/* Tutorial page (journey.html): one page, two states.
   Overview – level sections with a picture in the left gutter, quiet list rows, one primary button.
   Learning – the rows fly into a narrow left column (tutorial-catalog.js animates the move) and the
   lesson plays on the right. Layout switches in one frame; the script does all the motion.
   Selectors start with "#main .tut" so the page-wide "#main h2 / p / li" rules cannot override them.
   Colors come from monochrome.css tokens. */
#main .tut{--tut-purple:#7532d6;--tut-pick:color-mix(in srgb,var(--tut-purple) 10%,var(--bg));--tut-soft:color-mix(in srgb,var(--ink) 3.5%,var(--bg));--tut-hover:color-mix(in srgb,var(--ink) 4%,transparent);--tut-hair:color-mix(in srgb,var(--ink) 9%,var(--bg));max-width:880px;color:var(--ink);font-variant-numeric:tabular-nums;-webkit-font-smoothing:antialiased}
:root[data-theme=dark] #main .tut{--tut-purple:#b39cf7;--tut-pick:color-mix(in srgb,var(--tut-purple) 16%,var(--bg));--tut-soft:color-mix(in srgb,var(--ink) 7%,var(--bg));--tut-hover:color-mix(in srgb,var(--ink) 6%,transparent);--tut-hair:color-mix(in srgb,var(--ink) 14%,var(--bg))}
/* Beats "#main p / li" (1,1,1) but loses to every class rule below (1,2,0). */
#main div.tut :is(h1,h2,p,ul,li){margin:0}

/* Head */
#main .tut .tut-head{display:flex;flex-direction:column;align-items:center;gap:6px;margin:0 0 28px;text-align:center}
#main .tut .tut-head h1{margin:0;font-size:30px;font-weight:600;line-height:1.15;letter-spacing:-.025em}
#main .tut .tut-count{flex:none;margin:0;font-size:13px;color:var(--muted)}
#main .tut .tut-count b{font-weight:600;color:var(--ink)}

/* Continue card: words and the one button on the left, the moving picture on the right. */
#main .tut .tut-resume{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,400px);align-items:center;gap:16px;margin:0 0 48px;padding:24px 20px 24px 36px;border-radius:24px;background:var(--tut-soft);overflow:hidden}
#main .tut .tut-resume-copy{display:flex;flex-direction:column;align-items:flex-start;min-width:0}
#main .tut .tut-resume-title{margin:0;font-size:22px;font-weight:600;line-height:1.3;letter-spacing:-.015em}
#main .tut .tut-resume-meta{margin:6px 0 0;font-size:13px;color:var(--muted)}
#main .tut .tut-progress{align-self:stretch;max-width:280px;height:3px;margin:14px 0 0;overflow:hidden;border-radius:999px;background:var(--tut-hair)}
#main .tut .tut-progress i{display:block;height:100%;border-radius:inherit;background:var(--tut-purple)}
#main .tut .tut-resume .tut-primary{margin:22px 0 0}
#main .tut .tut-resume-art svg{display:block;width:100%;height:auto}
#main .tut .tut-primary{display:inline-flex;align-items:center;justify-content:center;gap:6px;height:40px;padding:0 20px;border:0;border-radius:999px;background:var(--button);color:var(--button-ink);font:inherit;font-size:14px;font-weight:600;text-decoration:none;white-space:nowrap;cursor:pointer;transition:opacity .15s ease}
#main .tut .tut-primary:hover{opacity:.82}

/* Level section: picture in the gutter, rows on the right. */
#main .tut .tut-level{display:grid;grid-template-columns:76px minmax(0,1fr);margin:0 0 40px;scroll-margin-top:16px}
#main .tut .tut-level-art{padding:2px 0 0}
#main .tut .tut-level-art svg{display:block;width:56px;height:56px}
#main .tut .tut-level-body{min-width:0}
#main .tut .tut-level-head{display:flex;align-items:baseline;gap:10px;margin:0 0 4px;padding:0 12px;transform-origin:0 0}
#main .tut .tut-level-code{font-size:13px;font-weight:600;color:var(--muted)}
#main .tut .tut-level-head h2{margin:0;font-size:17px;font-weight:600;line-height:1.4;letter-spacing:-.01em}
#main .tut .tut-tag{padding:1px 8px;border-radius:999px;background:var(--tut-hover);font-size:12px;line-height:1.6;color:var(--muted)}
#main .tut .tut-level-count{margin-left:auto;font-size:13px;color:var(--muted)}
#main .tut .tut-level-intro{margin:0 0 8px;padding:0 12px;font-size:13px;line-height:1.5;color:var(--muted)}
#main .tut .tut-level-note{margin:0 0 6px;padding:0 12px;font-size:13px;color:var(--muted)}

