@charset "UTF-8";
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@media(min-width:1440px){.hero{border-radius:6px}.section-nav{margin-top:15px}}
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@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{transition:none!important}}


/* Interactive Earth and earthquake lab */
.earth-panel{background:#fffdf7;border:1px solid var(--line);border-radius:12px;padding:28px;margin-top:24px;overflow:hidden}.earth-panel-head{display:flex;gap:15px;align-items:center;margin-bottom:20px}.earth-number{display:grid;place-items:center;background:var(--teal);color:#f4d293;border-radius:50%;width:40px;height:40px;flex-shrink:0;font-size:12px}.earth-panel-head h3{font:27px var(--serif);margin:0 0 6px}.earth-panel-head p{font-size:12px;color:var(--muted);margin:0}.earth-layout{display:grid;grid-template-columns:1.15fr 1fr;gap:28px;align-items:center}.earth-visual svg{display:block;width:100%;height:auto}.earth-layer{cursor:pointer;outline:none}.earth-layer circle{transition:filter .2s,stroke .2s}.earth-layer[aria-pressed=true]>circle{stroke:#fff7dc;stroke-width:4;filter:brightness(1.13)}.earth-layer:focus-visible>circle{stroke:#143c39;stroke-width:5;stroke-dasharray:5 4}.earth-layer-buttons{display:grid;grid-template-columns:1fr 1fr;gap:7px}.earth-layer-buttons button,.quake-controls button{border:1px solid #b8c7b9;background:transparent;padding:11px 10px;border-radius:6px;color:var(--teal);font:13px var(--sans);min-height:44px;cursor:pointer}.earth-layer-buttons button[aria-pressed=true],.quake-controls button:first-child{background:var(--teal);color:#fff5df}.earth-info{border-left:2px solid #c59465;padding:20px 0 20px 26px}.earth-info h4{font:43px var(--serif);margin:10px 0 4px}.earth-info #earth-layer-zh{font-size:16px;color:var(--muted);margin-bottom:18px}.earth-state{display:inline-block;background:#eee8d8;color:#6a5038;border-radius:20px;padding:5px 12px;font-size:11px}.earth-info>p{font-size:15px;line-height:1.8;margin-top:14px}.earth-info #earth-layer-hint{font-size:12px;color:var(--muted)}.earth-language{margin-top:22px;padding-top:17px;border-top:1px solid var(--line)}.earth-language small{font-size:9px;letter-spacing:1.5px;color:var(--muted)}.earth-language p{font:italic 18px/1.6 var(--serif);margin:8px 0}.earth-key{background:#eaf0e5;padding:18px 20px;font-size:13px;line-height:1.8;margin:24px 0 0}.earth-key span,.earth-small span{display:block;font-size:11px;color:var(--muted);margin-top:7px}.quake-steps{display:grid;grid-template-columns:repeat(4,1fr);gap:7px}.quake-steps button{border:1px solid var(--line);background:transparent;padding:12px 7px;color:var(--teal);font:12px var(--sans);text-align:left;border-radius:5px;cursor:pointer;min-height:65px}.quake-steps button[aria-pressed=true]{background:#e7eddf;border-color:var(--teal);box-shadow:inset 0 -3px var(--teal)}.quake-steps span{display:block;font-size:10px;opacity:.7;margin-bottom:7px}.quake-steps small{display:block;color:var(--muted);font-size:10px;margin-top:5px}.quake-visual{background:#f4f5eb;border-radius:8px;margin-top:20px}.quake-visual svg{display:block;width:100%;height:auto}.quake-caption{padding:23px 0;min-height:185px}.quake-caption>span{font-size:10px;letter-spacing:1px;color:var(--muted)}.quake-caption h4{font:26px var(--serif);margin:9px 0}.quake-caption p{font-size:14px;line-height:1.8;margin:7px 0}.quake-caption [lang=zh]{color:var(--muted);font-size:12px}.quake-controls{display:flex;gap:8px;flex-wrap:wrap}.quake-controls button:disabled{opacity:.4;cursor:default}.earth-small,.earth-sources{font-size:11px;line-height:1.8;color:var(--muted);margin-top:18px}.quake-origin,.quake-waves,.quake-wave-label,.quake-lock{opacity:0;transition:opacity .4s}.quake-panel[data-step="0"] .quake-lock,.quake-panel[data-step="1"] .quake-lock{opacity:1}.quake-panel[data-step="2"] .quake-origin,.quake-panel[data-step="3"] .quake-origin,.quake-panel[data-step="3"] .quake-waves,.quake-panel[data-step="3"] .quake-wave-label{opacity:1}#quake-rock-left,#quake-rock-right,.quake-strata{transition:transform 1s,d 1s}.quake-panel[data-step="2"] #quake-rock-right,.quake-panel[data-step="3"] #quake-rock-right{transform:translate(10px,-14px)}.quake-panel[data-step="2"] #quake-rock-left,.quake-panel[data-step="3"] #quake-rock-left{transform:translate(-4px,6px)}.quake-loading{opacity:.75}.quake-panel[data-step="3"] .quake-loading{opacity:.2}.quake-panel[data-step="3"][data-playing="true"] .quake-wave{transform-box:fill-box;transform-origin:center;animation:earth-wave 2.2s ease-out infinite}.quake-wave:nth-child(2){animation-delay:.2s!important}.quake-wave:nth-child(3){animation-delay:.4s!important}.quake-wave:nth-child(4){animation-delay:.6s!important}@keyframes earth-wave{0%{opacity:.2;scale:.9}50%{opacity:.85}100%{opacity:.12;scale:1.15}}
@media(max-width:600px){.earth-panel{padding:18px 14px}.earth-panel-head h3{font-size:23px}.earth-panel-head p{font-size:10px}.earth-layout{grid-template-columns:1fr;gap:18px}.earth-info{padding:12px 0 12px 18px}.earth-info h4{font-size:35px}.earth-info>p{font-size:14px}.quake-steps{grid-template-columns:1fr 1fr}.quake-steps button{min-height:65px}.quake-caption{min-height:215px}.quake-controls{display:grid;grid-template-columns:1fr 1fr}.quake-controls button{font-size:11px}.quake-visual{margin-left:-8px;margin-right:-8px}.quake-visual svg{min-height:195px}.earth-key{padding:14px;font-size:12px}.earth-sources{font-size:10px}}
@media(prefers-reduced-motion:reduce){.earth-layer circle,#quake-rock-left,#quake-rock-right,.quake-strata,.quake-origin,.quake-waves,.quake-lock{transition:none}.quake-wave{animation:none!important}}

