq-section h2 { color: #dc2626; margin-top: 0; }
.faq-item { border-bottom: 1px solid #e2e8f0; }
.faq-item:last-child { border-bottom: none; }
.faq-question { width: 100%; background: none; border: none; padding: 16px 0; text-align: left; font-size: 1rem; font-weight: 600; color: #1e293b; cursor: pointer; display: flex; justify-content: space-between; align-items: center; }
.faq-question::after { content: '+'; font-size: 1.4rem; color: #ef4444; font-weight: 300; }
.faq-item.active .faq-question::after { content: '\2212'; }
.faq-answer { max-height: 0; overflow: hidden; transition: max-height 0.35s ease; }
.faq-item.active .faq-answer { max-height: 500px; }
.faq-answer p { padding: 0 0 16px; color: #475569; margin: 0; font-size: 0.95rem; }
.medical-disclaimer { background: #fef9ee; border: 1px solid #fde68a; border-radius: 12px; padding: 20px 24px; margin-bottom: 28px; }
.medical-disclaimer h3 { color: #92400e; margin: 0 0 8px; font-size: 1rem; }
.medical-disclaimer p { margin: 0; font-size: 0.88rem; color: #78716c; }
.related-calculators { margin-bottom: 28px; }
.related-calculators h2 { color: #dc2626; }
.related-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; }
.related-card { display: flex; flex-direction: column; align-items: center; text-align: center; background: #fff; border: 1px solid #e2e8f0; border-radius: 12px; padding: 20px 12px; text-decoration: none; transition: transform 0.2s, box-shadow 0.2s; }
.related-card:hover { transform: translateY(-3px); box-shadow: 0 6px 16px rgba(0,0,0,0.1); }
.related-icon { font-size: 2rem; margin-bottom: 8px; }
.related-title { font-weight: 700; color: #1e293b; font-size: 0.9rem; margin-bottom: 4px; }
.related-desc { color: #64748b; font-size: 0.78rem; }
.references-section { background: #f8fafc; border: 1px solid #e2e8f0; border-radius: 12px; padding: 20px 24px; margin-bottom: 28px; }
.references-section h3 { margin: 0 0 12px; color: #475569; font-size: 1rem; }
.references-list { margin: 0; padding-left: 20px; }
.references-list li { font-size: 0.82rem; color: #64748b; margin-bottom: 8px; }
.references-list a { color: #dc2626; }
@media (max-width: 768px) {
    .hrzone-hero { padding: 32px 20px; }
    .hrzone-hero h1 { font-size: 1.6rem; }
    .hrzone-stats { grid-template-columns: 1fr; }
    .calculator-form-section { padding: 20px; }
    .field-row { flex-direction: column; gap: 0; }
    .zone-row { flex-direction: column; align-items: flex-start; gap: 6px; }
    .zone-range { min-width: auto; }
    .tip-grid { grid-template-columns: 1fr; }
    .related-grid { grid-template-columns: repeat(2, 1fr); }
    .tab-btn { padding: 8px 10px; font-size: 0.78rem; }
    .results-section { padding: 20px; }
}