/* Lesson rows: the same row as the learning list, with room for a summary and the action. */
#main .tut .tut-list{margin:0;padding:0;list-style:none}
#main .tut .tut-row{position:relative}
#main .tut .tut-row+.tut-row::before{content:"";position:absolute;top:0;left:60px;right:12px;height:1px;background:var(--tut-hair)}
#main .tut .tut-link{display:grid;grid-template-columns:36px minmax(0,1fr) auto;align-items:center;gap:12px;min-height:44px;padding:10px 12px;border-radius:12px;color:inherit;text-decoration:none;transition:background-color .15s ease}
#main .tut a.tut-link:hover{background:var(--tut-hover)}
#main .tut .tut-row:has(a.tut-link:hover)::before,#main .tut .tut-row:has(a.tut-link:hover)+.tut-row::before{opacity:0}
#main .tut a.tut-link:focus-visible{outline:2px solid var(--ink);outline-offset:-2px}
#main .tut .tut-num{font-size:13px;color:var(--muted)}
#main .tut .tut-num svg{display:block;width:16px;height:16px;fill:none;stroke:var(--accent);stroke-width:2.2;stroke-linecap:round;stroke-linejoin:round}
#main .tut .tut-text{min-width:0}
#main .tut .tut-title{display:block;overflow:hidden;font-size:15px;font-weight:500;line-height:1.45;white-space:nowrap;text-overflow:ellipsis}
#main .tut .tut-desc{display:block;overflow:hidden;margin:1px 0 0;font-size:13px;line-height:1.5;color:var(--muted);white-space:nowrap;text-overflow:ellipsis}
#main .tut .tut-desc.is-now{color:var(--tut-purple)}
#main .tut .tut-meta{display:block;overflow:hidden;margin:2px 0 0;font-size:12px;line-height:1.5;color:color-mix(in srgb,var(--muted) 80%,var(--bg));white-space:nowrap;text-overflow:ellipsis}
#main .tut .tut-go{display:inline-flex;align-items:center;gap:2px;font-size:13px;font-weight:500;color:var(--muted);white-space:nowrap}
#main .tut .tut-go svg{width:16px;height:16px;fill:none;stroke:currentColor;stroke-width:2;stroke-linecap:round;stroke-linejoin:round}
#main .tut a.tut-link:hover .tut-go{color:var(--ink)}
#main .tut .is-coming .tut-title{color:var(--muted);font-weight:400}
#main .tut .tut-row.is-picked .tut-link{background:var(--tut-pick)}
#main .tut .tut-row.is-picked :is(.tut-title,.tut-num),#main .tut .tut-row.is-active :is(.tut-title,.tut-num){color:var(--tut-purple);font-weight:600}

#main .tut .tut-status{margin:0 0 16px;padding:10px 12px;border-radius:12px;background:color-mix(in srgb,#b45309 8%,var(--bg));font-size:13px;color:#b45309}
#main .tut .tut-status:empty{display:none}
#main .tut [aria-busy=true]{cursor:progress}
#main .tut .tut-primary[aria-busy=true],#main .tut [aria-busy=true] .tut-go{opacity:.5}
#main .tut .tut-row.is-target .tut-link{animation:tut-target 2.4s ease-out}
@keyframes tut-target{0%,40%{background:var(--tut-pick)}to{background:transparent}}
#main .tut .tut-foot{margin:4px 0 0;padding:0 12px 0 88px;font-size:13px;color:var(--muted)}
#main .tut .tut-foot a{color:var(--ink);text-underline-offset:3px}

