/* ============================================================
   Excel course: mock-up styles (<xl-sheet>, <xl-ribbon>, <xl-chart>,
   dialogs, menus) + layouts shared by every deck.
   The mock-ups always stay light, like a screenshot, in both themes.
   ============================================================ */

:root{
  --xg:#107c41; --xg-deep:#0b5a2f; --xg-soft:#d6ebdf; --xg-fill:#e9f3ed;
  --xl-line:#d4d4d4; --xl-head:#f3f3f3; --xl-ink:#242424; --xl-muted:#616161;
  --xl-ui:"Segoe UI",system-ui,-apple-system,"Helvetica Neue",Arial,sans-serif;
  --xl-cell:"Aptos Narrow","Segoe UI",system-ui,Arial,sans-serif;
}

/* ---------- the window ---------- */
xl-sheet,xl-ribbon{display:inline-block;max-width:100%;vertical-align:top;line-height:1.2;text-align:left}
xl-sheet.block,xl-ribbon.block{display:block}
.xs{display:inline-flex;flex-direction:column;max-width:100%;font-family:var(--xl-ui);font-weight:400;font-size:13px;color:var(--xl-ink);background:#fff;border:1px solid #c6c6c6;border-radius:8px;overflow:hidden;box-shadow:0 10px 30px rgba(29,39,66,.14)}
.xs-ribonly{display:block}
.xs *{box-sizing:border-box}
.xs-title{display:flex;align-items:center;gap:10px;height:30px;padding:0 10px;background:var(--xg);color:#fff;font-size:12px;white-space:nowrap}
.xs-title .xi{opacity:.9}
.xs-autosave{display:flex;align-items:center;gap:6px}
.xs-autosave i{width:26px;height:14px;border-radius:7px;background:#fff;position:relative}
.xs-autosave i::after{content:"";position:absolute;right:2px;top:2px;width:10px;height:10px;border-radius:50%;background:var(--xg)}
.xs-autosave b{font-weight:600}
.xs-tname{margin-left:4px;font-weight:600}
.xs-search{margin-left:auto;margin-right:auto;display:flex;align-items:center;gap:6px;width:min(260px,30%);height:20px;padding:0 8px;border-radius:4px;background:rgba(255,255,255,.22);color:#f2f2f2}
.xs-user{width:22px;height:22px;border-radius:50%;background:#fff;color:var(--xg);display:grid;place-items:center}
.xs-win{letter-spacing:8px;opacity:.9}

/* ribbon */
.xs-rib{background:#fff;border-bottom:1px solid var(--xl-line)}
.xr-tabs{display:flex;align-items:flex-end;gap:2px;height:30px;padding:0 6px;background:#fff;border-bottom:1px solid var(--xl-line);white-space:nowrap;overflow:hidden}
.xr-tab{padding:5px 9px 6px;font-size:12.5px;color:var(--xl-ink);border-bottom:3px solid transparent;border-radius:3px 3px 0 0}
.xr-tab.file{color:#fff;background:var(--xg);border-radius:4px;padding:3px 12px;margin:0 4px 4px 0;font-weight:600}
.xr-tab.on{color:var(--xg);border-bottom-color:var(--xg);font-weight:600}
.xr-tab.ctx{background:#e2f0e8}
.xr-right{margin-left:auto;display:flex;align-items:center;gap:10px;padding-bottom:4px}
.xr-share{display:inline-flex;align-items:center;gap:4px;padding:3px 10px;border-radius:4px;background:var(--xg);color:#fff;font-size:11.5px;font-weight:600}
.xr-body{display:flex;align-items:stretch;height:92px;padding:4px 4px 2px;background:#f7f7f7;overflow:hidden;white-space:nowrap}
.xr-group{display:flex;flex-direction:column;padding:0 5px;border-right:1px solid #dcdcdc}
.xr-group:last-child{border-right:none}
.xr-items{flex:1;display:flex;gap:3px;align-items:flex-start}
.xr-col{display:flex;flex-direction:column;gap:1px}
.xr-big{display:flex;flex-direction:column;align-items:center;justify-content:flex-start;width:56px;min-height:60px;font-size:10px;line-height:1.1;text-align:center;padding:3px 2px;border-radius:3px;color:var(--xl-ink)}
.xr-big .xi{color:var(--xg);margin-bottom:3px;flex:none}
.xr-big span{white-space:normal}
.xr-sm{display:flex;align-items:center;gap:4px;font-size:10.5px;padding:1px 4px;border-radius:3px;height:19px;color:var(--xl-ink)}
.xr-sm .xi{color:var(--xg);flex:none}
.xr-box{display:inline-flex;justify-content:space-between;align-items:center;height:19px;border:1px solid #c8c8c8;background:#fff;font-size:10.5px;padding:0 5px;border-radius:2px;margin:1px 0;color:var(--xl-ink)}
.xr-box i{font-style:normal;color:#666;font-size:9px}
.xr-gname{font-size:10px;color:var(--xl-muted);text-align:center;margin-top:auto;padding-top:1px}
.xr-group.collapsed .xr-items,.xr-group.collapsed .xr-gname{display:none}
.xr-coll{width:62px;margin:4px 0 6px;flex:1;justify-content:center}
.xr-hl{outline:2.5px solid #f47629;outline-offset:1px;background:#fff1e3;border-radius:4px;animation:xr-pulse 1.4s ease-in-out infinite}
.xr-group.xr-hl{outline-offset:-2px}
@keyframes xr-pulse{50%{outline-color:#ffc23c}}

