/* The painted railway classroom. Circuit and answer colors keep their meaning. */
@media screen{
:root{--paper:#f6ece5;--white:#fff8f0;--ink:#4b3f52;--muted:#796b7b;--line:#dfcdd7;--green:#80647e;--green-light:#eddee6;--radius:4px;--serif:"Iowan Old Style","Palatino Linotype","Noto Serif SC","Source Han Serif SC","Songti SC","STSong",SimSun,serif}
body{background:radial-gradient(ellipse at 95% 0%,#f0c1b03b,transparent 45%),var(--paper)}
::selection{background:#efd0c4;color:#503e53}
button{border-radius:7px}
button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible{outline-color:#aa7a91}
.sidebar{background:linear-gradient(180deg,#40364c,#352e43);color:#e8d9e4;border-right:1px solid #d8b8cf28}
.brand{font-family:var(--serif);font-size:26px;font-weight:400;letter-spacing:1px;color:#ffeddd;gap:14px}
.brand small{font-family:"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;font-size:10px;color:#cbb5c8;letter-spacing:3px}
.brand-mark{color:#f4d3a0;position:relative;width:33px;height:39px;flex-shrink:0;display:block}
.brand-mark i{position:absolute;bottom:3px;left:12px;width:2px;height:24px;background:currentColor;transform:rotate(-8deg);border-radius:2px}
.brand-mark i:before,.brand-mark i:after{content:"";position:absolute;left:-8px;top:3px;width:10px;height:16px;background:currentColor;clip-path:polygon(8% 2%,100% 25%,85% 88%,36% 100%,0 49%);transform:rotate(-28deg);box-shadow:none}
.brand-mark i:after{left:1px;top:9px;width:10px;height:14px;transform:rotate(148deg);box-shadow:none}
.main-nav{border-color:#d8b8cf30}
.main-nav a{color:#ecdee8;border-radius:5px}
.main-nav span{color:#c8b2c7}
.main-nav a:hover,.main-nav a.active,.lesson-nav a:hover,.lesson-nav a.active{background:#66506b;color:#f5d7be}
.nav-label,.sidebar-foot{color:#c5adc3}
.lesson-nav a{border-radius:10px;color:#dcc5d6}
.lesson-nav .lesson-number{color:#b49ab1}
.lesson-nav .done .lesson-number{color:#f4d3a0}
.topbar{background:#f7ede7ed;border-color:#dfcdd7}
.small-button{background:#fff7ef;border-radius:5px}
main{position:relative}
h1,h2,h3,.day h3{font-family:var(--serif);font-weight:400;letter-spacing:.3px}
h1{font-size:40px;line-height:1.55}
h2{font-size:27px}
.hero{border-bottom-color:#dbc3cf;padding-bottom:39px}
.hero h1{color:#6e526e}
.eyebrow{letter-spacing:2.5px;font-size:10px}
.hero-symbol{opacity:.88}
.actions a,.button-link{border-radius:7px}
.study-stats{border-color:#dcc8d3}
.study-stats strong{color:#8b667f}
.day{border-color:#dfcdd7}
.day-label{color:#97718a;font-size:12px;letter-spacing:1px}
.topic-links a{text-decoration-color:#c8a6ba}
.note,.lab-prompt{background:#f0dedc;border-color:#c89eaa;border-radius:5px}
.formula{border-radius:7px;background:#eddee6;border-left-color:#b48b9e}
.example,.controls,.formula-sheet{background:#fff8f0;border-color:#ddc7d3;border-radius:8px;box-shadow:0 4px 16px #5b3f5703}
.option{border-color:#ddc7d3;border-radius:7px}
.option:has(input:checked){background:#eedee7;border-color:#b28b9e}
.answer-input,.control select,.lab-tabs a{border-radius:7px}
.lab-tabs a.active{background:#80647e}
.readout{border-bottom-color:#d8c1d0}
.empty-state{background:#eedee7;border-radius:8px}
.page-foot{color:#967b8e}
#toast{background:#40364c;border:1px solid #cda9c150;border-radius:7px;color:#ffeadc}
@media(max-width:800px){h1{font-size:31px}h2{font-size:25px}.topbar{padding-inline:13px;gap:8px}.brand{font-size:25px}.menu-open .sidebar{box-shadow:10px 0 50px #2d233b66}}
@media(max-width:360px){main{padding-inline:18px}.topbar{font-size:10px;gap:7px}#progress{font-size:9px}.small-button{font-size:11px;padding-inline:8px}.study-stats{gap:22px}.study-stats strong{font-size:23px}.study-stats span{font-size:10px}.day{grid-template-columns:53px 1fr;gap:11px}.day h3{font-size:18px}.controls{gap:12px;padding:14px}.control label{font-size:12px}}
}