/* Semester 4A: independent study pages. Isolated supplement to existing site. */
.a4-main{max-width:1010px;margin:auto;padding:22px 20px 80px;color:#213948;font-family:system-ui,Arial,sans-serif;line-height:1.6}
.a4-main h1,.a4-main h2,.a4-main h3{font-family:Georgia,serif;color:#173b50;line-height:1.2}
.a4-main h1{font-size:clamp(29px,4vw,43px);margin:.3em 0}.a4-main h2{font-size:1.52rem;margin:1.1em 0 .6em}.a4-main h3{font-size:1.15rem}
.a4-crumb{font-size:.84rem;color:#496272;display:flex;flex-wrap:wrap;gap:8px}.a4-crumb a{color:#14647c}.a4-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(225px,1fr));gap:15px}
.a4-card{background:#fff;border:1px solid #d5e0e5;box-shadow:0 3px 14px #173b5010;border-radius:14px;padding:18px}.a4-card h3{margin:0 0 8px}
.a4-tags{display:flex;gap:7px;flex-wrap:wrap;margin:12px 0}.a4-tag{background:#e2f1ed;color:#165c5b;border-radius:30px;padding:4px 10px;font-size:.77rem;font-weight:700}
.a4-note{padding:15px 18px;border-left:4px solid #287b84;background:#eff8f9;border-radius:7px;margin:16px 0}
.a4-example{background:#f5faff;border:1px solid #cbdee9;border-radius:12px;margin:14px 0;padding:16px}
.a4-question{margin:10px 0;padding:14px;background:#fff;border:1px solid #d5e0e5;border-radius:10px;break-inside:avoid}
.a4-question p{margin:4px 0 10px}.a4-answer{border-top:1px solid #c9dce3;padding:11px 0 3px;margin-top:10px}
.a4-answer strong{display:block;color:#176158}.a4-question details summary{color:#186478;font-weight:700;cursor:pointer;min-height:32px}
.a4-number{font-size:.74rem;color:#537186;font-weight:700;text-transform:uppercase;letter-spacing:.04em}
.a4-visual{max-width:100%;width:min(100%,400px);margin:10px auto;display:block}.math-visual{display:block;width:min(100%,400px);height:auto;margin:12px auto;background:#fff;border-radius:8px;overflow:visible}
.a4-terms{display:grid;grid-template-columns:minmax(100px,200px) 1fr;gap:8px}.a4-terms dt{font-weight:bold;color:#1d5d69}.a4-terms dd{margin:0}
.a4-table{border-collapse:collapse;width:100%;font-size:.91rem}.a4-table td,.a4-table th{padding:9px;border-bottom:1px solid #cbdbe2;text-align:left}
.a4-links{display:flex;justify-content:space-between;gap:10px;flex-wrap:wrap;margin-top:28px;padding-top:19px;border-top:1px solid #c9dce3}
.a4-links a,.a4-cta{color:#fff!important;background:#146a72;display:inline-block;text-decoration:none;border-radius:8px;padding:10px 15px;font-weight:700}.a4-cta{background:#1b566d}
.a4-printspace{display:none}.a4-stats{color:#536d7e;font-size:.86rem}.a4-warning{background:#fff8ea;border:1px solid #e9c988;border-radius:9px;padding:12px 15px;margin:20px 0}
@media(max-width:550px){.a4-main{padding:20px 14px}.a4-terms{grid-template-columns:1fr}.a4-terms dd{margin-bottom:8px}.a4-question{padding:11px}.a4-card{padding:13px}}
@media print{@page{size:letter;margin:0.63in}body{background:#fff!important;color:#000}.curr-nav,.a4-links,.a4-crumb,.a4-cta,footer{display:none!important}.a4-main{max-width:none;padding:0;color:#000;font-size:10.5pt}.a4-main h1{font-size:20pt}.a4-main h2{font-size:13pt}.a4-card,.a4-example,.a4-question{box-shadow:none;border:1px solid #b9b9b9;break-inside:avoid}.a4-printspace{display:block;height:38px;border-bottom:1px dotted #bbb}.a4-question details{display:none}.a4-question .a4-visual{max-height:170px}.a4-solution-print .a4-answer{display:block}.math-visual{max-width:300px}}