/* formula bar */
.xs-fbar{display:flex;align-items:center;height:28px;border-bottom:1px solid var(--xl-line);background:#fff;font-size:13px}
.xs-name{width:78px;height:100%;display:flex;align-items:center;padding:0 8px;border-right:1px solid var(--xl-line);font-family:var(--xl-cell);font-size:13px}
.xs-name::after{content:"▾";margin-left:auto;font-size:9px;color:#777}
.xs-fxb{display:flex;align-items:center;gap:8px;padding:0 10px;border-right:1px solid var(--xl-line);height:100%;color:#888;font-size:12px}
.xs-fxb i{font-style:italic;font-family:Georgia,serif;color:#444;font-size:14px}
.xs-fx{flex:1;padding:0 8px;font-family:var(--xl-cell);font-size:13.5px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}

/* grid */
.xs-gridwrap{position:relative;overflow:hidden;background:#fff}
.xs-t{border-collapse:separate;border-spacing:0;table-layout:fixed;font-family:var(--xl-cell);font-size:14px}
.xs-t th{height:21px;background:var(--xl-head);color:#444;font-weight:400;font-size:12px;text-align:center;border-right:1px solid var(--xl-line);border-bottom:1px solid var(--xl-line);padding:0;position:relative}
.xs-t th.xs-rh{height:24px;width:34px}
.xs-t th.on{background:var(--xg-soft);color:var(--xg);font-weight:600}
.xs-t th.xs-ch.on{box-shadow:inset 0 -2px 0 var(--xg)}
.xs-t th.xs-rh.on{box-shadow:inset -2px 0 0 var(--xg)}
.xs-corner i{position:absolute;right:3px;bottom:3px;border:6px solid transparent;border-right-color:#b5b5b5;border-bottom-color:#b5b5b5}
.xs-t td{height:24px;padding:0 4px;border-right:1px solid var(--xl-line);border-bottom:1px solid var(--xl-line);white-space:nowrap;overflow:hidden;text-overflow:clip;position:relative;vertical-align:middle;transition:opacity .35s,transform .35s,background .3s}
.xs-c.al-l{text-align:left} .xs-c.al-c{text-align:center} .xs-c.al-r{text-align:right}
.xs-c.b{font-weight:700} .xs-c.i{font-style:italic} .xs-c.u{text-decoration:underline} .xs-c.s{text-decoration:line-through}
.xs-c.w{white-space:normal;line-height:1.15;padding-top:2px;padding-bottom:2px}
.xs-c.h{font-weight:700;background:#f2f2f2;border-bottom:1px solid #9e9e9e}
.xs-c.hid{opacity:0;transform:scale(.85)}
.xs-c.pop:not(.hid){animation:xs-flash .9s ease}
@keyframes xs-flash{0%{background:#fff3cd}100%{background:inherit}}
.xs-c.sel{background:var(--xg-fill)}
.xs-c.active{box-shadow:inset 0 0 0 2px var(--xg);z-index:2}
.xs-c.sel.active{background:#fff}
.xs-c.corner::after{content:"";position:absolute;right:-3px;bottom:-3px;width:6px;height:6px;background:var(--xg);border:1px solid #fff;z-index:3}
.xs-c.hl{box-shadow:inset 0 0 0 2.5px #f47629;background:#fff1e3;animation:xs-hl 1.4s ease-in-out infinite;z-index:1}
@keyframes xs-hl{50%{box-shadow:inset 0 0 0 2.5px #ffc23c}}
.xs-c.ref{box-shadow:inset 0 0 0 2px var(--refc);background:color-mix(in srgb,var(--refc) 10%,#fff);z-index:1}
.xs-c.editing{overflow:visible;text-align:left;background:#fff;z-index:4}
.xs-edit{display:inline-flex;align-items:center;background:#fff;white-space:nowrap;padding-right:2px}
