/* Week 6（TEST）：整頁是一個場景，畫在 #rift（assets/rift.js），文字和按鈕疊在上面。
   不管網站是淺色還是深色主題，這一頁都是深空，所以顏色直接寫死，不用主題變數。 */
body.exam {
  --void: #04060c;
  --rift: #3aa0ff;
  --txt: #f1efe9;
  --txt-2: #c3cbe0;
  --txt-3: #8a93a8;
  background: var(--void);
  color: var(--txt);
  overflow: hidden;
  height: 100svh;
}
#rift, #bh { position: fixed; inset: 0; width: 100%; height: 100%; display: block; z-index: 1; }
/* 音效開關（assets/exam-sound.js） */
.sound-btn .i-off { display: none; }
.sound-btn.is-off .i-on { display: none; }
.sound-btn.is-off .i-off { display: block; }
/* 剛打開、那張圖還沒畫上去時：先用 CSS 把同一張圖（frame.jpg）的畫面區鋪滿螢幕，
   和首頁轉場最後那一張、exam.js 的 cover 一樣（貼圖座標 1024x768，畫面區 40,118,944,532） */
body.is-loading #rift {
  --s: max(calc(100vw / 944), calc(100vh / 532));
  --s: max(calc(100vw / 944), calc(100dvh / 532));
  background: #000 url(frame.jpg) no-repeat;
  background-size: calc(var(--s) * 1024) calc(var(--s) * 768);
  background-position: calc(50vw - var(--s) * 512) calc(50vh - var(--s) * 384);
  background-position: calc(50vw - var(--s) * 512) calc(50dvh - var(--s) * 384);
}
#scar { position: fixed; inset: 0; width: 100%; height: 100%; z-index: 4; pointer-events: none; display: none; }
body.in-remote #scar { display: block; }
#remote { position: fixed; inset: 0; width: 100vw; height: 100vh; height: 100svh; border: 0; z-index: 0; background: #000; }
body.exam .page { position: relative; z-index: 2; height: 100svh; min-height: 0; pointer-events: none; }
body.exam .page > * { pointer-events: auto; }
body.exam .page > main { flex: 1; display: flex; padding-bottom: 0; max-width: none; }

/* 頂列：在深空上一律用淺色字 */
body.exam .brand-name { color: var(--txt); }
body.exam .brand-sub { color: var(--txt-3); }
body.exam .pill { background: rgba(255, 255, 255, .06); border-color: rgba(255, 255, 255, .16); color: var(--txt); }
body.exam .pill:hover { background: rgba(255, 255, 255, .12); }
body.exam #themeBtn { display: none; }   /* 這一頁固定是深色，主題按鈕沒有作用；語言選單仍然插在它前面 */

.vh { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); clip-path: inset(50%); white-space: nowrap; }

body.exam .foot { color: var(--txt-3); font-size: .75rem; padding-bottom: max(10px, env(safe-area-inset-bottom)); transition: opacity .5s ease; }
body.exam .foot a { color: var(--txt-2); }

/* 掉進去的時候頂列、頁尾先藏起來；到了深空（選電腦）再回來 */
body.exam .top { transition: opacity .5s ease; }
body.is-diving .top, body.is-diving .foot { opacity: 0; pointer-events: none; }
body.is-diving.is-in-void .top, body.is-diving.is-in-void .foot { opacity: 1; pointer-events: auto; }
body.in-remote .page { display: none; }

/* ---------- 選電腦 ---------- */
.pick {
  position: fixed; inset: 0; z-index: 3; display: grid; place-content: center; justify-items: center; gap: clamp(.8rem, 2.6vh, 1.8rem);
  padding: 2rem 1rem; transition: opacity .5s ease; pointer-events: none;
}
.pick > * { pointer-events: auto; }
.pick-lede { margin: 0; font-family: var(--font-mono); font-size: .8rem; letter-spacing: .3em; color: #ffd9b0; opacity: 0; }
.pick-note { margin: 0; font-size: .8rem; color: var(--txt-3); opacity: 0; }
.pick.is-in .pick-lede { animation: pick-in .8s ease 0s both; }
.pick.is-in .pick-note { animation: pick-in .8s ease .7s both; }
.pick[hidden] { display: none; }
.pick-title { margin: 0; font-size: clamp(1.3rem, 2.2vw, 1.9rem); font-weight: 900; letter-spacing: .08em; color: var(--txt); opacity: 0; }
.pick-row { display: flex; gap: clamp(1.5rem, 6vw, 6rem); align-items: flex-end; }
.pick-os {
  appearance: none; background: none; border: 0; padding: .4rem; cursor: pointer; color: var(--txt);
  display: flex; flex-direction: column; align-items: center; gap: 1.1rem; font: inherit; opacity: 0;
  transition: transform .45s cubic-bezier(.2, .7, .2, 1), opacity .45s ease, filter .45s ease;
}
.lap { display: block; width: clamp(220px, 27vw, 430px); }
.lap-lid {
  display: block; aspect-ratio: 16 / 10.4; padding: 2.4%; border-radius: 14px 14px 5px 5px;
  background: #0a0b0f; border: 1px solid rgba(255, 255, 255, .16); overflow: hidden;
}
.lap-lid img { display: block; width: 100%; height: 100%; object-fit: cover; border-radius: 4px; filter: brightness(.8) saturate(.9); transition: filter .35s ease; }
.lap-base { display: block; height: clamp(8px, .8vw, 12px); width: 114%; margin-left: -7%; border-radius: 0 0 12px 12px; background: linear-gradient(#d8dce3, #8f949d); }
.pick-os[data-os="win"] .lap-base { background: linear-gradient(#5a5e66, #2c2f35); }
.pick-name { font-size: clamp(1.05rem, 1.6vw, 1.4rem); font-weight: 700; letter-spacing: .02em; }
.pick-os:hover, .pick-os:focus-visible { transform: translateY(-8px); }
.pick-os:hover .lap-lid img, .pick-os:focus-visible .lap-lid img { filter: brightness(1) saturate(1); }
.pick-os:hover .lap-lid, .pick-os:focus-visible .lap-lid { border-color: rgba(120, 185, 255, .7); }
.pick-os:focus-visible { outline: none; }
.pick-os:focus-visible .pick-name { text-decoration: underline; text-underline-offset: .3em; }
.pick-prog { display: block; margin-top: .3rem; font-family: var(--font-mono); font-size: .78rem; letter-spacing: .1em; color: #f5b51d; }
.pick-prog[hidden] { display: none; }
.pick-again { margin: 0; padding: .2rem .4rem; border: 0; background: none; color: var(--txt-3); font: inherit; font-size: .8rem; text-decoration: underline; text-underline-offset: 3px; cursor: pointer; pointer-events: auto; }
.pick-again:hover, .pick-again:focus-visible { color: var(--txt); }
.pick-again[hidden] { display: none; }
.pick-status { margin: 0; min-height: 1.6em; font-family: var(--font-mono); font-size: .9rem; letter-spacing: .06em; color: #9fc8ff; }

