/* MIXXIN Vibe Coder 入門課 — shared stylesheet */
:root{
  --navy:#15304F; --navy-soft:#24456A; --ink:#15304F;
  --bg:#FFFFFF; --bg-tint:#F6F7FA;
  --surface-dark:#15304F; --on-dark:#FFFFFF;
  --yellow:#F5B947; --yellow-soft:#FCE3A4;
  --cyan:#7FC8D9; --lime:#D5E89A;
  --ink-60:rgba(21,48,79,.60); --ink-40:rgba(21,48,79,.40);
  --ink-20:rgba(21,48,79,.20); --ink-10:rgba(21,48,79,.10); --ink-05:rgba(21,48,79,.05);
  --hairline:rgba(21,48,79,.14);
  --success:#1B9A5A; --danger:#D92D20;
  --font-display:"Montserrat","Noto Sans TC",-apple-system,sans-serif;
  --font-body:"Noto Sans TC","Montserrat",-apple-system,sans-serif;
  --font-mono:"JetBrains Mono",ui-monospace,monospace;
}
.theme-dark{
  --bg:#0A1428; --bg-tint:#0F1D38; --ink:#FFFFFF;
  --ink-60:rgba(255,255,255,.70); --ink-40:rgba(255,255,255,.50);
  --ink-20:rgba(255,255,255,.24); --ink-10:rgba(255,255,255,.12); --ink-05:rgba(255,255,255,.06);
  --hairline:rgba(255,255,255,.16); --navy:#FFFFFF; --surface-dark:#0F1D38;
}
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0;}
html{scroll-behavior:smooth;}
body{
  font-family:var(--font-body); background:var(--bg); color:var(--ink);
  font-feature-settings:"palt"; -webkit-font-smoothing:antialiased;
  line-height:1.7; transition:background .3s,color .3s;
}

/* ---------- progress rail (top) ---------- */
.progress-track{position:fixed;top:0;left:0;right:0;height:4px;background:var(--ink-10);z-index:60;}
.progress-fill{height:100%;width:0;background:var(--yellow);transition:width .1s linear;}

/* ---------- brand header ---------- */
.header{
  position:sticky;top:0;z-index:50;background:var(--bg);
  border-bottom:1px solid var(--hairline);
  display:flex;align-items:center;justify-content:space-between;
  padding:14px 40px; gap:20px;
}
.brand{display:flex;align-items:center;gap:10px;text-decoration:none;}
.brand .dot{width:8px;height:8px;background:var(--yellow);}
.brand .name{font-family:var(--font-display);font-weight:900;font-size:14px;letter-spacing:.32em;color:var(--navy);}
.brand .sub{font-family:var(--font-display);font-weight:700;font-size:10px;letter-spacing:.24em;text-transform:uppercase;color:var(--ink-40);border-left:1px solid var(--hairline);padding-left:10px;}
.header-tools{display:flex;align-items:center;gap:8px;}
.btn-icon{background:none;border:1px solid var(--hairline);width:34px;height:34px;cursor:pointer;color:var(--ink);display:flex;align-items:center;justify-content:center;font-size:15px;transition:border-color .14s;}
.btn-icon:hover{border-color:var(--navy);}
.lesson-tag{font-family:var(--font-display);font-weight:800;font-size:10px;letter-spacing:.2em;text-transform:uppercase;background:var(--surface-dark);color:var(--on-dark);padding:6px 10px;white-space:nowrap;}
.lesson-nav-link{font-family:var(--font-display);font-weight:700;font-size:10px;letter-spacing:.14em;text-transform:uppercase;color:var(--ink-60);text-decoration:none;border:1px solid var(--hairline);padding:8px 12px;transition:all .14s;white-space:nowrap;}
.lesson-nav-link:hover{border-color:var(--navy);color:var(--navy);}

/* ---------- layout ---------- */
.layout{max-width:1200px;margin:0 auto;display:grid;grid-template-columns:220px 1fr;gap:0;}
@media(max-width:900px){.layout{grid-template-columns:1fr;}}

