@keyframes _si{to{opacity:1}}

.legacy-content .lesson {--accent:#b45309;--accent-deep:#7c3d06;--accent-soft:rgba(180,83,9,.085)}.legacy-content .lesson-header {position:relative;overflow:hidden}.legacy-content .lesson-header:after {content:"";position:absolute;right:-70px;top:-70px;width:220px;height:220px;border:1px solid rgba(180,83,9,.22);border-radius:50%;box-shadow:0 0 0 26px rgba(180,83,9,.04),0 0 0 52px rgba(180,83,9,.025)}.legacy-content .lesson>p {font-size:15px;line-height:2;margin:0 0 20px}.legacy-content .lesson strong {font-weight:700;color:var(--accent-deep)}.legacy-content .lesson mark {background:rgba(180,83,9,.14);color:var(--accent-deep);font-weight:700;padding:2px 5px;border-radius:5px;box-decoration-break:clone;-webkit-box-decoration-break:clone}.legacy-content .lesson .clause {display:block;margin:6px 0;padding:14px 18px;background:var(--accent-soft);border-radius:10px;font-size:14.5px;line-height:1.95;color:var(--text)}.legacy-content .lesson .clause mark {background:rgba(180,83,9,.24)}.legacy-content ol.four {margin:0 0 20px;padding:0;list-style:none;counter-reset:f}.legacy-content ol.four li {counter-increment:f;position:relative;padding-left:32px;margin-bottom:12px;font-size:15px;line-height:2}.legacy-content ol.four li:last-child {margin-bottom:0}.legacy-content ol.four li:before {content:counter(f);position:absolute;left:0;top:5px;width:20px;height:20px;border-radius:50%;background:var(--accent-soft);border:1px solid rgba(180,83,9,.3);color:var(--accent-deep);font-size:11px;font-weight:800;display:flex;align-items:center;justify-content:center}.legacy-content ol.four li b {font-weight:700;color:var(--accent-deep)}.legacy-content .lesson .sec-label {margin:56px 0 20px}.legacy-content .key-line {margin:32px 0;padding:24px;border-radius:14px;background:var(--accent-soft);border:1px solid rgba(180,83,9,.25);text-align:center;font-size:18px;font-weight:800;line-height:1.8;color:var(--accent-deep)}.legacy-content .tpl {background:var(--card);border:1px dashed rgba(180,83,9,.42);border-radius:12px;padding:24px 26px;margin:0 0 20px}.legacy-content .tpl>span {display:block;font-size:11.5px;font-weight:700;letter-spacing:.4px;color:var(--accent-deep);margin-bottom:16px}.legacy-content .tpl ol {margin:0;padding:0;list-style:none;counter-reset:tpl}.legacy-content .tpl li {counter-increment:tpl;position:relative;padding-left:34px;margin-bottom:18px}.legacy-content .tpl li:last-child {margin-bottom:0}.legacy-content .tpl li:before {content:counter(tpl);position:absolute;left:0;top:1px;width:21px;height:21px;border-radius:50%;background:var(--accent-soft);border:1px solid rgba(180,83,9,.3);color:var(--accent-deep);font-size:11px;font-weight:800;display:flex;align-items:center;justify-content:center}.legacy-content .tpl li b {display:block;font-size:12.5px;font-weight:700;color:var(--accent-deep);margin-bottom:5px}.legacy-content .tpl li q {display:block;quotes:"“" "”";font-size:13.5px;line-height:1.95;color:var(--text)}.legacy-content .tpl-note {font-size:13px;line-height:1.9;color:var(--muted);margin:22px 0 0;padding:13px 16px;background:var(--accent-soft);border-radius:8px}.legacy-content .demo {background:var(--card);border:1px solid var(--border);border-radius:var(--radius);padding:28px;box-shadow:var(--shadow-card)}.legacy-content .demo-top {display:flex;justify-content:space-between;align-items:center;gap:14px;flex-wrap:wrap;margin-bottom:20px}.legacy-content .demo-title {font-size:14px;font-weight:700;color:var(--text)}.legacy-content .demo-ctrl {display:flex;gap:12px;flex-wrap:wrap}.legacy-content .demo-ctrl button {display:inline-flex;align-items:center;justify-content:center;gap:7px;padding:10px 