/* 兩台筆電從深空裡慢慢凝聚出來 */
.pick.is-in .pick-title { animation: pick-in .8s ease .1s both; }
.pick.is-in .pick-os { animation: pick-in 1s cubic-bezier(.2, .7, .2, 1) both; }
.pick.is-in .pick-os:nth-child(1) { animation-delay: .25s; }
.pick.is-in .pick-os:nth-child(2) { animation-delay: .45s; }
@keyframes pick-in {
  from { opacity: 0; filter: blur(12px); transform: translateY(26px) scale(.95); }
  to { opacity: 1; filter: blur(0); transform: none; }
}
.pick.is-in .pick-os { opacity: 1; }
/* 無重力：兩台筆電各自慢慢浮動 */
.pick.is-in .lap { animation: float-a 6s ease-in-out 1.2s infinite alternate; }
.pick.is-in .pick-os:nth-child(2) .lap { animation-name: float-b; animation-duration: 7s; }
@keyframes float-a { from { transform: translateY(-5px) rotate(-.8deg); } to { transform: translateY(6px) rotate(.6deg); } }
@keyframes float-b { from { transform: translateY(6px) rotate(.7deg); } to { transform: translateY(-5px) rotate(-.6deg); } }
.pick.is-chosen .pick-os { animation: none; opacity: 1; }
.pick.is-chosen .pick-os.is-off { opacity: .12; filter: blur(3px); transform: scale(.97); pointer-events: none; }
.pick.is-chosen .pick-os.is-on { transform: scale(1.05); pointer-events: none; }
.pick.is-chosen .pick-os.is-on .lap-lid { border-color: rgba(160, 210, 255, .9); }
.pick.is-chosen .pick-os.is-on .lap-lid img { filter: brightness(1.05); }
.pick.is-leaving { opacity: 0; pointer-events: none; transition: opacity .7s ease; }
.pick.is-leaving .pick-os.is-on { transform: scale(1.5); filter: blur(4px); transition: transform .8s cubic-bezier(.5, 0, .75, 0), filter .8s ease; }   /* 選的那台往鏡頭衝過來，像是要鑽進螢幕 */

@media (max-width: 640px) {
  .pick-row { flex-direction: column; align-items: center; gap: 1.6rem; }
  .lap { width: min(68vw, 300px); }
}

/* 時間膨脹讀數：左上角，越接近事件視界越紅（--red 由 exam.js 設定 0–1） */
.hud {
  --red: 0;
  position: fixed; left: max(20px, env(safe-area-inset-left)); top: max(18px, env(safe-area-inset-top)); z-index: 3; margin: 0;
  display: grid; gap: .15rem; font-family: var(--font-mono); pointer-events: none;
  color: color-mix(in srgb, #ffe6cc calc((1 - var(--red)) * 100%), #ff5a3c);
  opacity: 0; transition: opacity .35s ease;
}
.hud.is-on { opacity: 1; }
.hud-k { font-size: .7rem; letter-spacing: .28em; opacity: .75; }
.hud-v { font-size: clamp(1.6rem, 3vw, 2.4rem); font-weight: 700; letter-spacing: .02em; font-variant-numeric: tabular-nums; }
.hud-c { font-size: .85rem; letter-spacing: .08em; font-variant-numeric: tabular-nums; opacity: .85; }

.skip {
  position: fixed; right: max(16px, env(safe-area-inset-right)); bottom: max(16px, env(safe-area-inset-bottom)); z-index: 4;
  appearance: none; height: 2.3rem; padding: 0 1rem; border-radius: 999px; cursor: pointer; font: inherit; font-size: .85rem; font-weight: 700;
  color: var(--txt-2); background: rgba(255, 255, 255, .06); border: 1px solid rgba(255, 255, 255, .18);
}
.skip:hover { color: #fff; background: rgba(255, 255, 255, .12); }
.skip[hidden] { display: none; }

