:root{
  --bg:#f7f6f2; --surface:#ffffff; --ink:#18212f; --muted:#687386; --line:#dde2e8;
  --accent:#315c8a; --accent2:#1f7a68; --warn:#9a6324; --soft:#eef4fa;
  --shadow:0 12px 36px rgba(24,33,47,.08);
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--bg);color:var(--ink);font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;line-height:1.65}
a{color:var(--accent);text-decoration:none}
a:hover{text-decoration:underline}
.wrap{max-width:1180px;margin:auto;padding:0 22px}
.hero{padding:54px 0 32px;background:#102a43;color:#fff}
.hero.small{padding:36px 0 26px}
.hero h1{font-size:clamp(34px,5vw,56px);line-height:1.08;margin:0 0 14px;letter-spacing:-1.4px}
.hero.small h1{font-size:clamp(30px,4vw,44px)}
.hero p{max-width:840px;font-size:17px;color:#e7edf4;margin:0}
.meta{display:flex;flex-wrap:wrap;gap:10px;margin-top:20px}
.pill{display:inline-flex;align-items:center;gap:6px;border-radius:999px;padding:5px 10px;font-size:12px;font-weight:700}
.hero .pill{background:rgba(255,255,255,.12);border:1px solid rgba(255,255,255,.23);color:#fff}
nav{position:sticky;top:0;z-index:20;background:rgba(247,246,242,.94);backdrop-filter:blur(12px);border-bottom:1px solid var(--line)}
nav .wrap{display:flex;gap:8px;overflow:auto;padding-top:10px;padding-bottom:10px}
nav a{white-space:nowrap;padding:7px 11px;border-radius:9px;color:var(--ink);font-size:14px;font-weight:650}
nav a:hover, nav a.active{background:#fff;text-decoration:none}
section{padding:36px 0}
h2{font-size:28px;margin:0 0 18px;letter-spacing:-.6px}
h3{margin:0 0 10px}
.kicker{font-size:12px;font-weight:800;letter-spacing:.12em;text-transform:uppercase;color:var(--accent)}
.grid{display:grid;grid-template-columns:repeat(12,1fr);gap:16px}
.card{background:var(--surface);border:1px solid var(--line);border-radius:16px;padding:20px;box-shadow:var(--shadow)}
.span4{grid-column:span 4}.span6{grid-column:span 6}.span8{grid-column:span 8}.span12{grid-column:span 12}
.stat{font-size:30px;font-weight:800;line-height:1.1}.small{font-size:13px;color:var(--muted)}
.callout{border-left:4px solid var(--accent);padding:13px 16px;background:#eef4fa;border-radius:0 12px 12px 0}
.flow,.code{font-family:ui-monospace,SFMono-Regular,Menlo,monospace;background:#162230;color:#e9eef4;border-radius:14px;padding:18px;overflow:auto;white-space:pre}
.progress-shell{height:10px;background:#e8ebef;border-radius:99px;overflow:hidden}
.progress-bar{height:100%;width:0;background:linear-gradient(90deg,#315c8a,#1f7a68);transition:.25s}
.progress-card{background:var(--surface);border:1px solid var(--line);border-radius:16px;padding:20px;box-shadow:var(--shadow);margin-bottom:18px}
.progress-head{display:flex;align-items:flex-end;justify-content:space-between;gap:18px;margin-bottom:12px}
.progress-meta{display:flex;align-items:center;gap:12px;flex-wrap:wrap}
.sync-status{font-size:12px;color:var(--muted)}
.btn{display:inline-flex;align-items:center;gap:6px;border:1px solid var(--line);background:#fff;border-radius:9px;padding:7px 10px;font-size:13px;font-weight:700;cursor:pointer}
.btn:hover{border-color:#aeb8c4}.btn.primary{background:var(--accent);border-color:var(--accent);color:#fff}
.toolbar{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:18px}
details.week{background:var(--surface);border:1px solid var(--line);border-radius:16px;margin:13px 0;overflow:hidden;box-shadow:0 8px 22px rgba(24,33,47,.05)}
details.week summary{cursor:pointer;list-style:none;padding:18px 20px;display:grid;grid-template-columns:90px 1fr auto;gap:14px;align-items:center}
details.week summary::-webkit-details-marker{display:none}
.weekno{font-weight:850;color:var(--accent);font-size:15px}.weektitle{font-weight:800;font-size:18px}.weekdate{font-size:12px;color:var(--muted);white-space:nowrap}
.weekbody{padding:0 20px 20px;border-top:1px solid var(--line)}
.trackgrid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px;margin-top:16px}
.track{border:1px solid #e3e7ec;background:#fbfcfd;border-radius:12px;padding:14px}
.track h4{margin:0 0 7px;font-size:14px}.track p,.track li{font-size:13px}.track ul{margin:8px 0 0;padding-left:18px}
.tag{font-size:11px;border-radius:999px;padding:3px 7px;font-weight:750;display:inline-block;margin-right:5px}
.t-dsa{background:#e7f0ff;color:#2a5688}.t-hpc{background:#e3f4ef;color:#176455}.t-soft{background:#f3ebff;color:#68429a}.t-sys{background:#fff1df;color:#85561e}.t-tools{background:#edf0f3;color:#4d5a68}
.links{display:flex;flex-wrap:wrap;gap:7px;margin-top:10px}
.links a{font-size:12px;font-weight:700;border:1px solid var(--line);padding:5px 8px;border-radius:8px;background:#fff}
.task{display:flex;gap:9px;align-items:flex-start;margin:7px 0}.task input{margin-top:5px;accent-color:var(--accent)}
.resource{padding:15px 0;border-bottom:1px solid var(--line)}.resource:last-child{border-bottom:0}