.xs-caret{display:inline-block;width:1.5px;height:16px;background:#222;margin-left:1px;animation:xs-caret 1s steps(2) infinite}
@keyframes xs-caret{50%{opacity:0}}
.xs-err{position:absolute;left:0;top:0;border:5px solid transparent;border-top-color:var(--xg);border-left-color:var(--xg)}
.xs-cm{position:absolute;right:0;top:0;border:5px solid transparent;border-top-color:#8e44ad;border-right-color:#8e44ad}
.xs-nt{position:absolute;right:0;top:0;border:5px solid transparent;border-top-color:#d13438;border-right-color:#d13438}
.xs-dd{position:absolute;right:-1px;top:2px;width:18px;height:19px;border:1px solid #b5b5b5;background:#fff;color:#444;font-size:11px;font-style:normal;display:grid;place-items:center;border-radius:2px}
.xs-c.hasbar{padding-right:4px}
.xs-bar{position:absolute;left:0;top:2px;bottom:2px;background:linear-gradient(90deg,#638ec6,#9dbbe0);border-radius:0 2px 2px 0;z-index:0}
.xs-c.hasbar span{position:relative;z-index:1}
.xs-ico{display:inline-block;vertical-align:middle;margin-right:5px}
.xs-spark{display:block;margin:0 auto}
.xs-chk{display:inline-block;vertical-align:middle;width:15px;height:15px;border:1.5px solid #555;border-radius:3px;background:#fff;margin-right:4px;position:relative}
.xs-chk.on{background:var(--xg);border-color:var(--xg)}
.xs-chk.on::after{content:"";position:absolute;left:4px;top:1px;width:4px;height:8px;border:solid #fff;border-width:0 2px 2px 0;transform:rotate(45deg)}
.xs-layer{position:absolute;inset:0;pointer-events:none}
.xs-tip{position:absolute;background:#fff;border:1px solid #c8c8c8;box-shadow:0 4px 12px rgba(0,0,0,.18);padding:3px 8px;font-size:12px;font-family:var(--xl-ui);white-space:nowrap;border-radius:3px;z-index:6;animation:a-fade .3s both}
.xs-cur{position:absolute;width:28px;height:28px;transform:translate(-50%,-50%);z-index:7;background-repeat:no-repeat;background-size:contain;filter:drop-shadow(0 1px 1px rgba(0,0,0,.4))}
.xs-cur-cross{background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 28 28'%3E%3Cpath d='M14 3v22M3 14h22' stroke='%23fff' stroke-width='7' stroke-linecap='round'/%3E%3Cpath d='M14 3v22M3 14h22' stroke='%23000' stroke-width='3.5' stroke-linecap='round'/%3E%3C/svg%3E")}
.xs-cur-fill{width:18px;height:18px;transform:translate(-30%,-30%);background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 18 18'%3E%3Cpath d='M9 2v14M2 9h14' stroke='%23000' stroke-width='2.4'/%3E%3C/svg%3E")}
.xs-cur-arrow{transform:translate(-20%,-10%);background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 28 28'%3E%3Cpath d='M6 3l15 13-6 1 4 7-3 1.5-4-7-5 4.5z' fill='%23fff' stroke='%23000' stroke-width='1.6' stroke-linejoin='round'/%3E%3C/svg%3E")}
.xs-cur-col{background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 28 28'%3E%3Cpath d='M14 4v20M4 14h20M8 10l-4 4 4 4M20 10l4 4-4 4' fill='none' stroke='%23fff' stroke-width='5' stroke-linecap='round' stroke-linejoin='round'/%3E%3Cpath d='M14 4v20M4 14h20M8 10l-4 4 4 4M20 10l4 4-4 4' fill='none' stroke='%23000' stroke-width='2.2' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E")}