/* ---------- WARNING（連進遠端電腦之後，洛克人 BOSS 來襲那種，現代版） ----------
   一條半透明的暗紅帶子從中間打開，上下兩條斜紋警示帶一直流動，WARNING 亮三次（和警報聲同步），
   畫面四周跟著泛紅；約 2.9 秒後收掉。不擋操作（pointer-events: none）。 */
.warn { position: fixed; left: 0; right: 0; top: clamp(56px, 12vh, 132px); z-index: 6; pointer-events: none; visibility: hidden; }
.warn.is-on { visibility: visible; }
.warn-band {
  position: relative; min-height: clamp(96px, 15vh, 150px); padding: 22px 0 20px; box-sizing: border-box; overflow: hidden; transform: scaleY(0);
  display: flex; flex-direction: column; align-items: center; justify-content: center; gap: clamp(8px, 1.4vh, 14px);
  background: linear-gradient(90deg, rgba(30, 2, 10, 0), rgba(34, 3, 12, .82) 16%, rgba(34, 3, 12, .82) 84%, rgba(30, 2, 10, 0));
  -webkit-backdrop-filter: blur(6px) saturate(150%); backdrop-filter: blur(6px) saturate(150%);
}
.warn-band::before, .warn-band::after {
  content: ""; position: absolute; left: 0; right: 0; height: 9px; opacity: .9;
  background: repeating-linear-gradient(-45deg, #ff2d4a 0 12px, transparent 12px 24px);
  animation: warn-stripes .5s linear infinite;
}
.warn-band::before { top: 0; }
.warn-band::after { bottom: 0; animation-direction: reverse; }
@keyframes warn-stripes { to { background-position: 33.94px 0; } }
.warn-line { position: absolute; left: 0; right: 0; height: 1px; background: #ff5a70; box-shadow: 0 0 12px 1px rgba(255, 45, 74, .9); transform: scaleX(0); }
.warn-line.t { top: 15px; }
.warn-line.b { bottom: 15px; }
.warn-word {
  position: relative; font-family: var(--font-mono); font-weight: 700; line-height: 1;
  font-size: clamp(2rem, 7.4vw, 5.4rem); letter-spacing: .3em; padding-left: .3em; color: #ff3654;
  text-shadow: 0 0 22px rgba(255, 40, 70, .8), 0 0 2px rgba(255, 255, 255, .9); opacity: 0;
}
.warn-word::before, .warn-word::after { content: attr(data-text); position: absolute; inset: 0; padding-left: .3em; mix-blend-mode: screen; opacity: .55; }
.warn-word::before { color: #31e1ff; transform: translateX(-3px); }
.warn-word::after { color: #ff1f5a; transform: translateX(3px); }
.warn-sub2:empty { display: none; }
.warn-sub2 { position: relative; font-size: clamp(.8rem, 1.5vw, 1.05rem); font-weight: 700; letter-spacing: .2em; color: #ffd6dc; opacity: 0; }
.warn.is-on .warn-sub2 { animation: warn-sub 2.9s ease both; }
/* 還沒完成任務就想離開：同一條紅帶子，短一點 */
.warn.is-short .warn-band, .warn.is-short .warn-line, .warn.is-short .warn-word, .warn.is-short .warn-sub, .warn.is-short .warn-sub2 { animation-duration: 1.9s, 0.12s; }
body.warn-on.warn-short .warn-vig { animation-duration: 1.9s; }
/* 完成任務、空間穩定了：換成紫白色 */
.warn.is-safe .warn-band { background: linear-gradient(90deg, rgba(14, 8, 34, 0), rgba(18, 12, 44, .82) 16%, rgba(18, 12, 44, .82) 84%, rgba(14, 8, 34, 0)); }
.warn.is-safe .warn-band::before, .warn.is-safe .warn-band::after { background: repeating-linear-gradient(-45deg, #b9a8ff 0 12px, transparent 12px 24px); }
.warn.is-safe .warn-line { background: #d7ccff; box-shadow: 0 0 12px 1px rgba(160, 130, 255, .9); }
.warn.is-safe .warn-word { color: #efeaff; text-shadow: 0 0 22px rgba(150, 120, 255, .85), 0 0 2px #fff; }
.warn.is-safe .warn-sub2 { color: #e6e0ff; }
body.warn-on.warn-safe .warn-vig { background: radial-gradient(ellipse at center, transparent 52%, rgba(130, 100, 255, .35) 100%); }
.warn-sub { position: relative; font-family: var(--font-mono); font-size: clamp(.55rem, 1.1vw, .78rem); letter-spacing: .42em; color: rgba(255, 220, 226, .82); opacity: 0; }
