/* Shared lesson styles for AIkiPadhai Class 9 Science lessons */
body { font-family: 'Inter', system-ui, sans-serif; background: #fafafa; color: #333; margin: 0; line-height: 1.7; }
header.lesson-head { background: #065f46; color: white; text-align: center; padding: 25px 15px; }
header.lesson-head h1 { margin: 0; font-size: 26px; color: #fff; }
header.lesson-head nav { margin-top: 8px; }
header.lesson-head nav a { color: #d1fae5; text-decoration: none; margin: 0 10px; font-weight: 600; font-size: 15px; }
header.lesson-head nav a:hover { color: #fff; }
main { max-width: 900px; margin: 30px auto; padding: 20px; background: #fff; border-radius: 12px; box-shadow: 0 3px 8px rgba(0,0,0,0.05); }
.content-section { margin-bottom: 35px; }
.content-section h2 { font-size: 24px; color: #065f46; border-bottom: 2px solid #e0e0e0; padding-bottom: 8px; margin-bottom: 18px; }
.content-section h3 { font-size: 20px; color: #047857; margin-top: 22px; }
p, li { font-size: 17px; color: #444; }
code { background: #e4e4e4; padding: 2px 6px; border-radius: 4px; font-family: 'Courier New', monospace; }
.example { background: #f0f5f9; padding: 15px; border-left: 4px solid #0077cc; margin: 20px 0; border-radius: 5px; }
.example-title { font-weight: bold; color: #1e3551; }
.key-point { background: #fffbe6; border: 1px solid #ffe58f; padding: 15px; border-radius: 8px; margin: 20px 0; }
.key-point p { margin: 0; }
.story-box { background: #e8f5e9; border-left: 5px solid #4caf50; padding: 15px; margin: 20px 0; border-radius: 5px; }
.story-title { font-weight: bold; color: #2e7d32; font-size: 18px; margin-bottom: 10px; display: flex; align-items: center; }
.story-title span { margin-right: 10px; font-size: 22px; }
.did-you-know { background: #f3e8ff; border-left: 5px solid #9333ea; padding: 15px; margin: 20px 0; border-radius: 5px; }
.did-you-know .dt { font-weight: bold; color: #7e22ce; font-size: 17px; margin-bottom: 8px; }
.lab-box { background: #ecfeff; border-left: 5px solid #0891b2; padding: 15px; margin: 20px 0; border-radius: 5px; }
.lab-box .lt { font-weight: bold; color: #0e7490; font-size: 17px; margin-bottom: 8px; }
.india-box { background: #fff7ed; border-left: 5px solid #ea580c; padding: 15px; margin: 20px 0; border-radius: 5px; }
.india-box .it { font-weight: bold; color: #c2410c; font-size: 17px; margin-bottom: 8px; }
.health-box { background: #fef2f2; border-left: 5px solid #ef4444; padding: 15px; margin: 20px 0; border-radius: 5px; }
.diagram { text-align: center; margin: 25px 0; }
.diagram svg { max-width: 100%; height: auto; }
.diagram-caption { font-size: 14px; color: #666; margin-top: 8px; font-style: italic; }
.organelle-card { border: 1px solid #e5e7eb; border-radius: 12px; padding: 18px 20px; margin: 18px 0; box-shadow: 0 2px 5px rgba(0,0,0,0.04); }
.organelle-card h3 { margin-top: 0; display: flex; align-items: center; gap: 10px; }
.organelle-card .job { display: inline-block; background: #065f46; color: #fff; font-size: 12px; font-weight: 700; padding: 3px 10px; border-radius: 999px; margin-bottom: 8px; }
table.compare { border-collapse: collapse; width: 100%; margin: 20px 0; font-size: 15px; }
table.compare th, table.compare td { border: 1px solid #d1d5db; padding: 10px; text-align: left; }
table.compare th { background: #065f46; color: #fff; }
table.compare tr:nth-child(even) { background: #f0fdf4; }
.quiz { background: #fff7ed; border: 1px solid #fed7aa; border-radius: 10px; padding: 20px; margin: 25px 0; }
.quiz h3 { margin-top: 0; color: #c2410c; }
.quiz .q { font-weight: 600; margin: 12px 0 8px; }
.quiz button.opt { display: block; width: 100%; text-align: left; background: #fff; border: 1.5px solid #e5e7eb; padding: 10px 14px; margin: 6px 0; border-radius: 8px; cursor: pointer; font-size: 15px; transition: all .15s; }
.quiz button.opt:hover { border-color: #fb923c; }
.quiz button.opt.correct { background: #dcfce7; border-color: #22c55e; }
.quiz button.opt.wrong { background: #fee2e2; border-color: #ef4444; }
.quiz .fb { font-size: 14px; margin-top: 6px; min-height: 20px; font-weight: 600; }
.nav-btns { display: flex; justify-content: space-between; margin-top: 30px; gap: 10px; flex-wrap: wrap; }
.nav-btns a { display: inline-block; padding: 10px 18px; border-radius: 6px; text-decoration: none; font-weight: 600; }
.btn-next { background: #059669; color: #fff; }
.btn-prev { background: #e5e7eb; color: #333; }
.cta-interactive { background: linear-gradient(135deg,#9333ea,#c026d3); color:#fff; padding:18px 22px; border-radius:12px; margin:25px 0; text-align:center; }
.cta-interactive a { display:inline-block; margin-top:10px; background:#fff; color:#7e22ce; font-weight:700; padding:10px 20px; border-radius:8px; text-decoration:none; }
.cta-lab { background: linear-gradient(135deg,#0891b2,#06b6d4); color:#fff; padding:18px 22px; border-radius:12px; margin:25px 0; text-align:center; }
.cta-lab a { display:inline-block; margin-top:10px; background:#fff; color:#0e7490; font-weight:700; padding:10px 20px; border-radius:8px; text-decoration:none; }