/* sheet tabs + status bar */
.xs-sheets{display:flex;align-items:center;gap:2px;height:26px;padding:0 8px;background:#f3f3f3;border-top:1px solid var(--xl-line);font-size:12px}
.xs-arr{color:#888;margin-right:8px;letter-spacing:3px}
.xs-tab{padding:4px 14px;background:#f3f3f3;color:#444;border-right:1px solid #d4d4d4}
.xs-tab.on{background:#fff;color:var(--xg);font-weight:600;box-shadow:inset 0 -3px 0 var(--xg)}
.xs-addtab{margin-left:6px;width:18px;height:18px;border-radius:50%;border:1px solid #999;color:#444;display:grid;place-items:center;font-size:13px}
.xs-status{display:flex;align-items:center;gap:16px;height:22px;padding:0 10px;background:#f3f3f3;font-size:11px;color:#444;white-space:nowrap}
.xs-stats{margin-left:auto}
.xs-views{display:flex;gap:6px;color:#555}
.xs-zoom{color:#555}

/* ---------- Excel-like dialog boxes (hand-written HTML) ---------- */
.xd{display:inline-block;font-family:var(--xl-ui);font-size:13px;color:var(--xl-ink);background:#fff;border:1px solid #9a9a9a;border-radius:8px;box-shadow:0 18px 44px rgba(0,0,0,.28);overflow:hidden;min-width:300px;text-align:left;font-weight:400}
.xd-title{display:flex;align-items:center;height:30px;padding:0 10px 0 12px;background:#fff;border-bottom:1px solid var(--xl-line);font-weight:600}
.xd-title::after{content:"?  ✕";margin-left:auto;color:#555;letter-spacing:4px;font-weight:400}
.xd-tabs{display:flex;gap:2px;padding:6px 10px 0;border-bottom:1px solid var(--xl-line)}
.xd-tabs span{padding:4px 10px;border:1px solid transparent;border-bottom:none;border-radius:4px 4px 0 0;color:#444}
.xd-tabs span.on{border-color:var(--xl-line);background:#fff;margin-bottom:-1px;font-weight:600;color:var(--xl-ink)}
.xd-body{padding:12px 14px}
.xd-row{display:grid;grid-template-columns:110px 1fr;align-items:center;gap:8px;margin:5px 0}
.xd-row.full{grid-template-columns:1fr}
.xd-lbl{color:#333}
.xd-in,.xd-sel{display:flex;align-items:center;height:24px;padding:0 6px;border:1px solid #8a8a8a;border-radius:2px;background:#fff;font-family:var(--xl-cell);font-size:13px;white-space:nowrap;overflow:hidden}
.xd-sel::after{content:"▾";margin-left:auto;font-size:10px;color:#555}
.xd-in.focus,.xd-sel.focus{border-color:var(--xg);box-shadow:0 0 0 1px var(--xg)}
.xd-chk,.xd-rad{display:inline-flex;align-items:center;gap:6px;margin-right:12px;color:#333}
.xd-chk::before{content:"";width:14px;height:14px;border:1.5px solid #555;border-radius:2px;background:#fff}
.xd-chk.on::before{background:var(--xg);border-color:var(--xg);box-shadow:inset 0 0 0 2px #fff}
.xd-rad::before{content:"";width:14px;height:14px;border:1.5px solid #555;border-radius:50%;background:#fff}
.xd-rad.on::before{border:4px solid var(--xg)}
.xd-list{border:1px solid #8a8a8a;background:#fff;max-height:130px;overflow:hidden;font-family:var(--xl-cell)}
.xd-list span{display:block;padding:2px 8px}
.xd-list span.on{background:var(--xg);color:#fff}
.xd-btns{display:flex;justify-content:flex-end;gap:8px;padding:10px 14px;border-top:1px solid var(--xl-line);background:#f7f7f7}
.xd-btn{min-width:80px;height:26px;display:inline-grid;place-items:center;padding:0 12px;border:1px solid #8a8a8a;border-radius:3px;background:#fff;font-size:12.5px}
.xd-btn.primary{background:var(--xg);border-color:var(--xg);color:#fff;font-weight:600}
.xd-note{font-size:12px;color:#555;margin-top:6px}
.xd .hl,.xm li.hl{outline:2.5px solid #f47629;outline-offset:2px;animation:xr-pulse 1.4s infinite;border-radius:3px}

/* ---------- menus (right-click / dropdowns) ---------- */
.xm{display:inline-block;list-style:none;margin:0;padding:4px 0;min-width:190px;font-family:var(--xl-ui);font-size:13px;font-weight:400;color:var(--xl-ink);background:#fff;border:1px solid #bdbdbd;border-radius:6px;box-shadow:0 10px 28px rgba(0,0,0,.22);text-align:left}
.xm li{display:flex;align-items:center;gap:10px;padding:4px 14px 4px 10px;white-space:nowrap}
.xm li .xi{color:var(--xg);flex:none}
.xm li.sel{background:#e9f3ed}
.xm li.dis{color:#9a9a9a}
.xm li.sub::after{content:"▸";margin-left:auto;color:#666;padding-left:16px}
.xm li .k{margin-left:auto;padding-left:20px;color:#777;font-size:12px}
.xm hr{border:none;border-top:1px solid #e0e0e0;margin:4px 8px}
.xm li.head{font-weight:600;color:#555;font-size:11.5px;text-transform:uppercase;letter-spacing:.04em}

/* ---------- Backstage (File) view ---------- */
.xb{display:grid;grid-template-columns:150px 1fr;font-family:var(--xl-ui);font-weight:400;font-size:13px;color:var(--xl-ink);background:#fff;border:1px solid #c6c6c6;border-radius:8px;overflow:hidden;box-shadow:0 10px 30px rgba(29,39,66,.14);text-align:left}
.xb-nav{background:var(--xg);color:#fff;padding:14px 0}
.xb-nav span{display:flex;align-items:center;gap:10px;padding:4px 18px;font-size:12.5px}
.xb-nav span.on{background:rgba(255,255,255,.18)}
.xb-nav span.back{font-size:18px;padding-bottom:8px}
.xb-nav span.gap{margin-top:auto;border-top:1px solid rgba(255,255,255,.25)}
.xb-nav .xi{color:#fff}
.xb-main{padding:18px 22px}
.xb-main h3{font-family:var(--xl-ui);font-weight:600;font-size:22px;color:var(--xl-ink);margin:0 0 12px}
.xb-tiles{display:flex;gap:12px;flex-wrap:wrap}
.xb-tile{width:112px;text-align:center;font-size:11.5px}
.xb-tile i{display:block;height:80px;border:1px solid #d4d4d4;border-radius:4px;background:repeating-linear-gradient(0deg,#fff 0 11px,#eee 11px 12px),#fff;margin-bottom:6px;position:relative}
.xb-tile i.blank::after{content:"+";position:absolute;inset:0;display:grid;place-items:center;font-size:30px;color:var(--xg)}
.xb-recent{margin-top:14px;border-top:1px solid #e0e0e0}
.xb-recent div{display:grid;grid-template-columns:24px 1fr auto;gap:10px;padding:6px 4px;border-bottom:1px solid #f0f0f0;font-size:12.5px;align-items:center}
.xb-recent .xi{color:var(--xg)}
.xb-recent small{color:#777}