.warn-vig { position: fixed; inset: 0; z-index: 5; pointer-events: none; opacity: 0; background: radial-gradient(ellipse at center, transparent 52%, rgba(255, 20, 50, .42) 100%); }
.warn.is-on .warn-band { animation: warn-open 2.9s cubic-bezier(.2, .8, .2, 1) both; }
.warn.is-on .warn-line { animation: warn-line 2.9s ease both; }
.warn.is-on .warn-word { animation: warn-blink 2.9s steps(1, end) both, warn-jit 0.12s steps(2, end) infinite; }
.warn.is-on .warn-sub { animation: warn-sub 2.9s ease both; }
body.warn-on .warn-vig { animation: warn-pulse 2.9s ease both; }
/* WARNING 本身：4.3 秒，跟著洛克人 X4 的警報聲（每秒一次）亮四次，亮紅和暗紅交替 */
.warn.is-on:not(.is-short):not(.is-safe) .warn-band { animation: warn-open4 4.3s cubic-bezier(.2, .8, .2, 1) both; }
.warn.is-on:not(.is-short):not(.is-safe) .warn-line { animation: warn-line4 4.3s ease both; }
.warn.is-on:not(.is-short):not(.is-safe) .warn-word { animation: warn-blink4 4.3s steps(1, end) both, warn-jit 0.12s steps(2, end) infinite; }
.warn.is-on:not(.is-short):not(.is-safe) .warn-sub, .warn.is-on:not(.is-short):not(.is-safe) .warn-sub2 { animation: warn-sub4 4.3s ease both; }
body.warn-on:not(.warn-short):not(.warn-safe) .warn-vig { animation: warn-pulse4 4.3s ease both; }
@keyframes warn-open4 { 0% { transform: scaleY(0); } 3% { transform: scaleY(1); } 93% { transform: scaleY(1); } 100% { transform: scaleY(0); } }
@keyframes warn-line4 { 0% { transform: scaleX(0); opacity: 1; } 4% { transform: scaleX(1); } 91% { transform: scaleX(1); opacity: 1; } 100% { transform: scaleX(0); opacity: 0; } }
@keyframes warn-blink4 {
  0% { opacity: 0; } 1%, 17% { opacity: 1; } 17.5%, 24% { opacity: .16; } 24.6%, 41% { opacity: 1; } 41.5%, 47% { opacity: .16; }
  47.7%, 64% { opacity: 1; } 64.5%, 70.5% { opacity: .16; } 71%, 88% { opacity: 1; } 89%, 100% { opacity: 0; }
}
@keyframes warn-sub4 { 0%, 5% { opacity: 0; } 9%, 88% { opacity: 1; } 94%, 100% { opacity: 0; } }
@keyframes warn-pulse4 { 0% { opacity: 0; } 3% { opacity: 1; } 18% { opacity: .2; } 26% { opacity: 1; } 41% { opacity: .2; } 49% { opacity: 1; } 64% { opacity: .2; } 72% { opacity: .9; } 92%, 100% { opacity: 0; } }
@keyframes warn-open { 0% { transform: scaleY(0); } 7% { transform: scaleY(1); } 88% { transform: scaleY(1); } 100% { transform: scaleY(0); } }
@keyframes warn-line { 0% { transform: scaleX(0); opacity: 1; } 9% { transform: scaleX(1); } 86% { transform: scaleX(1); opacity: 1; } 100% { transform: scaleX(0); opacity: 0; } }
@keyframes warn-blink { 0%, 8% { opacity: 0; } 9%, 26% { opacity: 1; } 27%, 33% { opacity: .08; } 34%, 51% { opacity: 1; } 52%, 58% { opacity: .08; } 59%, 85% { opacity: 1; } 86%, 100% { opacity: 0; } }
@keyframes warn-jit { 0% { transform: translateX(0); } 50% { transform: translateX(1.5px); } }
@keyframes warn-sub { 0%, 12% { opacity: 0; } 18%, 82% { opacity: 1; } 90%, 100% { opacity: 0; } }
@keyframes warn-pulse { 0% { opacity: 0; } 10% { opacity: 1; } 24% { opacity: .2; } 35% { opacity: 1; } 49% { opacity: .2; } 60% { opacity: .9; } 88%, 100% { opacity: 0; } }
@media (prefers-reduced-motion: reduce) {
  .warn.is-on .warn-band { animation: warn-open 2.9s linear both; }
  .warn.is-on .warn-word { animation: warn-sub 2.9s ease both; }
  .warn-band::before, .warn-band::after { animation: none; }
  body.warn-on .warn-vig { animation: none; }
}