.resource strong{display:block}.resource .url{font-family:ui-monospace,SFMono-Regular,Menlo,monospace;font-size:11px;color:var(--muted);overflow-wrap:anywhere}
table{width:100%;border-collapse:collapse;font-size:13px}th,td{padding:10px;border-bottom:1px solid var(--line);vertical-align:top;text-align:left}
th{color:var(--muted);font-size:11px;text-transform:uppercase;letter-spacing:.06em}
details.topic{border-top:1px solid var(--line);padding:12px 0}details.topic summary{cursor:pointer;font-weight:800}
.problem-list{display:grid;grid-template-columns:repeat(3,1fr);gap:8px;margin-top:10px}
.problem{border:1px solid var(--line);border-radius:10px;padding:10px;background:#fff;font-size:12px}.problem em{display:block;font-style:normal;color:var(--muted);font-size:11px}
.checklist{columns:2;column-gap:28px}.checklist .task{break-inside:avoid}
.page-links{display:grid;grid-template-columns:repeat(3,1fr);gap:14px}
.page-link{display:block;padding:20px;border:1px solid var(--line);border-radius:16px;background:#fff;box-shadow:var(--shadow);color:var(--ink)}
.page-link:hover{text-decoration:none;transform:translateY(-1px)}
.page-link strong{display:block;font-size:18px;margin-bottom:6px}.page-link span{font-size:13px;color:var(--muted)}
.course-intro{display:grid;grid-template-columns:1fr 280px;gap:30px;align-items:end;background:var(--surface);border:1px solid var(--line);border-radius:16px;padding:22px;margin-bottom:18px;box-shadow:var(--shadow)}
.course-intro h2{margin-bottom:8px}.course-intro p{margin:0;color:var(--muted)}
.course-picker-wrap{display:grid;gap:6px}.course-picker-wrap label{font-size:12px;font-weight:800;color:var(--muted)}
.course-picker-wrap select{width:100%;border:1px solid var(--line);background:#fff;color:var(--ink);border-radius:10px;padding:10px 12px;font:inherit}
.course-list{display:grid;gap:14px}
details.course-card{background:var(--surface);border:1px solid var(--line);border-radius:16px;overflow:hidden;box-shadow:0 8px 22px rgba(24,33,47,.05);scroll-margin-top:72px}
.course-summary{cursor:pointer;list-style:none;padding:20px 20px 20px 52px;display:grid;grid-template-columns:1fr 150px;gap:22px;align-items:center;position:relative}
.course-summary::-webkit-details-marker{display:none}.course-summary::before{content:"＋";position:absolute;left:20px;top:50%;transform:translateY(-50%);color:var(--accent);font-size:20px;font-weight:900}.course-card[open]>.course-summary::before{content:"−"}
.course-summary-main{display:grid;gap:3px}.course-summary-main strong{font-size:19px}.course-summary-main>span:last-child{font-size:13px;color:var(--muted)}
.course-term{font-size:11px!important;text-transform:uppercase;letter-spacing:.08em;color:var(--accent)!important;font-weight:800}
.course-progress{display:grid;gap:7px;justify-items:end}.course-progress b{font-size:14px}
.mini-progress{display:block;width:150px;height:7px;background:#e8ebef;border-radius:99px;overflow:hidden}.mini-progress i{display:block;width:0;height:100%;background:var(--accent2);transition:.25s}
.course-body{padding:0 20px 22px;border-top:1px solid var(--line)}
.course-source{display:flex;gap:12px;align-items:center;justify-content:space-between;padding:14px 0;color:var(--muted);font-size:12px}.course-source a{font-weight:800}
.course-section{padding:14px 0 6px}.course-section+.course-section{border-top:1px solid var(--line)}.course-section h3{font-size:15px;margin-bottom:10px}
.course-items{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:8px}
.course-item{display:flex;align-items:flex-start;gap:10px;border:1px solid #e5e9ee;background:#fbfcfd;border-radius:11px;padding:11px 12px;min-width:0}
.course-item input{margin-top:4px;accent-color:var(--accent);flex:none}.course-item-copy{min-width:0}.course-item-copy>label{display:block;font-size:13px;font-weight:750;line-height:1.4;cursor:pointer}
.course-item-meta{display:flex;align-items:center;gap:7px;flex-wrap:wrap;margin-top:5px;color:var(--muted);font-size:10px}.course-item-meta a{font-weight:750;font-size:11px}
.content-type,.linked-week{display:inline-flex;border-radius:999px;padding:2px 6px;background:#edf0f3;color:#4d5a68;font-weight:750}.linked-week{background:#e3f4ef;color:#176455}
footer{padding:34px 0 60px;color:var(--muted);font-size:12px}
@media (max-width:850px){
 .span4,.span6,.span8,.span12{grid-column:span 12}
 .trackgrid,.problem-list,.page-links{grid-template-columns:1fr}
 details.week summary{grid-template-columns:72px 1fr}.weekdate{grid-column:2}.checklist{columns:1}
 .progress-head{align-items:flex-start;flex-direction:column}
 .course-intro{grid-template-columns:1fr}.course-summary{grid-template-columns:1fr}.course-progress{justify-items:start}.course-items{grid-template-columns:1fr}.course-source{align-items:flex-start;flex-direction:column}
}