/* ---------- small bits ---------- */
kbd{display:inline-block;font-family:var(--xl-ui);font-weight:700;font-size:.78em;line-height:1;color:var(--ink);background:var(--surface);border:2px solid var(--line-2);border-bottom-width:4px;border-radius:7px;padding:5px 8px;margin:0 2px;vertical-align:middle;white-space:nowrap;box-shadow:var(--shadow-sm)}
kbd.big{font-size:22px;padding:8px 14px}
.keys{display:inline-flex;align-items:center;gap:4px}
.keys i{font-style:normal;color:var(--muted);font-weight:800}
.badge{display:inline-block;vertical-align:middle;font-family:var(--body);font-size:11px;font-weight:800;letter-spacing:.06em;text-transform:uppercase;padding:2px 9px;border-radius:var(--r-pill);margin-left:8px}
.badge-365{background:var(--xg);color:#fff}
.badge-new{background:var(--sun);color:#1d2742}
.badge-pro{background:var(--violet);color:#fff}
.ex-pill{display:inline-block;font-family:var(--display);font-weight:700;font-size:16px;background:var(--surface-2);border:2px solid var(--line);border-radius:var(--r-pill);padding:1px 12px}

/* function syntax + cards */
.fx{display:inline-block;font-family:ui-monospace,"Cascadia Code",Consolas,Menlo,monospace;font-size:19px;line-height:1.35;font-weight:600;background:var(--surface);border:2px solid var(--line);border-radius:12px;padding:5px 14px;color:var(--ink);white-space:nowrap}
.fx.sm{font-size:16px;padding:3px 10px}
.fx.lg{font-size:24px}
.fx.wrap{white-space:normal}
.fx b{color:var(--xg);font-weight:800} [data-theme="dark"] .fx b{color:#4cd38a}
.fx i{font-style:normal;color:var(--cta-deep)} [data-theme="dark"] .fx i{color:var(--cta)}
.fx .opt{color:var(--muted)} .fx .str{color:var(--violet)} .fx .n{color:var(--brand)}
.fn-head{display:flex;align-items:center;gap:18px;flex-wrap:wrap}
.fn-head .slide-title{margin-top:0;font-size:46px}
.fn-what{font-size:20px;line-height:1.4;margin-top:6px;max-width:980px}
.fn-what b{color:var(--ink)}
.fn-grid{flex:1;min-height:0;display:grid;grid-template-columns:1fr 1fr;gap:24px;margin-top:14px;align-items:start}
.fn-grid.l{grid-template-columns:1.25fr 1fr} .fn-grid.r{grid-template-columns:1fr 1.25fr}
.fn-grid.full{grid-template-columns:1fr}
.fn-args{list-style:none;display:flex;flex-direction:column;gap:7px}
.fn-args li{display:grid;grid-template-columns:auto 1fr;gap:12px;align-items:baseline;font-size:17px;line-height:1.3;background:var(--surface);border:2px solid var(--line);border-radius:12px;padding:6px 12px}
.fn-args code{font-family:ui-monospace,Consolas,monospace;font-weight:800;color:var(--cta-deep);font-size:16px}
[data-theme="dark"] .fn-args code{color:var(--cta)}
.fn-args .opt code{color:var(--muted)}
.fn-ex{display:flex;flex-direction:column;gap:8px}
.fn-ex .fx{align-self:flex-start}
.result{display:inline-flex;align-items:center;gap:10px;font-family:var(--display);font-weight:800;font-size:24px;color:var(--ink);background:color-mix(in srgb,var(--sun) 35%,transparent);border-radius:14px;padding:2px 16px}
.result span{font-size:16px;color:var(--ink-soft);font-weight:700}
.result.ok{background:color-mix(in srgb,var(--mint) 22%,transparent)}
.result.bad{background:color-mix(in srgb,var(--coral) 22%,transparent)}

/* demo layouts: mock-up + numbered steps */
.xl-demo{flex:1;min-height:0;display:grid;grid-template-columns:1fr 400px;gap:26px;align-items:start;margin-top:14px}
.xl-demo.n{grid-template-columns:1fr 340px} .xl-demo.w{grid-template-columns:1fr 460px}
.xl-demo.stack{grid-template-columns:1fr}
.xl-demo.rev{grid-template-columns:400px 1fr}
.xl-demo.rev > :first-child{order:2}
.howto{list-style:none;display:flex;flex-direction:column;gap:10px;margin:0}
.howto li{position:relative;display:block;background:var(--surface);border:2px solid var(--line);border-radius:16px;padding:10px 14px 10px 58px;font-family:var(--display);font-size:19px;font-weight:600;line-height:1.3;box-shadow:var(--shadow-sm)}
.howto li > i{position:absolute;left:12px;top:50%;margin-top:-16px;width:32px;height:32px;border-radius:50%;display:grid;place-items:center;font-style:normal;font-weight:800;font-size:16px;color:#fff;background:var(--cta)}
.howto li.try{border:2.5px dashed var(--violet);background:color-mix(in srgb,var(--violet) 8%,var(--surface))}
.howto li.try > i{background:var(--violet)}
.howto li.ok{border-color:var(--mint)} .howto li.ok > i{background:var(--mint)}
.howto li small{display:block;font-family:var(--body);font-size:14.5px;font-weight:600;color:var(--muted);margin-top:2px}
.howto code,.steps code,.note code,.tip code,.slide-sub code,.fn-what code,.lead code,.q-text code,.asg code,.cards code{font-family:ui-monospace,Consolas,monospace;font-size:.92em;font-weight:700;color:var(--xg);background:color-mix(in srgb,var(--xg) 10%,transparent);padding:0 6px;border-radius:6px}
[data-theme="dark"] .howto code,[data-theme="dark"] .steps code,[data-theme="dark"] .note code,[data-theme="dark"] .tip code,[data-theme="dark"] .slide-sub code,[data-theme="dark"] .fn-what code,[data-theme="dark"] .lead code,[data-theme="dark"] .q-text code,[data-theme="dark"] .asg code,[data-theme="dark"] .cards code{color:#4cd38a}
.howto.sm li{font-size:16.5px;padding:8px 12px 8px 52px}
.howto.sm li > i{width:28px;height:28px;margin-top:-14px;font-size:14px}