@media (prefers-reduced-motion: reduce) {
  .pick.is-in .lap { animation: none; }
  .pick.is-in .pick-title, .pick.is-in .pick-os, .pick.is-in .pick-lede, .pick.is-in .pick-note { animation: none; opacity: 1; }
  .pick-os, .pick { transition: opacity .3s ease; }
}

/* ---------- 考試的四關（exam-levels.js、exam-quiz.js、exam-wall.js） ---------- */
/* 遠端畫面四周的暗角：空間還不穩定；每過一關淡一點（exam.js 的 setStage）。老師的參考圖是中性的暗，不偏紫紅 */
#exam-vign {
  position: fixed; inset: 0; z-index: 3; pointer-events: none; opacity: 0; transition: opacity 1.6s ease;
  background: radial-gradient(ellipse at center, transparent 60%, rgba(8, 9, 13, .38) 88%, rgba(4, 4, 7, .55) 100%);
}
body:not(.in-remote) #exam-vign { display: none; }

/* 第 4 關的問答窗：整個畫面蓋住，只能選選項、按確認 */
.quiz {
  position: fixed; inset: 0; z-index: 8; display: grid; place-items: center; padding: 16px;
  background: rgba(3, 3, 10, .72); opacity: 0; transition: opacity .45s ease;
}
.quiz.is-in { opacity: 1; }
.quiz.is-out { opacity: 0; }
.quiz-panel {
  width: min(760px, 100%); max-height: calc(100svh - 32px); overflow: auto;
  background: rgba(10, 9, 20, .96); border: 1px solid rgba(255, 255, 255, .12); border-radius: 6px;
  padding: clamp(18px, 3.2vw, 34px) clamp(18px, 3.6vw, 40px) clamp(16px, 2.6vw, 26px);
  color: var(--txt); transform: translateY(8px); transition: transform .45s ease, border-color .6s ease;
}
.quiz.is-in .quiz-panel { transform: none; }
.quiz-head { display: flex; justify-content: space-between; align-items: baseline; gap: 1rem; font-family: var(--font-mono); font-size: .78rem; letter-spacing: .14em; color: var(--txt-3); }
.quiz-count { color: var(--txt-2); }
.quiz-bar { height: 1px; background: rgba(255, 255, 255, .12); margin: .7rem 0 1.4rem; }
.quiz-bar i { display: block; height: 1px; width: 0; background: #b9b2ff; transition: width .5s ease; }
.quiz-story { margin: 0 0 .6rem; font-size: clamp(1.05rem, 1.7vw, 1.25rem); line-height: 1.7; }
.quiz-rule { margin: 1.1rem 0 0; color: var(--txt-2); font-size: .95rem; line-height: 1.7; }
.quiz-q { margin: 0 0 1.1rem; font-size: clamp(1.05rem, 1.8vw, 1.28rem); font-weight: 700; line-height: 1.6; }
.quiz-opts { display: grid; border-top: 1px solid rgba(255, 255, 255, .1); }
.quiz-opt {
  display: grid; grid-template-columns: 2.1rem 1fr auto; align-items: baseline; gap: .4rem; text-align: left;
  padding: .78rem .2rem; border: 0; border-bottom: 1px solid rgba(255, 255, 255, .1); background: none; color: var(--txt);
  font: inherit; font-size: 1rem; line-height: 1.6; cursor: pointer;
}
.quiz-opt:hover:not(:disabled) .quiz-txt { color: #fff; text-decoration: underline; text-decoration-color: rgba(185, 178, 255, .6); text-underline-offset: 4px; }
.quiz-opt:focus-visible { outline: 1px solid #b9b2ff; outline-offset: 2px; }
.quiz-let { font-family: var(--font-mono); font-size: .85rem; color: var(--txt-3); }
.quiz-mark { font-family: var(--font-mono); font-size: .8rem; letter-spacing: .1em; }
.quiz-opt.is-pick .quiz-let, .quiz-opt.is-pick .quiz-txt { color: #d9d4ff; }
.quiz-opt.is-pick .quiz-txt { text-decoration: underline; text-decoration-color: #b9b2ff; text-underline-offset: 4px; }
.quiz-opt.is-no { cursor: default; }
.quiz-opt.is-no .quiz-txt { color: var(--txt-3); text-decoration: line-through; text-decoration-color: rgba(255, 120, 140, .7); }
.quiz-opt.is-no .quiz-mark { color: #ff8fa0; }
.quiz-opt.is-yes .quiz-txt, .quiz-opt.is-yes .quiz-let { color: #c9f5d8; }
.quiz-opt.is-yes .quiz-mark { color: #8fe3ad; }
.quiz-opt.is-dim { opacity: .45; cursor: default; }
.quiz-why { display: none; margin-top: 1.1rem; padding-top: .2rem; }
.quiz-why.is-on { display: block; animation: pick-in .5s ease both; }
.quiz-why-k { font-family: var(--font-mono); font-size: .75rem; letter-spacing: .2em; color: var(--txt-3); }
.quiz-why-t { margin: .35rem 0 .3rem; line-height: 1.8; color: var(--txt-2); }
.quiz-why-from { font-size: .8rem; color: var(--txt-3); }
.quiz-foot { display: flex; justify-content: space-between; align-items: center; gap: 1rem; margin-top: 1.4rem; min-height: 2.4rem; }
.quiz-note { color: #ff9fae; font-size: .9rem; }
.quiz-btn {
  margin-left: auto; padding: .55rem 1.3rem; border: 1px solid rgba(185, 178, 255, .7); border-radius: 4px; background: none;
  color: #e6e2ff; font: inherit; font-size: .95rem; letter-spacing: .06em; cursor: pointer;
}
.quiz-btn:hover:not(:disabled) { background: rgba(185, 178, 255, .12); }
.quiz-btn:focus-visible { outline: 1px solid #fff; outline-offset: 2px; }
.quiz-btn:disabled { opacity: .35; cursor: default; }
@media (prefers-reduced-motion: reduce) { .quiz, .quiz-panel, .quiz-bar i, #exam-vign { transition: none; } .quiz-why.is-on { animation: none; } }

/* 考試的帶路（exam-guide.js）：小安的通訊、任務簡報、目標列、時空穩定度。
   深色面板、細線、小安的橘色是唯一的強調色，穩定度用紫色；不用發光卡片、不做雜訊或撕裂的效果。 */
#guide {
  --g-panel: rgba(8, 9, 16, .88); --g-line: rgba(241, 239, 233, .16); --g-amber: #f5b51d; --g-violet: #84a3d6; --g-label: #8b9abc;
  --g-bar: clamp(44px, 9.5vh, 92px);
  position: fixed; inset: 0; z-index: 5; pointer-events: none; color: var(--txt); font-family: var(--font-body);
}
body:not(.in-remote) #guide { display: none; }
#guide .g-k { font-family: var(--font-mono); font-size: 12px; letter-spacing: .2em; color: var(--txt-3); }
#guide .g-amber { color: var(--g-amber); }
.g-dim { position: absolute; inset: 0; background: rgba(4, 4, 10, .52); opacity: 0; transition: opacity .5s ease; }
.g-bar { position: absolute; left: 0; right: 0; height: var(--g-bar); background: #000; transition: transform .5s cubic-bezier(.2, .7, .2, 1); }
.g-top { top: 0; transform: translateY(-100%); }
.g-bot { bottom: 0; transform: translateY(100%); }
.g-catch { position: absolute; inset: 0; }
#guide.is-cut .g-catch { pointer-events: auto; cursor: default; }
#guide.is-bars .g-dim { opacity: 1; }
#guide.is-bars .g-bar { transform: none; }