/* ---------- side nav ---------- */
.sidenav{position:sticky;top:63px;align-self:start;height:calc(100vh - 63px);padding:32px 20px 32px 40px;overflow-y:auto;border-right:1px solid var(--hairline);}
@media(max-width:900px){.sidenav{display:none;}}
.sidenav .eyebrow{font-family:var(--font-display);font-weight:700;font-size:11px;letter-spacing:.24em;text-transform:uppercase;color:var(--ink-40);margin-bottom:16px;}
.nav-item{display:flex;gap:10px;align-items:baseline;padding:8px 0;cursor:pointer;border:none;background:none;text-align:left;width:100%;color:var(--ink-60);transition:color .14s;font-family:var(--font-body);}
.nav-item:hover{color:var(--navy);}
.nav-item .n{font-family:var(--font-display);font-weight:900;font-size:12px;color:var(--ink-20);font-variant-numeric:tabular-nums;transition:color .14s;flex-shrink:0;}
.nav-item .t{font-size:13px;font-weight:500;line-height:1.4;}
.nav-item.active{color:var(--navy);}
.nav-item.active .n{color:var(--yellow);}
.nav-time{margin-top:24px;padding-top:16px;border-top:1px solid var(--hairline);font-family:var(--font-mono);font-size:11px;color:var(--ink-40);}

/* ---------- main ---------- */
main{padding:32px 40px 120px;min-width:0;}
@media(max-width:900px){main{padding:24px 20px 80px;}}

/* hero */
.hero{padding:24px 0 8px;border-bottom:1px solid var(--hairline);margin-bottom:8px;}
.hero .eyebrow{font-family:var(--font-display);font-weight:700;font-size:13px;letter-spacing:.28em;text-transform:uppercase;color:var(--ink-40);}
.hero h1{font-family:var(--font-display);font-weight:300;font-size:clamp(30px,5vw,52px);letter-spacing:.02em;color:var(--navy);margin:14px 0 6px;line-height:1.15;}
.hero .lead{font-size:15px;color:var(--ink-60);max-width:60ch;}
.hero-meta{display:flex;flex-wrap:wrap;gap:8px;margin-top:18px;}
.chip{font-family:var(--font-display);font-weight:700;font-size:11px;letter-spacing:.14em;text-transform:uppercase;padding:6px 12px;border:1px solid var(--hairline);color:var(--ink-60);}
.chip.solid{background:var(--yellow);color:#15304F;border-color:var(--yellow);}
.chip.dark{background:var(--surface-dark);color:var(--on-dark);border-color:var(--surface-dark);}

/* section */
.section{padding:52px 0 8px;scroll-margin-top:80px;}
.sec-head{display:flex;align-items:center;gap:16px;margin-bottom:28px;}
.sec-head .num{font-family:var(--font-display);font-weight:900;font-size:22px;color:var(--yellow);font-variant-numeric:tabular-nums;}
.sec-head .h{font-family:var(--font-display);font-weight:500;font-size:clamp(22px,3vw,28px);color:var(--navy);letter-spacing:-.01em;}
.sec-head .sub{font-size:12px;color:var(--ink-40);font-family:var(--font-mono);}
.sec-head .rule{flex:1;height:1px;background:var(--hairline);}
@media(max-width:560px){.sec-head .rule{display:none;}}

/* concept cards */
.concept{border:1px solid var(--hairline);padding:22px 24px;margin-bottom:16px;position:relative;}
.concept .k{font-family:var(--font-display);font-weight:800;font-size:12px;letter-spacing:.14em;text-transform:uppercase;color:var(--navy);display:flex;align-items:center;gap:8px;margin-bottom:10px;}
.concept .k .kn{width:22px;height:22px;background:var(--yellow);color:#15304F;display:flex;align-items:center;justify-content:center;font-size:12px;font-weight:900;flex-shrink:0;}
.concept p{font-size:14.5px;color:var(--ink-60);}
.concept p strong{color:var(--navy);font-weight:700;}

/* analogy row: layer cards */
.layers{display:grid;grid-template-columns:repeat(3,1fr);gap:12px;margin:8px 0 20px;}
.layers.two{grid-template-columns:repeat(2,1fr);}
@media(max-width:640px){.layers,.layers.two{grid-template-columns:1fr;}}
.layer{border:1px solid var(--hairline);padding:18px;background:var(--bg-tint);}
.layer .tag{font-family:var(--font-display);font-weight:900;font-size:13px;letter-spacing:.1em;color:var(--yellow);}
.layer .role{font-family:var(--font-display);font-weight:800;font-size:16px;color:var(--navy);margin:6px 0 8px;}
.layer .desc{font-size:13px;color:var(--ink-60);}