20px;min-height:44px;min-width:44px;border:1px solid rgba(180,83,9,.35);border-radius:999px;background:var(--accent-soft);color:var(--accent-deep);font:600 14px/1 -apple-system,BlinkMacSystemFont,"PingFang SC",sans-serif;cursor:pointer;transition:filter .15s}.legacy-content .demo-ctrl button:active {filter:brightness(.92)}.legacy-content .dm-pips {display:grid;grid-template-columns:1fr 1fr;gap:12px;margin-bottom:16px}.legacy-content .dm-pip {padding:12px 14px;border-radius:12px;border:1px solid var(--border);background:var(--bg);min-width:0;opacity:1;transform:scale(1);transition:all .35s cubic-bezier(.4,0,.2,1)}.legacy-content .demo.playing .dm-pip {opacity:.4;transform:scale(.98)}.legacy-content .demo.playing .dm-pip.on {opacity:1;transform:scale(1);border-color:rgba(180,83,9,.4);background:var(--accent-soft)}.legacy-content .dm-pip b {display:block;font-size:13px;color:var(--text);margin-bottom:4px}.legacy-content .dm-pip span {display:block;font-size:12px;line-height:1.6;color:var(--sub)}.legacy-content .dm-pip.on {border-color:rgba(180,83,9,.4);background:var(--accent-soft)}.legacy-content .dm-pip.on b {color:var(--accent-deep)}.legacy-content .dm-pip.done {border-color:rgba(22,163,74,.35);background:rgba(22,163,74,.07)}.legacy-content .dm-pip.pop {animation:flashPop .8s ease}@keyframes flashPop{0%{transform:scale(.8)}30%{transform:scale(1.15)}100%{transform:scale(1)}}.legacy-content .dm-track {height:4px;border-radius:99px;background:var(--border);margin:0 0 20px;overflow:hidden}.legacy-content .dm-bar {height:100%;width:0;background:var(--accent);border-radius:99px;transition:width .6s cubic-bezier(.25,1,.5,1)}.legacy-content .dm-compare {display:grid;grid-template-columns:1fr 1fr;gap:20px}.legacy-content .dm-cmp-col {border:1px solid var(--border);border-radius:12px;background:var(--bg);overflow:hidden;min-width:0}.legacy-content .dm-cmp-h {padding:14px 16px;background:var(--card);border-bottom:1px solid var(--border);font-size:13px;font-weight:800;color:var(--text)}.legacy-content .dm-pane {padding:16px 18px;font-size:13.5px;line-height:1.9;color:var(--text);min-height:212px;overflow-wrap:anywhere;word-break:break-word;transition:min-height .5s cubic-bezier(.25,1,.5,1)}.legacy-content .dm-empty {color:var(--sub);font:13px/1.8 -apple-system,BlinkMacSystemFont,"PingFang SC",sans-serif}.legacy-content .dm-enter {opacity:0;transform:translateY(10px)}.legacy-content .dm-enter.show {opacity:1;transform:none;transition:opacity .4s cubic-bezier(.25,1,.5,1),transform .4s cubic-bezier(.25,1,.5,1)}.legacy-content .dm-body {max-height:0;overflow:hidden;padding:0;transition:max-height .5s cubic-bezier(.25,1,.5,1),padding .4s cubic-bezier(.25,1,.5,1)}.legacy-content .dm-body.open {max-height:460px;padding:2px 0 4px}.legacy-content .dm-io {display:flex;flex-direction:column;gap:12px}.legacy-content .dm-i {padding:12px 14px;border-radius:10px;background:var(--card);border:1px solid var(--border);opacity:0;transform:translateY(8px)}.legacy-content .dm-i.show {opacity:1;transform:none;transition:opacity .45s cubic-bezier(.25,1,.5,1),transform .45s cubic-bezier(.25,1,.5,1)}.legacy-content .dm-i i {display:block;font-style:normal;font-size:11.5px;font-weight:800;letter-spacing:.5px;color:var(--accent);margin-bottom:5px}.legacy-content .dm-i p {margin:0;font-size:13px;line-height:1.85;color:var(--text)}.legacy-content .dm-i.back {background:var(--accent-soft);border-color:rgba(180,83,9,.24)}.legacy-content .dm-read {display:flex;flex-direction:column;gap:12px;margin-top:12px}.legacy-content .dm-r {padding:12px 14px;border-radius:10px;background:var(--card);border:1px solid var(--border);opacity:0;transform:translateY(8px)}.legacy-content .dm-r.show {opacity:1;transform:none;transition:opacity .5s cubic-bezier(.25,1,.5,1),transform .5s cubic-bezier(.25,1,.5,1)}.legacy-content .dm-r b {display:block;font-size:12.5px;margin-bottom:6px;color:var(--accent-deep)}.legacy-content .dm-r p {margin:0;font-size:13px;line-height:1.85;color:var(--text)}.legacy-content .dm-r.gap {background:rgba(220,38,38,.05);border-color:rgba(220,38,38,.2)}.legacy-content .dm-r.gap b {color:var(--danger)}.legacy-content .dm-r.ok {background:rgba(22,163,74,.07);border-color:rgba(22,163,74,.28)}.legacy-content .dm-r.ok b {color:var(--success)}.legacy-content .dm-r.ok.glow {animation:fireGlow .9s ease}@keyframes fireGlow{0%{box-shadow:0 0 0 0 rgba(180,83,9,.3)}50%{box-shadow:0 0 20px 6px rgba(180,83,9,.2)}100%{box-shadow:none}}.legacy-content .dm-term {padding:0 3px;border-radius:4px;transition:background .5s cubic-bezier(.25,1,.5,1),color .5s cubic-bezier(.25,1,.5,1)}.legacy-content .dm-term.dim {color:var(--faint)}.legacy-content .dm-term.wake, .legacy-content .dm-term.lit {background:var(--accent-soft);color:var(--accent-deep);font-weight:700}.legacy-content .dm-term.stuck {color:var(--faint);animation:wallPulse 1.2s ease infinite}.legacy-content .dm-term.pop {animation:flashPop .8s ease}@keyframes wallPulse{0%,100%{opacity:1}50%{opacity:.55}}.legacy-content .dm-caption {margin-top:20px;min-height:56px;display:flex;align-items:center;gap:12px;padding:16px 18px;border-radius:10px;background:var(--accent-soft);border:1px solid rgba(180,83,9,.22);font-size:14px;line-height:1.8;color:var(--text)}.legacy-content .dm-caption svg {flex:0 0 auto;color:var(--accent)}.legacy-content .dm-summary {display:flex;flex-direction:column;gap:14px;max-height:0;overflow:hidden;opacity:0;margin-top:0;padding:0 22px;border:1px solid transparent;border-radius:12px;background:linear-gradient(135deg,var(--accent-soft),var(--card));transition:max-height .5s cubic-bezier(.25,1,.5,1),opacity .4s cubic-bezier(.25,1,.5,1),padding .4s cubic-bezier(.25,1,.5,1),margin-top .4s cubic-bezier(.25,1,.5,1)}.legacy-content .dm-summary.on {max-height:240px;opacity:1;margin-top:20px;padding:20px 22px;border-color:rgba(180,83,9,.3)}.legacy-content .dm-summary .dm-s {font-size:13px;line-height:1.8;color:var(--sub)}.legacy-content .dm-summary .dm-s b {display:block;font-size:13.5px;color:var(--accent-deep);margin-bottom:2px}.legacy-content .demo-caption {font-size:11.5px;color:var(--sub);margin-top:14px;line-height:1.7}@media(max-width:760px){.legacy-content .lesson {overflow-x:hidden}.legacy-content .dm-compare, .legacy-content .dm-pips {grid-template-columns:1fr}.legacy-content .lesson-header:after {display:none}.legacy-content .demo {padding:18px}.legacy-content .demo-ctrl {width:100%}.legacy-content .demo-ctrl button {flex:1}.legacy-content .demo {max-width:100%;min-width:0}.legacy-content .lesson code {overflow-wrap:anywhere;word-break:break-word}}@media(prefers-reduced-motion:reduce){.legacy-content .dm-pip, .legacy-content .dm-enter, .legacy-content .dm-enter.show, .legacy-content .dm-body, .legacy-content .dm-bar, .legacy-content .dm-summary, .legacy-content .dm-term, .legacy-content .dm-i, .legacy-content .dm-i.show, .legacy-content .dm-r, .legacy-content .dm-r.show, .legacy-content .dm-pane {transition-duration:0s;animation-duration:0s;animation-iteration-count:1}}

.legacy-content .xa-tldr {margin:18px 0 4px;padding:14px 18px;background:rgba(0,102,255,0.04);border:1px solid rgba(0,102,255,0.16);border-radius:10px}.legacy-content .xa-tldr .xa-tldr-tag {display:block;font-size:11px;font-weight:800;letter-spacing:1px;color:var(--accent,#0066ff);margin-bottom:6px}.legacy-content .xa-tldr p {margin:0;font-size:15px;line-height:1.8;color:var(--text,#1f2937)}