/* numbered callouts over a mock-up */
.shot{position:relative;display:inline-block;max-width:100%}
.pin{position:absolute;z-index:8;width:34px;height:34px;border-radius:50%;display:grid;place-items:center;font-family:var(--display);font-weight:800;font-size:17px;color:#fff;background:var(--cta);border:3px solid #fff;box-shadow:0 4px 12px rgba(0,0,0,.3);transform:translate(-50%,-50%)}
.pin.b{background:var(--brand)} .pin.m{background:var(--mint)} .pin.v{background:var(--violet)} .pin.c{background:var(--coral)}
.pin.pulse{animation:pin-pulse 1.4s ease-in-out infinite}
@keyframes pin-pulse{50%{transform:translate(-50%,-50%) scale(1.18)}}
.legend{list-style:none;display:flex;flex-direction:column;gap:8px}
.legend li{display:grid;grid-template-columns:34px 1fr;gap:12px;align-items:center;font-family:var(--display);font-size:18px;font-weight:600;line-height:1.25}
.legend li i{width:30px;height:30px;border-radius:50%;display:grid;place-items:center;font-style:normal;font-weight:800;font-size:15px;color:#fff;background:var(--cta)}
.legend li.b i{background:var(--brand)} .legend li.m i{background:var(--mint)} .legend li.v i{background:var(--violet)} .legend li.c i{background:var(--coral)}
.legend li small{display:block;font-family:var(--body);font-size:14px;color:var(--muted);font-weight:600}

/* generic cards / columns */
.two{flex:1;min-height:0;display:grid;grid-template-columns:1fr 1fr;gap:24px;margin-top:14px;align-items:start}
.cards{display:grid;grid-template-columns:repeat(3,1fr);gap:18px;margin-top:18px}
.cards.c2{grid-template-columns:1fr 1fr} .cards.c4{grid-template-columns:repeat(4,1fr)} .cards.c5{grid-template-columns:repeat(5,1fr)}
.cardx{--c:var(--brand);position:relative;padding:18px 18px 16px;border-top:6px solid var(--c)}
.cardx.cta{--c:var(--cta)} .cardx.mint{--c:var(--mint)} .cardx.violet{--c:var(--violet)} .cardx.coral{--c:var(--coral)} .cardx.sun{--c:var(--sun)} .cardx.green{--c:var(--xg)}
.cardx h3{font-size:24px;display:flex;align-items:center;gap:10px}
.cardx h3 .xi,.cardx h3 svg{color:var(--c);flex:none}
.cardx p{font-size:16px;line-height:1.35;margin-top:6px}
.cardx ul{list-style:none;margin-top:8px}
.cardx li{position:relative;padding:3px 0 3px 20px;font-size:16px;line-height:1.3;color:var(--ink-soft)}
.cardx li::before{content:"";position:absolute;left:2px;top:11px;width:9px;height:9px;border-radius:50%;background:var(--c)}
.cardx .big-ico{width:54px;height:54px;border-radius:14px;display:grid;place-items:center;background:color-mix(in srgb,var(--c) 14%,transparent);color:var(--c);margin-bottom:8px}
.note{margin-top:12px;font-family:var(--display);font-weight:600;font-size:18px;line-height:1.3;background:var(--surface);border:2.5px dashed var(--violet);border-radius:16px;padding:8px 16px}
.note.warn{border-color:var(--coral)} .note.ok{border-color:var(--mint)} .note.sm{font-size:16px}
.note-tag{display:inline-block;vertical-align:middle;margin:-3px 8px 0 0;font-family:var(--body);font-size:11px;font-weight:800;letter-spacing:.08em;text-transform:uppercase;color:#fff;background:var(--violet);padding:2px 10px;border-radius:var(--r-pill)}
.note.warn .note-tag{background:var(--coral)} .note.ok .note-tag{background:var(--mint)}

/* comparison tables */
.tbl{width:100%;border-collapse:separate;border-spacing:0;font-size:17px;background:var(--surface);border:2px solid var(--line);border-radius:16px;overflow:hidden}
.tbl th{font-family:var(--display);font-weight:800;font-size:17px;text-align:left;padding:9px 14px;background:color-mix(in srgb,var(--brand) 12%,var(--surface));border-bottom:2px solid var(--line)}
.tbl td{padding:7px 14px;border-bottom:1px solid var(--line);vertical-align:top;line-height:1.3;color:var(--ink-soft)}
.tbl tr:last-child td{border-bottom:none}
.tbl td:first-child{font-weight:800;color:var(--ink)}
.tbl code{font-family:ui-monospace,Consolas,monospace;font-weight:700;color:var(--xg);font-size:.95em}
[data-theme="dark"] .tbl code{color:#4cd38a}
.tbl.sm{font-size:15px} .tbl.sm th,.tbl.sm td{padding:5px 10px}
.tbl tr.hl td{background:color-mix(in srgb,var(--sun) 25%,transparent)}