/* Fixed-view dimensional art with semantic, keyboard-accessible hit regions. */
.earth-layout-3d{display:block}.earth-space-frame{position:relative;background:#050e1d;border-radius:10px;overflow:hidden}.earth-space-frame svg{width:100%;display:block;animation:earth-reveal-in 1.2s ease both}.earth-space-tag{position:absolute;left:20px;top:15px;color:#acc6dc;font-size:9px;letter-spacing:2px;pointer-events:none}.earth-hit>path,.earth-hit>ellipse{fill:transparent;stroke:transparent;stroke-width:4;transition:stroke .3s,fill .3s}.earth-hit[aria-pressed=true]>path,.earth-hit[aria-pressed=true]>ellipse{fill:#ffc77612;stroke:#ffe2a3b0}.earth-hit:focus-visible>path,.earth-hit:focus-visible>ellipse{stroke:#fff;stroke-width:6;stroke-dasharray:10 7}.earth-3d-label{color:#cae1f0;pointer-events:none}.earth-3d-label path{fill:none;stroke:currentColor;stroke-width:3}.earth-3d-label circle{fill:currentColor}.earth-3d-label text{fill:currentColor;font:32px Arial,sans-serif}.earth-hit[aria-pressed=true] .earth-3d-label{color:#ffe1a0}.earth-space-frame.hide-labels .earth-3d-label{opacity:0}.earth-layout-3d .earth-info{margin-top:24px;border-left:0;border-top:1px solid var(--line);padding:22px 0 0;display:grid;grid-template-columns:1fr 1.6fr;gap:4px 35px}.earth-layout-3d .earth-info>.eyebrow{grid-column:1;grid-row:1}.earth-layout-3d .earth-info h4{grid-column:1;grid-row:2}.earth-layout-3d #earth-layer-zh{grid-column:1;grid-row:3;margin:0}.earth-layout-3d #earth-layer-state{grid-column:1;grid-row:4;justify-self:start;align-self:start;margin-top:10px}.earth-layout-3d #earth-layer-description{grid-column:2;grid-row:1 / 3;margin-top:0}.earth-layout-3d #earth-layer-hint{grid-column:2;grid-row:3 / 5}.earth-layout-3d .earth-language{grid-column:1 / -1;margin-top:18px}.earth-layout-3d .earth-layer-buttons{grid-template-columns:repeat(4,1fr);margin-top:14px}.earth-view-controls{display:flex;gap:15px;justify-content:flex-end;margin:10px 0}.earth-view-controls button{border:0;background:transparent;color:var(--muted);font:11px var(--sans);text-decoration:underline;text-underline-offset:4px;min-height:40px;padding:6px;cursor:pointer}.earth-space-frame.reveal-again svg{animation:earth-reveal-again 1.2s ease both}@keyframes earth-reveal-in{from{opacity:0;transform:scale(.95)}to{opacity:1;transform:scale(1)}}@keyframes earth-reveal-again{from{opacity:.1;transform:scale(.95)}to{opacity:1;transform:scale(1)}}
@media(max-width:600px){.earth-space-frame svg{width:680px;max-width:none}.earth-space-frame{overflow-x:auto;scrollbar-width:thin;scrollbar-color:#8dabbf #071426}.earth-space-tag{position:sticky;left:14px;display:block;bottom:12px;width:max-content;font-size:8px;margin-top:-16px}.earth-layout-3d .earth-layer-buttons{grid-template-columns:1fr 1fr}.earth-layout-3d .earth-info{display:block}.earth-layout-3d #earth-layer-description{margin-top:18px}.earth-layout-3d #earth-layer-hint{margin-top:10px}.earth-view-controls{justify-content:space-between;gap:5px}}
@media(prefers-reduced-motion:reduce){.earth-space-frame svg{animation:none!important}.earth-hit>path,.earth-hit>ellipse{transition:none}}