/* 任務簡報：任務編號、標題、目標、時空穩定度 */
.g-title {
  position: absolute; left: 50%; top: 40%; width: min(780px, 90vw); text-align: center;
  transform: translate(-50%, calc(-50% + 10px)); opacity: 0; transition: opacity .5s ease, transform .6s cubic-bezier(.2, .7, .2, 1);
}
#guide.is-title .g-title { opacity: 1; transform: translate(-50%, -50%); }
.g-title h2 { margin: 12px 0 0; font-size: clamp(32px, 4.4vw, 56px); font-weight: 700; letter-spacing: .06em; line-height: 1.2; }
.g-rule { width: min(340px, 60%); height: 1px; margin: 20px auto 18px; background: linear-gradient(90deg, transparent, rgba(240, 181, 69, .85), transparent); }
.g-goal {
  display: inline-flex; gap: 16px; align-items: baseline; max-width: 100%; padding: 11px 18px; text-align: left;
  border-top: 1px solid var(--g-line); border-bottom: 1px solid var(--g-line); opacity: 0; transition: opacity .5s ease;
}
.g-goal .g-k { flex: none; white-space: nowrap; }
.g-goal span:last-child { font-size: clamp(15px, 1.5vw, 19px); line-height: 1.6; }
#guide.is-goal .g-goal { opacity: 1; }
.g-title .g-stab { justify-content: center; margin-top: 22px; }
.g-stab { display: flex; align-items: center; gap: 12px; }
/* 時空穩定度：一格一格的 LED 刻度（每格裡再分成 3 px 的小刻）。修好的格子是綠色的：從左往右填滿，
   之後每隔幾秒有一道光從第一格掃到最後一格（老師 2026-10-18：成功後改綠色、要有科技感）。 */
#guide { --g-ok: #4be3a3; --g-ok-hi: #b8ffe0; }
.g-segs { display: inline-flex; gap: 5px; }
.g-segs i {
  position: relative; overflow: hidden; width: 34px; height: 5px; border-radius: 1px;
  background: repeating-linear-gradient(90deg, rgba(170, 176, 188, .3) 0 3px, transparent 3px 4px);
  transition: box-shadow .6s ease;
}
.g-segs i::before {
  content: ""; position: absolute; inset: 0;
  background: repeating-linear-gradient(90deg, var(--g-ok) 0 3px, rgba(75, 227, 163, .25) 3px 4px);
  transform: scaleX(0); transform-origin: left center; transition: transform .75s cubic-bezier(.2, .7, .2, 1);
}
.g-segs i.on::before { transform: scaleX(1); }
.g-segs i.on { box-shadow: 0 0 6px rgba(75, 227, 163, .45), 0 0 1px rgba(184, 255, 224, .6); }
.g-segs i::after {
  content: ""; position: absolute; top: 0; bottom: 0; left: -60%; width: 60%; opacity: 0;
  background: linear-gradient(90deg, transparent, rgba(220, 255, 240, .95), transparent);
}
.g-segs i.on::after { animation: g-sweep 3.2s cubic-bezier(.4, 0, .2, 1) infinite; }
.g-segs i:nth-child(2)::after { animation-delay: .14s; }
.g-segs i:nth-child(3)::after { animation-delay: .28s; }
.g-segs i:nth-child(4)::after { animation-delay: .42s; }
.g-segs i.is-new.on::after { animation: g-sweep .9s .55s cubic-bezier(.4, 0, .2, 1) 1, g-sweep 3.2s 1.6s cubic-bezier(.4, 0, .2, 1) infinite; }
@keyframes g-sweep { 0% { left: -60%; opacity: 0; } 10% { opacity: 1; } 32% { left: 100%; opacity: 1; } 33%, 100% { left: 100%; opacity: 0; } }
#guide .g-pct { color: var(--g-violet); letter-spacing: .1em; min-width: 3.2em; transition: color .6s ease; }
#guide .g-pct.is-on { color: var(--g-ok); }

