:root{color-scheme:light;--blue:#066bc4;--navy:#112e57;--muted:#66798e}*{box-sizing:border-box}html,body{margin:0;width:100%;height:100%;overflow:hidden}body{font:22px/1.35 "PingFang SC","Microsoft YaHei",sans-serif;color:var(--navy);background:white}
#slide{position:absolute;width:1280px;height:720px;padding:24px;display:grid;grid-template-rows:44px 46px 28px 490px 32px;gap:8px;transform-origin:top left;background:white}
header,.controls,footer{display:flex;align-items:center;gap:16px}h1{font-size:29px;margin:0 auto 0 0;font-weight:650}button,select{font:inherit;height:38px;border:1px solid #bfcfdf;border-radius:5px;background:white;color:var(--navy);padding:0 12px}button{cursor:pointer;transition:background .15s,color .15s}button:hover{background:#e4f1fc;color:var(--blue)}button:focus-visible,select:focus-visible{outline:3px solid #378bd6;outline-offset:3px}.controls{border-bottom:1px solid #dce5ed;padding-bottom:6px;font-size:20px}.spacer{flex:1}select{width:210px}.guide{margin:0;color:var(--muted);font-size:19px}.katex{font-size:1em}
#experiments{display:grid;grid-template-rows:150px 150px 190px}.experiment{position:relative;border-bottom:1px solid #d7e2ec}.experiment:last-child{background:#eef6fc;border:0;border-radius:10px}h2{position:absolute;top:10px;left:18px;margin:0;font-size:23px;font-weight:600}.experiment>button{position:absolute;top:8px;right:18px;font-size:18px;z-index:2;height:34px;min-width:104px}.experiment svg{position:absolute;inset:0;width:100%;height:100%}.label{position:absolute;white-space:nowrap}.input{left:32px;top:63px;font-size:29px}.device-label{top:67px;left:260px;width:120px;text-align:center;font-size:26px}.second-device{left:760px}.outlet{left:1004px;font-size:27px;display:flex;align-items:baseline;gap:10px}.outlet.positive{top:46px}.outlet.negative{top:103px}.value{font-weight:650;color:var(--blue);font-size:30px;min-width:76px}.counts{font-size:17px;color:var(--muted)}.retained{top:46px;left:426px;font-size:20px;color:var(--blue)}.current{top:81px;left:558px;font-size:26px}.blocked{top:151px;left:526px;font-size:20px;color:var(--muted)}.fraction-note{top:154px;left:895px;font-size:17px;color:var(--muted)}.experiment[data-revealed=true] .value{animation:appear .2s ease-out}footer{justify-content:space-between;font-size:18px;color:var(--muted)}@keyframes appear{from{opacity:.2}to{opacity:1}}@media(prefers-reduced-motion:reduce){*{animation:none!important;transition:none!important}}

/* Match classroom hierarchy while preserving the three comparison rows. */
h1{font-size:40px}h2{font-size:28px}.controls{font-size:24px}select{width:230px}
.guide{font-size:22px}.input,.device-label,.current{font-size:32px}
.outlet{font-size:30px}.value{font-size:32px}.counts{font-size:22px}
.retained,.blocked{font-size:22px}.fraction-note{font-size:22px}
.experiment>button{font-size:22px;height:36px;min-width:118px}
footer{font-size:20px}.experiment[data-revealed=true] .value{animation:none}