/* assignments */
.asg-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:14px;margin-top:16px}
.asg{--c:var(--brand);position:relative;display:flex;flex-direction:column;gap:6px;padding:26px 14px 14px;border-top:6px solid var(--c)}
.asg.c2{--c:var(--mint)} .asg.c3{--c:var(--cta)} .asg.c4{--c:var(--violet)} .asg.c5{--c:var(--coral)}
.asg .n{position:absolute;top:-20px;left:14px;width:38px;height:38px;border-radius:50%;display:grid;place-items:center;background:var(--c);color:#fff;font-family:var(--display);font-weight:800;font-size:19px;box-shadow:var(--shadow-sm)}
.asg h3{font-size:21px;line-height:1.15}
.asg p{font-size:14.5px;line-height:1.3}
.asg .skills{display:flex;flex-wrap:wrap;gap:4px;margin-top:2px}
.asg .skills span{font-size:11.5px;font-weight:800;padding:1px 8px;border-radius:var(--r-pill);background:color-mix(in srgb,var(--c) 14%,transparent);color:var(--ink)}
.asg .meta{font-size:13px;color:var(--muted);font-weight:700}
.asg .dl{margin-top:auto;display:flex;flex-direction:column;gap:6px;padding-top:8px}
.asg .sb{height:32px;font-size:14px;width:100%}
.asg .sb.xl{background:var(--xg);color:#fff;box-shadow:0 6px 14px rgba(16,124,65,.28)}
.asg-one{flex:1;min-height:0;display:grid;grid-template-columns:1fr 1fr;gap:26px;margin-top:14px;align-items:start}
.asg-one .tasks{list-style:none;counter-reset:t;display:flex;flex-direction:column;gap:7px}
.asg-one .tasks li{position:relative;padding:7px 12px 7px 46px;background:var(--surface);border:2px solid var(--line);border-radius:12px;font-size:16.5px;line-height:1.3}
.asg-one .tasks li::before{counter-increment:t;content:counter(t);position:absolute;left:10px;top:8px;width:26px;height:26px;border-radius:50%;display:grid;place-items:center;background:var(--c,var(--brand));color:#fff;font-family:var(--display);font-weight:800;font-size:14px}
.asg-one .story{font-size:18px;line-height:1.4}
.asg-one .story b{color:var(--ink)}

/* keyboard diagram */
.kb{display:inline-grid;gap:6px;padding:14px;background:var(--surface);border:2px solid var(--line);border-radius:18px;box-shadow:var(--shadow)}
.kb-row{display:flex;gap:6px}
.kb kbd{margin:0;min-width:42px;text-align:center;font-size:15px;padding:9px 8px}
.kb kbd.w2{min-width:70px} .kb kbd.w3{min-width:100px} .kb kbd.w6{min-width:230px}
.kb kbd.on{background:var(--cta);color:#fff;border-color:var(--cta-deep);animation:loop-pulse 1.2s infinite}
.kb kbd.on2{background:var(--brand);color:#fff;border-color:var(--brand-deep)}

/* charts */
xl-chart{display:inline-block;vertical-align:top;background:#fff;border:1px solid #d9d9d9;border-radius:4px;padding:6px;box-shadow:0 6px 18px rgba(29,39,66,.12);max-width:100%}
xl-chart svg{display:block;font-family:var(--xl-ui)}
.xc-title{font-size:14px;fill:#595959;text-anchor:middle;font-weight:400}
.xc-grid{stroke:#d9d9d9;stroke-width:1}
.xc-axis{stroke:#bfbfbf;stroke-width:1}
.xc-ax{font-size:10.5px;fill:#595959;text-anchor:middle}
.xc-ax.end{text-anchor:end} .xc-ax.start{text-anchor:start}
.xc-lbl{font-size:10.5px;fill:#404040;text-anchor:middle}
.xc-lbl.white{fill:#fff;font-weight:600}
.xc-bar{transform-box:fill-box;transform-origin:bottom;transform:scaleY(0);transition:transform .8s cubic-bezier(.2,.8,.2,1) calc(var(--i,0) * 60ms)}
.bar .xc-bar{transform-origin:left;transform:scaleX(0)}
.slide.is-active .xc-bar{transform:scale(1)}
.xc-line{stroke-dasharray:1;stroke-dashoffset:1;transition:stroke-dashoffset 1.2s ease .2s}
.slide.is-active .xc-line{stroke-dashoffset:0}
.xc-dot{opacity:0;transition:opacity .3s calc(.3s + var(--i,0) * 120ms)}
.slide.is-active .xc-dot{opacity:1}
.xc-slice{transform-box:fill-box;transform-origin:center;animation:a-pop .6s cubic-bezier(.3,1.6,.5,1) calc(var(--i,0) * 90ms) both}
.xc-area{opacity:0;animation:a-fade 1s .3s both}
.chart-frame{display:inline-block;position:relative}
.chart-frame .handle{position:absolute;width:8px;height:8px;border:1px solid #888;background:#fff;border-radius:50%}