.earth-art-note{font-size:11px;line-height:1.8;color:var(--muted);margin:12px 0}.earth-space-frame{scroll-behavior:smooth}@media(prefers-reduced-motion:reduce){.earth-space-frame{scroll-behavior:auto}}

/* Dimensional fault cutaway: geometry remains animatable and selectable. */
.quake-visual-3d{background:#040c18;border:1px solid #2b3e4e;overflow:hidden}.quake-visual-3d svg{display:block;width:100%;height:auto}.quake-term-buttons{display:grid;grid-template-columns:repeat(4,1fr);gap:8px;margin-top:18px}.quake-term-buttons button{min-height:60px;border:1px solid var(--line);background:transparent;color:var(--teal);padding:10px 6px;border-radius:6px;cursor:pointer;font:13px var(--sans)}.quake-term-buttons button[aria-pressed=true]{background:#e7eddf;border-color:var(--teal)}.quake-term-buttons span{display:block;font-size:10px;color:var(--muted);margin-top:6px}.quake-term-info{font-size:12px;line-height:1.8;color:var(--muted);padding:15px 0;border-bottom:1px solid var(--line);min-height:72px}.quake-stress{opacity:0;transition:opacity .4s}.quake-panel[data-step="1"] .quake-stress{opacity:1}.quake-fault-glow{opacity:0;transition:opacity .4s}.quake-panel[data-step="2"] .quake-fault-glow,.quake-panel[data-term="fault"] .quake-fault-glow{opacity:.8}.quake-visual-3d .quake-waves{stroke-width:2;stroke-opacity:.85}.quake-visual-3d .quake-origin{transition:opacity .4s}.quake-panel[data-term="focus"] .quake-origin,.quake-panel[data-term="epicenter"] .quake-origin,.quake-panel[data-term="waves"] .quake-waves,.quake-panel[data-term="waves"] .quake-wave-label{opacity:1}.quake-panel[data-step="2"] #quake-rock-right,.quake-panel[data-step="3"] #quake-rock-right{transform:translate(10px,-15px)}.quake-panel[data-step="2"] #quake-rock-left,.quake-panel[data-step="3"] #quake-rock-left{transform:translate(-4px,6px)}
@media(max-width:600px){.quake-visual-3d{overflow-x:auto;scrollbar-width:thin;margin-left:0;margin-right:0}.quake-visual-3d svg{width:680px;min-height:0;max-width:none}.quake-term-buttons{grid-template-columns:1fr 1fr}.quake-term-info{font-size:11px;min-height:90px}}
@media(prefers-reduced-motion:reduce){.quake-stress,.quake-fault-glow{transition:none}}

/* Left block is the hanging wall: reverse-fault slip is up-dip. */
.quake-panel[data-step="2"] #quake-rock-left,.quake-panel[data-step="3"] #quake-rock-left{transform:translate(10px,-15px)}
.quake-panel[data-step="2"] #quake-rock-right,.quake-panel[data-step="3"] #quake-rock-right{transform:translate(-4px,6px)}