Add the season 2 intro clip, with its credit

.gitattributes

@@ -0,0 +1 @@
+assets/season2-intro.mp4 filter=lfs diff=lfs merge=lfs -text

app.py

@@ -243,6 +243,16 @@ def logout():
     return r
 
 
+@app.get("/assets/{name}")
+def asset(name: str):
+    """Static files for the page. Names are matched against what is actually on disk, so
+    a crafted name cannot walk out of the directory."""
+    d = os.path.join(HERE, "assets")
+    if name not in set(os.listdir(d) if os.path.isdir(d) else []):
+        raise HTTPException(404, "not found")
+    return FileResponse(os.path.join(d, name))
+
+
 @app.get("/api/season")
 def season(request: Request):
     return seasons.public(seasons.get(request.query_params.get("season")))

assets/season2-intro.mp4

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:d7c030572da28908115be8fbdea9a9abb45e263bc8b60f44fb465e411cf00a46
+size 5885191

index.html

@@ -48,6 +48,12 @@
             border:1px solid var(--line);border-radius:20px;padding:4px 12px}
   .wts b{color:var(--accent)}
 
+  #intro{margin:0 0 16px;border-radius:14px;overflow:hidden;border:1px solid var(--line);
+         background:#0d1420;line-height:0;box-shadow:var(--shadow)}
+  #intro:empty{display:none;margin:0;border:0}
+  #intro video{width:100%;height:auto;display:block}
+  #intro .credit{line-height:1.5;font-size:11px;color:#8ea3c0;background:#0d1420;
+                 padding:7px 12px;text-align:right}
   #seasonbar{display:flex;gap:6px;margin-bottom:14px}
   #seasonbar button{border:1px solid var(--line);background:#fff;color:var(--muted);
                     font:inherit;font-size:12.5px;font-weight:700;padding:7px 14px;
@@ -340,6 +346,7 @@
     </div>
     <div id="authbar"></div>
     <div id="langnote"></div>
+    <div id="intro"></div>
     <div id="seasonbar"></div>
     <div id="cd"><span class="cdlab" id="cdlab"></span><span class="cdval" id="cdval">&nbsp;</span></div>
     <p class="eyebrow">Open Discovery Challenge</p>
@@ -511,6 +518,7 @@ const T = {
     },
     ov_pred:"예측치", ov_pf:"말라리아 효소", ov_hs:"사람 효소", ov_sel:"선택도",
     private_note:"제출자가 비공개를 선택했습니다", copy_smiles:"분자식 복사",
+    intro_credit:"영상 제작해주신 카카오톡 @리카 님에게 감사드립니다.",
     season_soon:"준비중", season_notopen:"이 시즌은 아직 접수를 받지 않습니다. 채점기 검증이 끝나면 공지와 함께 엽니다.",
     cd_label:"시즌 #1 마감까지", cd_day:"일", cd_over_label:"시즌 #1 마감",
     cd_over:"마감되었습니다", view_3d:"3D 입체 구조로 보기",
@@ -793,6 +801,30 @@ const submittedDate = e => {
   }).format(new Date(Number(e.submitted_at) * 1000));
 };
 
+// Seasons can carry an intro clip. It is written into the page only for the season it
+// belongs to - emptied rather than hidden - so a reader on another season never fetches
+// the file. Muted and inline because autoplay with sound is blocked everywhere; the clip
+// has no audio track, so nothing is lost.
+const SEASON_INTRO = {2: "assets/season2-intro.mp4"};
+
+function renderIntro(){
+  const src = SEASON_INTRO[SEASON], box = $("#intro");
+  // clearing the marker as well as the markup: leaving it set made a return to this
+  // season look like "already playing" and the slot stayed empty
+  if(!src){ box.innerHTML = ""; delete box.dataset.src; return; }
+  const cred = t().intro_credit || "";
+  if(box.dataset.src === src && box.querySelector("video")){
+    // the clip is already playing; only the wording can have changed, and rewriting the
+    // whole block would restart the video every time the language is switched
+    const c = box.querySelector(".credit");
+    if(c) c.textContent = cred;
+    return;
+  }
+  box.dataset.src = src;
+  box.innerHTML = `<video src="${src}" autoplay loop muted playsinline preload="metadata"></video>`
+    + (cred ? `<div class="credit">${cred}</div>` : "");
+}
+
 function renderSeasonBar(){
   if(!SEASONS) return;
   const d = t();
@@ -853,6 +885,7 @@ function applyLang(){
   }
   if(d.prize_amt) $("#prize_amt").firstChild.nodeValue = d.prize_amt + " ";
   renderSeasonBar();
+  renderIntro();
   renderAuth();
   tickCountdown();
   if(DATA) render();