/* timeline table */
.flowtable{width:100%;border-collapse:collapse;margin:8px 0 16px;}
.flowtable td{padding:10px 12px;border-bottom:1px solid var(--hairline);font-size:14px;color:var(--ink-60);vertical-align:top;}
.flowtable td:first-child{font-family:var(--font-mono);font-size:12px;color:var(--navy);white-space:nowrap;width:96px;font-weight:500;}
.flowtable td b{color:var(--navy);font-weight:600;}
.flowtable tr.hi td{background:var(--yellow-soft);}
.theme-dark .flowtable tr.hi td{background:rgba(245,185,71,.12);}

/* prompt block */
.prompt{margin-bottom:16px;border:1px solid var(--hairline);}
.prompt-head{display:flex;align-items:center;justify-content:space-between;gap:12px;background:var(--surface-dark);padding:11px 16px;}
.prompt-head .label{font-family:var(--font-display);font-weight:800;font-size:11px;letter-spacing:.14em;text-transform:uppercase;color:var(--on-dark);}
.prompt-head .label .badge{background:var(--yellow);color:#15304F;padding:2px 7px;margin-right:8px;font-size:10px;}
.copy-btn{background:none;border:1px solid rgba(255,255,255,.3);color:var(--on-dark);font-family:var(--font-display);font-weight:700;font-size:10px;letter-spacing:.12em;text-transform:uppercase;padding:5px 10px;cursor:pointer;transition:all .14s;}
.copy-btn:hover{background:var(--yellow);color:#15304F;border-color:var(--yellow);}
.copy-btn.done{background:var(--lime);color:#15304F;border-color:var(--lime);}
.prompt pre{font-family:var(--font-mono);font-size:13px;line-height:1.7;color:var(--ink);padding:16px;white-space:pre-wrap;word-break:break-word;background:var(--bg);}

/* checklist */
.check{list-style:none;}
.check li{display:flex;gap:12px;align-items:flex-start;padding:12px 0;border-bottom:1px solid var(--hairline);cursor:pointer;}
.check li .box{flex-shrink:0;width:20px;height:20px;border:2px solid var(--ink-20);display:flex;align-items:center;justify-content:center;transition:all .15s;margin-top:1px;}
.check li .box svg{width:12px;height:12px;opacity:0;transition:opacity .15s;}
.check li.checked .box{background:var(--success);border-color:var(--success);}
.check li.checked .box svg{opacity:1;}
.check li .txt{font-size:14.5px;color:var(--ink-60);transition:color .15s;}
.check li.checked .txt{color:var(--ink-40);text-decoration:line-through;}

/* callout */
.callout{border-left:6px solid var(--yellow);background:var(--yellow-soft);padding:16px 20px;margin:16px 0;font-size:14px;color:#15304F;}
.theme-dark .callout{background:rgba(245,185,71,.12);color:var(--ink);}
.callout b{font-weight:800;}
.callout.danger{border-left-color:var(--danger);background:rgba(217,45,32,.07);}

/* dod banner */
.dod{background:var(--surface-dark);color:var(--on-dark);padding:24px 28px;margin:8px 0 4px;display:grid;grid-template-columns:auto 1fr;gap:20px;align-items:center;}
@media(max-width:560px){.dod{grid-template-columns:1fr;}}
.dod .big{font-family:var(--font-display);font-weight:900;font-size:40px;color:var(--yellow);font-variant-numeric:tabular-nums;line-height:1;}
.dod .lab{font-family:var(--font-display);font-weight:700;font-size:11px;letter-spacing:.2em;text-transform:uppercase;color:rgba(255,255,255,.55);margin-bottom:8px;}
.dod .txt{font-size:14.5px;color:rgba(255,255,255,.9);}
.dod .txt b{color:var(--yellow);font-weight:700;}

/* footer */
footer{max-width:1200px;margin:80px auto 0;padding:32px 40px;border-top:1px solid var(--hairline);display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:12px;}
footer .brand .name{font-size:12px;}
footer .ver{font-family:var(--font-mono);font-size:11px;color:var(--ink-40);}
.foot-nav{display:flex;gap:8px;flex-wrap:wrap;}

.body-p{font-size:14.5px;color:var(--ink-60);margin-bottom:12px;}
.body-p strong{color:var(--navy);font-weight:700;}
.mini-label{font-family:var(--font-display);font-weight:700;font-size:11px;letter-spacing:.2em;text-transform:uppercase;color:var(--ink-40);margin:20px 0 4px;}

