:root{--green:#0d3328;--green2:#164737;--green3:#245b45;--paper:#f2ead8;--cream:#fff9eb;--gold:#c6aa6a;--water:#75b9ba;--ink:#17372d;--muted:#aebfb4;--danger:#bf6545;--ok:#6e9a64;--shadow:0 18px 45px rgba(3,16,12,.24)}
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/* V2: chapter order, illustration material pack, and Chapter 02 code lock */
.locked-card{position:relative;overflow:hidden}.locked-card::after{content:"LOCKED";position:absolute;right:-28px;top:14px;transform:rotate(35deg);background:#a58a48;color:#fff9eb;font-size:9px;letter-spacing:.14em;padding:5px 34px}.unlocked-card{border-color:rgba(197,220,173,.38);background:rgba(153,190,121,.12)}
.illustrated-card{background:linear-gradient(180deg,#f5efdf,#e9dfc8);border-color:rgba(235,220,180,.35)}.illustrated-card img{max-height:390px;object-fit:contain;padding:12px;background:transparent}.illustrated-card figcaption{background:rgba(13,51,40,.95)}.compact-top{margin-top:14px}.illustration-pair{align-items:stretch}.illustration-pair .diagram-card{display:flex;flex-direction:column}.illustration-pair .diagram-card img{height:260px;object-fit:contain}.illustration-pair .diagram-card figcaption{margin-top:auto}.bridge-diagram img{height:250px;object-fit:contain;padding:18px 10px;background:linear-gradient(180deg,#f5efdf,#eee2c7)}
.unlock-screen{padding-top:58px;text-align:center;background:radial-gradient(circle at 50% 12%,rgba(198,170,106,.17),transparent 35%)}.unlock-screen h2{margin-bottom:12px}.unlock-compass{width:92px;opacity:.78;margin:0 auto 20px;display:block}.code-panel{max-width:430px;margin:30px auto 0;padding:20px;border-radius:24px;border:1px solid rgba(242,234,216,.16);background:rgba(242,234,216,.07);box-shadow:var(--shadow)}.code-panel label{display:block;font-size:10px;letter-spacing:.24em;color:#d5c894;margin-bottom:10px}.code-panel input{width:100%;height:68px;border-radius:16px;border:1px solid rgba(255,255,255,.2);background:#f2ead8;color:#17372d;text-align:center;font:700 34px Georgia,serif;letter-spacing:.28em;outline:none;padding-left:.28em}.code-panel input:focus{box-shadow:0 0 0 3px rgba(198,170,106,.24)}.code-panel button{width:100%;margin-top:12px;border:none;border-radius:14px;padding:15px;background:#1b5a43;color:#fff9eb;font-weight:800}.unlock-feedback{margin-top:12px;min-height:20px;font-size:12px;color:#aebfb4}.unlock-feedback.success{color:#b9d8a9}.unlock-feedback.error{color:#e7a48d}.shake{animation:codeShake .24s linear}@keyframes codeShake{0%,100%{transform:translateX(0)}25%{transform:translateX(-7px)}75%{transform:translateX(7px)}}
@media (max-width:420px){.illustration-pair{grid-template-columns:1fr 1fr}.illustration-pair .diagram-card img{height:210px}.bridge-diagram img{height:210px}.code-panel input{height:62px;font-size:31px}.screen h2{font-size:clamp(28px,8vw,42px)}}