/* Route strip: eight levels as connected nodes; done green, current purple, later grey. */
#main .tut .tut-route{margin:0 0 48px}
#main .tut .tut-route-label{margin:0 0 12px;padding:0 12px;font-size:13px;font-weight:600;color:var(--muted)}
/* The whole route sits in one long light grey pill; the current level is a solid purple dot. */
#main .tut .tut-route ol{display:grid;grid-template-columns:repeat(8,minmax(0,1fr));margin:0;padding:16px 16px 10px;list-style:none;border-radius:999px;background:var(--tut-soft)}
#main .tut .tut-node{position:relative;margin:0}
#main .tut .tut-node::before{content:"";position:absolute;top:17px;left:calc(-50% + 22px);right:calc(50% + 22px);height:2px;border-radius:2px;background:var(--tut-hair)}
#main .tut .tut-node:first-child::before{display:none}
#main .tut .tut-node.is-done::before,#main .tut .tut-node.is-now::before{background:var(--accent)}
#main .tut .tut-node a{display:grid;justify-items:center;gap:4px;padding:0 2px 6px;border-radius:12px;color:inherit;text-decoration:none;text-align:center}
#main .tut .tut-node a:hover .tut-dot{transform:scale(1.06)}
#main .tut .tut-node a:focus-visible{outline:2px solid var(--ink);outline-offset:2px}
#main .tut .tut-dot{display:grid;place-items:center;width:36px;height:36px;border:2px solid var(--tut-hair);border-radius:50%;background:var(--bg);font-size:13px;font-weight:600;color:var(--muted);transition:transform .15s ease}
#main .tut .tut-dot svg{width:16px;height:16px;fill:none;stroke:currentColor;stroke-width:2.6;stroke-linecap:round;stroke-linejoin:round}
#main .tut .is-done .tut-dot{border-color:var(--accent);background:var(--accent);color:var(--bg)}
#main .tut .is-now .tut-dot{border-color:var(--tut-purple);background:var(--tut-purple);color:#fff}
#main .tut .tut-node.is-coming .tut-dot{border-style:dashed}
#main .tut .tut-node-name{font-size:13px;font-weight:600;line-height:1.3}
#main .tut .tut-node.is-coming .tut-node-name{font-weight:400;color:var(--muted)}
#main .tut .tut-node-meta{font-size:12px;color:var(--muted)}

/* ===== Learning state ===== */
#main .tut.is-learning{max-width:1200px}
#main .tut .tut-bar{display:flex;align-items:center;justify-content:space-between;gap:12px}
#main .tut .tut-all{display:none;align-items:center;gap:4px;margin:0 0 12px;padding:6px 12px 6px 8px;border-radius:999px;font-size:13px;font-weight:600;color:var(--muted);text-decoration:none}
#main .tut.is-learning .tut-all{display:inline-flex;animation:tut-fade .3s ease .15s both}
#main .tut .tut-all:hover{background:var(--tut-hover);color:var(--ink)}
#main .tut .tut-all svg{width:16px;height:16px;fill:none;stroke:currentColor;stroke-width:2;stroke-linecap:round;stroke-linejoin:round}
@keyframes tut-fade{from{opacity:0}}
#main .tut .tut-shell{display:flex;align-items:flex-start}
#main .tut.is-learning .tut-shell{gap:28px}
#main .tut .tut-col{position:relative;flex:0 0 auto;width:100%;min-width:0}
#main .tut.is-learning .tut-col{position:sticky;top:0;width:280px;max-height:calc(100dvh - var(--header-height) - 110px);overflow:hidden auto;scrollbar-width:thin}
#main .tut .tut-col-list{position:relative;z-index:1}
#main .tut.is-learning.is-flying .tut-col{overflow:visible}
#main .tut .tut-player{flex:1 1 0;min-width:0}
#main .tut:not(.is-learning) .tut-player{display:none}
/* The pill behind the lesson being learned glides from row to row. */
#main .tut .tut-pill{position:absolute;z-index:0;border-radius:12px;background:var(--tut-pick);pointer-events:none;transition:top .45s cubic-bezier(.2,.85,.25,1),height .45s cubic-bezier(.2,.85,.25,1)}
#main .tut .tut-pill[hidden],#main .tut:not(.is-learning) .tut-pill{display:none}
#main .tut.is-learning .tut-row.is-active .tut-link{background:transparent}
/* Overview-only parts: fade before the switch, hidden while learning, fade back after. */
#main .tut :is(.tut-fold,.tut-level-art,.tut-tag,.tut-level-count,.tut-level-intro,.tut-level-note,.tut-desc,.tut-meta,.tut-go){transition:opacity .4s ease}
#main .tut.is-folding :is(.tut-fold,.tut-level-art,.tut-tag,.tut-level-count,.tut-level-intro,.tut-level-note,.tut-desc,.tut-meta,.tut-go){opacity:0;transition:opacity .15s ease}
#main .tut.is-unfolding :is(.tut-fold,.tut-level-art,.tut-tag,.tut-level-count,.tut-level-intro,.tut-level-note,.tut-desc,.tut-meta,.tut-go){opacity:0;transition:none}
#main .tut.is-learning :is(.tut-fold,.tut-level-art,.tut-tag,.tut-level-count,.tut-level-intro,.tut-level-note,.tut-desc,.tut-meta,.tut-go){display:none}
/* The narrow list. */
#main .tut.is-learning .tut-level{display:block;margin:0 0 14px}
#main .tut.is-learning .tut-level-head{margin:0 0 2px;padding:0 12px}
#main .tut.is-learning .tut-level-head h2{font-size:13px;color:var(--muted)}
#main .tut.is-learning .tut-level-code{font-size:12px}
#main .tut.is-learning .tut-link{grid-template-columns:36px minmax(0,1fr);min-height:42px;padding:9px 12px}
#main .tut.is-learning .tut-row+.tut-row::before{display:none}
#main .tut.is-learning .tut-row.is-active .tut-link{padding-right:72px}
/* 重学 sits beside the lesson being learned, like 继续 / 复习 in the overview. */
#main .tut .tut-redo{all:unset;display:none;position:absolute;top:50%;right:8px;transform:translateY(-50%);padding:4px 10px;border-radius:999px;font-size:12px;font-weight:600;color:var(--tut-purple);white-space:nowrap;cursor:pointer}
#main .tut.is-learning .tut-redo{display:inline-flex}
#main .tut .tut-redo:hover{background:color-mix(in srgb,var(--tut-purple) 14%,var(--bg))}
#main .tut .tut-redo:focus-visible{outline:2px solid var(--ink);outline-offset:2px}
#main .tut .tut-redo.is-confirm{background:#fff2ea;color:#c2410c}
:root[data-theme=dark] #main .tut .tut-redo.is-confirm{background:#2a160c;color:#ff9a62}
#main .tut .tut-redo-bar{position:static;transform:none}
#main .tut.is-learning .tut-redo-bar{display:none}