/* ---------- figures ---------- */
figure{margin:18px 0 8px;border:1px solid var(--hairline);background:var(--bg-tint);overflow:hidden;}
figure.photo img{display:block;width:100%;height:220px;object-fit:cover;filter:saturate(.92);}
@media(max-width:560px){figure.photo img{height:170px;}}
figure .svg-wrap{padding:24px;background:var(--bg);}
figure svg{display:block;width:100%;height:auto;}
figcaption{display:flex;gap:10px;align-items:baseline;padding:10px 16px;border-top:1px solid var(--hairline);font-size:12.5px;color:var(--ink-60);}
figcaption .fnum{font-family:var(--font-display);font-weight:900;font-size:11px;letter-spacing:.1em;color:var(--yellow);flex-shrink:0;}
figcaption b{color:var(--navy);font-weight:700;}
figcaption .credit{margin-left:auto;font-family:var(--font-mono);font-size:10px;color:var(--ink-40);flex-shrink:0;padding-left:10px;}

/* photo placeholder (image handoff) */
figure.photo .ph{
  display:flex;flex-direction:column;align-items:center;justify-content:center;gap:8px;
  height:220px;background:
    repeating-linear-gradient(45deg, var(--ink-05), var(--ink-05) 12px, transparent 12px, transparent 24px);
  border-bottom:0;position:relative;
}
@media(max-width:560px){figure.photo .ph{height:170px;}}
figure.photo .ph .ph-tag{font-family:var(--font-display);font-weight:800;font-size:10px;letter-spacing:.2em;text-transform:uppercase;background:var(--surface-dark);color:var(--on-dark);padding:5px 10px;}
figure.photo .ph .ph-name{font-family:var(--font-mono);font-size:12px;color:var(--navy);font-weight:500;}
figure.photo .ph .ph-desc{font-size:12px;color:var(--ink-60);max-width:46ch;text-align:center;padding:0 20px;}
figure.photo .ph::after{content:"";position:absolute;inset:10px;border:2px dashed var(--ink-20);pointer-events:none;}

/* svg concept diagram helpers driven by CSS vars so dark mode adapts */
.dg-stroke{stroke:var(--navy);}
.dg-fill-navy{fill:var(--navy);}
.dg-fill-realnavy{fill:#15304F;}
.dg-fill-yellow{fill:var(--yellow);}
.dg-fill-soft{fill:var(--yellow-soft);}
.dg-fill-tint{fill:var(--bg-tint);}
.dg-fill-bg{fill:var(--bg);}
.dg-fill-cyan{fill:var(--cyan);}
.dg-fill-lime{fill:var(--lime);}
.dg-fill-danger{fill:var(--danger);}
.dg-text{fill:var(--navy);font-family:var(--font-display);font-weight:800;}
.dg-text-soft{fill:var(--ink-60);font-family:var(--font-body);}
.dg-mono{fill:var(--ink-60);font-family:var(--font-mono);}
.dg-on-dark{fill:#fff;font-family:var(--font-display);font-weight:800;}
.dg-on-dark-soft{fill:rgba(255,255,255,.65);font-family:var(--font-body);}
.dg-hair{stroke:var(--hairline);}
.dg-dash{stroke-dasharray:6 5;}

/* index page cards */
.lesson-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(300px,1fr));gap:16px;margin-top:8px;}
.lesson-card{border:1px solid var(--hairline);padding:22px;text-decoration:none;display:block;transition:border-color .14s;position:relative;background:var(--bg);}
.lesson-card:hover{border-color:var(--navy);}
.lesson-card .lc-num{font-family:var(--font-display);font-weight:900;font-size:22px;color:var(--yellow);font-variant-numeric:tabular-nums;}
.lesson-card .lc-title{font-family:var(--font-display);font-weight:700;font-size:16px;color:var(--navy);margin:8px 0 6px;line-height:1.4;}
.lesson-card .lc-out{font-size:13px;color:var(--ink-60);}
.lesson-card .lc-wow{margin-top:12px;padding-top:12px;border-top:1px solid var(--hairline);font-size:12px;color:var(--ink-60);}
.lesson-card .lc-wow b{color:var(--navy);font-weight:700;font-family:var(--font-display);font-size:10px;letter-spacing:.18em;text-transform:uppercase;margin-right:6px;}