/* 小安的通訊：先收到訊號，再接通（面板從中間打開），說完斷線收起來；不會一直留在畫面上 */
.g-comm { position: absolute; left: 50%; bottom: calc(var(--g-bar) + 20px); width: min(690px, 92vw); transform: translateX(-50%); visibility: hidden; }
.g-comm.is-call { visibility: visible; }
.g-comm.is-toast { left: var(--col-x, 12px); bottom: var(--dock, 100px); width: var(--col-w, 330px); transform: none; }
.g-call { display: flex; align-items: center; gap: 8px; margin: 0 0 8px 2px; font-family: var(--font-mono); font-size: 12px; letter-spacing: .2em; color: var(--g-amber); text-shadow: 0 1px 3px rgba(0, 0, 0, .7); }
.g-dot { width: 6px; height: 6px; border-radius: 50%; background: var(--g-amber); animation: g-blink 1s steps(2, start) infinite; }
.g-comm.is-open .g-dot { animation: none; }
.g-comm.is-end .g-call { color: var(--txt-3); }
.g-comm.is-end .g-dot { background: var(--txt-3); }
@keyframes g-blink { to { visibility: hidden; } }
.g-panel {
  display: grid; grid-template-columns: 104px 1fr; gap: 20px; padding: 18px 22px 16px 18px;
  background: var(--g-panel); border-top: 1px solid rgba(240, 181, 69, .5);
  clip-path: inset(50% 0 50% 0); transition: clip-path .32s cubic-bezier(.2, .7, .2, 1);
}
.g-comm.is-open .g-panel { clip-path: inset(0 0 0 0); }
.g-face { position: relative; width: 104px; height: 104px; overflow: hidden; border: 1px solid var(--g-line); background: radial-gradient(circle at 50% 62%, rgba(240, 181, 69, .14), rgba(0, 0, 0, 0) 70%); }
.g-face img { position: absolute; left: 50%; top: 52%; width: 92%; transform: translate(-50%, -50%); animation: g-signal 3.2s ease-in-out infinite; }
/* 遠端傳來的影像：偏一點紫、亮度慢慢起伏（不做掃描線、不抖） */
.g-face::after { content: ""; position: absolute; inset: 0; background: linear-gradient(180deg, rgba(120, 100, 255, .12), rgba(20, 10, 40, .22)); }
@keyframes g-signal { 0%, 100% { opacity: .95; } 45% { opacity: .82; } 55% { opacity: 1; } }
.g-who { display: flex; justify-content: space-between; gap: 12px; margin-bottom: 8px; }
.g-lines { min-height: 3.4em; }
.g-lines p { margin: 0 0 4px; font-size: 18px; line-height: 1.7; }
.g-lines p.old { color: var(--txt-3); font-size: 15px; }
.g-foot { display: flex; justify-content: space-between; margin-top: 6px; }
#guide .g-keys { letter-spacing: .12em; }
.g-comm.is-toast .g-panel { grid-template-columns: 52px 1fr; gap: 12px; padding: 12px 14px; }
.g-comm.is-toast .g-face { width: 52px; height: 52px; }
.g-comm.is-toast .g-lines { min-height: 0; }
.g-comm.is-toast .g-lines p { font-size: 14.5px; line-height: 1.6; }
.g-comm.is-toast .g-foot, .g-comm.is-toast .g-who .g-k:first-child { display: none; }
.g-comm.is-toast .g-who::before { content: "小安"; font-family: var(--font-mono); font-size: 12px; letter-spacing: .2em; color: var(--g-amber); }

/* 目標列：放在原本任務卡的那一欄 */
.g-hud {
  position: absolute; left: var(--col-x, 12px); top: var(--col-y, 40px); width: var(--col-w, 330px); padding: 18px 20px 16px 20px;
  background: rgba(17, 20, 26, .96); border: 1px solid rgba(255, 255, 255, .06); border-left: 3px solid var(--g-amber); border-radius: 10px;
  box-shadow: 0 10px 28px rgba(0, 0, 0, .35);
  opacity: 0; transform: translateY(-6px); transition: opacity .45s ease, transform .45s ease;
}
#guide .g-hud .g-hrow .g-amber { font-size: 13px; font-weight: 700; letter-spacing: .14em; }
#guide.is-hud .g-hud { opacity: 1; transform: none; }
/* 第 2 關起，目標列的字可以用滑鼠選取、複製（老師 2026-10-18）；第 1 關滑鼠鎖著，不給選 */
#guide.is-hud.is-sel .g-hud { pointer-events: auto; cursor: text; -webkit-user-select: text; user-select: text; }
#guide.is-hud.is-sel .g-hud .g-reset { cursor: pointer; -webkit-user-select: none; user-select: none; }
#guide .g-hud ::selection { background: rgba(245, 181, 29, .38); color: #fff; }
.g-hrow { display: flex; justify-content: space-between; align-items: baseline; }
/* 重來這一關：字小，所以點擊範圍往外多留一圈；按一下變成「再按一次確定重來」（紅字），4 秒內再按才重來 */
.g-reset { pointer-events: auto; border: 0; margin: -8px -10px; padding: 8px 10px; background: none; cursor: pointer; text-decoration: underline; text-decoration-color: rgba(255, 255, 255, .22); text-underline-offset: 4px; }
#guide.is-hud .g-reset:hover { color: var(--txt); text-decoration-color: currentColor; }
#guide .g-reset.is-armed, #guide.is-hud .g-reset.is-armed:hover { color: #ff8f7e; letter-spacing: .12em; text-decoration-color: currentColor; }
.g-reset:focus-visible { outline: 1px solid var(--g-amber); outline-offset: -2px; border-radius: 4px; }
.g-reset[hidden] { display: none; }
.g-htitle { margin-top: 12px; font-size: 18px; font-weight: 600; letter-spacing: .05em; }
/* 第 1 關：目前僅能使用鍵盤打字（一亮一暗地閃，不是硬切的閃爍） */
.g-note { margin-top: 8px; font-size: 14px; font-weight: 700; letter-spacing: .08em; color: #ff8f7e; animation: g-note 1.3s ease-in-out infinite; }
.g-note[hidden] { display: none; }
@keyframes g-note { 0%, 100% { opacity: 1; } 50% { opacity: .22; } }
#guide .g-hgoal .g-k { white-space: nowrap; color: var(--g-label); font-family: var(--font-body); font-size: 14px; font-weight: 700; letter-spacing: .08em; }
.g-hgoal { display: grid; grid-template-columns: auto 1fr; gap: 12px; align-items: baseline; margin: 14px 0 16px; font-size: 15px; font-weight: 500; line-height: 2; }
.g-hud .g-stab { padding-top: 14px; border-top: 1px solid rgba(255, 255, 255, .1); }
#guide .g-hud .g-stab > .g-k:first-child { white-space: nowrap; color: var(--g-violet); font-family: var(--font-body); font-size: 14px; font-weight: 700; letter-spacing: .08em; }
.g-hud .g-segs { flex: 1 1 auto; min-width: 0; gap: 6px; }
.g-hud .g-segs i { flex: 0 1 28px; min-width: 12px; height: 4px; }
.g-hud .g-pct { margin-left: auto; font-weight: 700; }
/* 目標裡的檔名、資料夾名：小標籤 */
.g-nb { white-space: nowrap; }
.g-code { display: inline-block; margin: 0 2px; padding: 0 8px; border-radius: 7px; background: rgba(255, 255, 255, .075); font-family: var(--font-mono); font-size: .92em; line-height: 1.75; color: #e5e7eb; white-space: nowrap; }