@media(max-width:760px){
 #main .tut.is-folding .tut-col{opacity:0;transform:translateX(-24px);transition:opacity .14s ease,transform .14s ease}
 #main .tut.is-learning .tut-col{display:none}
 #main .tut.is-learning .tut-redo-bar:not([hidden]){display:inline-flex;margin:0 0 12px}
 #main .tut.is-learning .tut-shell{gap:0}
}
@media(max-width:600px){
 #main .tut .tut-head{margin-bottom:20px}
 #main .tut .tut-head h1{font-size:28px}
 #main .tut .tut-resume{grid-template-columns:1fr;gap:4px;padding:8px 20px 22px;margin-bottom:36px}
 #main .tut .tut-resume-art{order:-1;margin:0 -8px}
 #main .tut .tut-resume .tut-primary{align-self:stretch}
 #main .tut .tut-route{margin-bottom:36px;overflow-x:auto;scrollbar-width:none}
 #main .tut .tut-route ol{grid-template-columns:repeat(8,72px);width:max-content}
 #main .tut .tut-route-label{position:sticky;left:0;width:max-content;padding:0 8px}
 /* Phone: the picture sits beside the level name; the rows get the full width. */
 #main .tut .tut-level{grid-template-columns:44px minmax(0,1fr);column-gap:12px;margin-bottom:32px}
 #main .tut .tut-level-body{display:contents}
 #main .tut .tut-level-art{grid-row:1/span 2;padding:0}
 #main .tut .tut-level-art svg{width:44px;height:44px}
 #main .tut :is(.tut-level-head,.tut-level-intro,.tut-level-note){grid-column:2;padding:0}
 #main .tut .tut-level-head{align-self:end;margin:0 0 2px}
 #main .tut .tut-level-intro{align-self:start}
 #main .tut .tut-list{grid-column:1/-1;margin-top:6px}
 #main .tut .tut-link{grid-template-columns:30px minmax(0,1fr) auto;gap:8px;padding:10px 8px}
 #main .tut .tut-row+.tut-row::before{left:46px;right:8px}
}
@media(prefers-reduced-motion:reduce){#main .tut,#main .tut *{transition:none!important;animation:none!important}}

/* Keep the lesson column aligned; let the route scroll at the panel edges. */
@media(max-width:600px){
 #main .tut .tut-route{box-sizing:border-box;width:calc(100% + 66px);margin-inline:-33px;padding-inline:33px}
 #main .tut .tut-route::-webkit-scrollbar{display:none}
}

/* Lesson gate (off unless switched on): 会员 after a member lesson's title; a lock where it is closed to you. */
#main .tut .tut-member{display:inline-block;margin-left:8px;padding:1px 8px;border-radius:999px;background:var(--tut-soft);font-size:12px;font-weight:600;line-height:1.5;color:var(--muted);vertical-align:2px}
#main .tut .tut-go.is-lock svg:first-child{width:13px;height:13px;margin-right:3px}