/* data-step reveals inside mock-ups shouldn't shift layout */
.slide [data-step].xs-float{position:absolute}

/* colour helpers for green (Excel) tone in the course */
.t-xg{color:var(--xg)} [data-theme="dark"] .t-xg{color:#4cd38a}
.tone-xg{--c:var(--xg);--cd:var(--xg-deep)} [data-theme="dark"] .tone-xg{--cd:#4cd38a}
.kicker.k-xg{color:var(--xg);background:color-mix(in srgb,var(--xg) 14%,transparent)} [data-theme="dark"] .kicker.k-xg{color:#4cd38a}
.btn-xg{background:var(--xg);color:#fff;box-shadow:0 16px 40px rgba(16,124,65,.3)}
.btn-xg:hover{transform:translateY(-3px)}

@media (prefers-reduced-motion:reduce){
  .xc-bar,.slide.is-active .xc-bar{transform:none;transition:none}
  .xc-line{stroke-dashoffset:0}.xc-dot{opacity:1}.xc-slice,.xc-area{animation:none;opacity:1}
}

/* ---------- text quizzes (longer questions than the maths decks) ---------- */
.quiz.text .q{display:flex;flex-direction:column;align-items:center;padding:16px 14px 14px}
.quiz.text .q-text{font-size:20px;line-height:1.3;margin:4px 0;text-wrap:balance}
.quiz.text .opts{flex-direction:column;width:100%;margin-top:auto;padding-top:10px;gap:6px}
.quiz.text .opts button{font-size:16.5px;padding:6px 8px;min-width:0;line-height:1.2}
.quiz.text.cols-3 .q-text{font-size:19px}
.quiz.text.cols-3 .opts button{font-size:15.5px}

/* ---------- title-slide art: a floating mini sheet + chart ---------- */
.title-art xl-sheet{position:absolute;left:0;top:40px;transform:rotate(-6deg);z-index:2;box-shadow:var(--shadow-lg)}
.title-art xl-chart{position:absolute;right:-10px;bottom:30px;transform:rotate(5deg);z-index:1}
.title-art .mavi-xl{z-index:3}

/* ---------- roadmap on the "meet" slide ---------- */
.road{display:grid;grid-template-columns:repeat(4,1fr);gap:14px;margin-top:18px}
.road div{--c:var(--brand);position:relative;background:var(--surface);border:2px solid var(--line);border-top:6px solid var(--c);border-radius:18px;padding:22px 14px 14px;text-align:center}
.road div:nth-child(2){--c:var(--mint)} .road div:nth-child(3){--c:var(--violet)} .road div:nth-child(4){--c:var(--coral)}
.road i{position:absolute;top:-18px;left:50%;margin-left:-16px;width:32px;height:32px;border-radius:50%;display:grid;place-items:center;font-style:normal;font-family:var(--display);font-weight:800;font-size:16px;color:#fff;background:var(--c)}
.road b{display:block;font-family:var(--display);font-size:22px}
.road span{display:block;font-size:14.5px;color:var(--muted);font-weight:700;line-height:1.3;margin-top:4px}

/* ---------- timeline (history slide) ---------- */
.tl{position:relative;display:grid;grid-template-columns:repeat(5,1fr);gap:14px;margin-top:40px}
.tl::before{content:"";position:absolute;left:4%;right:4%;top:-18px;height:6px;border-radius:3px;background:linear-gradient(90deg,var(--brand),var(--mint),var(--sun),var(--cta),var(--coral))}
.tl div{position:relative;background:var(--surface);border:2px solid var(--line);border-radius:18px;padding:16px 14px 14px;text-align:center}
.tl div::before{content:"";position:absolute;left:50%;top:-26px;width:16px;height:16px;margin-left:-8px;border-radius:50%;background:var(--c,var(--brand));border:4px solid var(--surface);box-shadow:var(--shadow-sm)}
.tl .yr{display:inline-block;font-weight:800;font-size:13px;letter-spacing:.06em;text-transform:uppercase;color:#fff;background:var(--c,var(--brand));padding:2px 12px;border-radius:var(--r-pill)}
.tl h3{font-size:22px;margin-top:8px}
.tl p{font-size:15px;line-height:1.3;margin-top:4px}

/* ---------- shortcuts grid ---------- */
.sc-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:12px;margin-top:18px}
.sc{display:flex;flex-direction:column;align-items:center;gap:8px;padding:14px 10px 12px;text-align:center}
.sc .keys kbd{font-size:17px;padding:7px 10px}
.sc b{font-family:var(--display);font-size:17px;line-height:1.15}
.sc span{font-size:13.5px;color:var(--muted);font-weight:700;line-height:1.25}

/* charts outside a slide deck (landing page) draw immediately */
xl-chart:not(.slide xl-chart) .xc-bar{transform:scale(1)}
xl-chart:not(.slide xl-chart) .xc-line{stroke-dashoffset:0}
xl-chart:not(.slide xl-chart) .xc-dot{opacity:1}

/* grid children may shrink below their content width (long syntax lines) */
.fn-grid > *,.xl-demo > *,.two > *,.cards > *{min-width:0}