/* 過關：修復完成，穩定度加一格 */
.g-stamp { position: absolute; left: 50%; top: 44%; transform: translate(-50%, -50%); text-align: center; opacity: 0; transition: opacity .4s ease; }
.g-stamp::before { content: ""; position: absolute; left: 50%; top: 50%; width: 180%; height: 260%; transform: translate(-50%, -50%); z-index: -1; background: radial-gradient(closest-side, rgba(4, 4, 12, .62), rgba(4, 4, 12, 0)); }
#guide.is-stamp .g-stamp { opacity: 1; }
.g-big { margin-top: 14px; font-size: clamp(34px, 4.6vw, 60px); font-weight: 700; letter-spacing: .32em; text-indent: .32em; text-shadow: 0 2px 18px rgba(0, 0, 0, .6); }
.g-stamp .g-stab { justify-content: center; margin-top: 22px; }
.g-stamp .g-segs i { width: 56px; height: 6px; }

/* 要去的地方亮兩圈 */
.g-ping { position: absolute; width: 0; height: 0; }
.g-ping i { position: absolute; left: -40px; top: -40px; width: 80px; height: 80px; border: 1.5px solid var(--g-amber); border-radius: 50%; opacity: 0; }
.g-ping.is-on i { animation: g-ping 1.25s cubic-bezier(.2, .7, .2, 1) 2; }
.g-ping.is-on i + i { animation-delay: .32s; }
@keyframes g-ping { 0% { transform: scale(.45); opacity: 0; } 25% { opacity: .95; } 100% { transform: scale(1.35); opacity: 0; } }

@media (prefers-reduced-motion: reduce) {
  .g-dim, .g-bar, .g-title, .g-goal, .g-panel, .g-hud, .g-stamp, .g-segs i, .g-segs i::before, #guide .g-pct { transition: none; }
  .g-segs i.on::after, .g-segs i.is-new.on::after { animation: none; }
  .g-face img, .g-dot, .g-ping.is-on i, .g-note { animation: none; }
}

/* 第 4 關的時空轉移（exam-warp.js）：畫在問答窗後面；問答窗的底色調淡，看得到後面的轉移 */
#warp { position: fixed; inset: 0; width: 100%; height: 100%; z-index: 4; pointer-events: none; display: none; opacity: 0; }
body.in-warp .quiz { background: rgba(3, 3, 10, .2); }
/* 問答時小安照樣能說話：帶路那層移到問答窗上面，通訊放在左上（目標列先藏起來，免得蓋到題目） */
body.in-quiz #guide { z-index: 9; }
body.in-quiz #guide .g-hud { visibility: hidden; }
body.in-quiz #guide .g-comm.is-toast { top: var(--col-y, 40px); bottom: auto; }
/* 答錯：問答窗左右晃一下（很小、很短）；答對：邊框亮一下薄荷綠 */
.quiz-panel.is-shake { animation: quiz-shake .42s cubic-bezier(.36, .07, .19, .97) both; }
@keyframes quiz-shake {
  10%, 90% { transform: translateX(-2px); } 20%, 80% { transform: translateX(4px); }
  30%, 50%, 70% { transform: translateX(-7px); } 40%, 60% { transform: translateX(7px); }
}
.quiz-panel.is-right { border-color: rgba(126, 240, 192, .8); transition: border-color .08s ease; }
/* 老師測試用的隱藏按鈕（exam-quiz.js）：最右下角，看不見、游標不變 */
.quiz-ghost { position: absolute; right: 0; bottom: 0; width: 44px; height: 44px; z-index: 1; }

/* 四關都過了、按「中斷連線」：時空回歸（exam.js 的 exitHome）。遠端桌面縮進概念圖的黑洞，概念圖畫在它後面 */
body.is-exiting #remote { z-index: 3; }
#exitCv { position: fixed; inset: 0; width: 100%; height: 100%; z-index: 2; pointer-events: none; }
#exitGlow {
  position: fixed; inset: 0; z-index: 4; pointer-events: none; opacity: 0; transform-origin: 50% 50%;
  background: radial-gradient(ellipse at center, rgba(255, 255, 255, .96), rgba(214, 206, 255, .88));
}
body.is-exiting :is(#guide, #scar, #exam-vign, .warn, .warn-vig, #warp, .sound-btn) { opacity: 0 !important; transition: opacity .3s ease; pointer-events: none; }
/* 通關、時空隧道直接接回首頁（exam.js 的 tunnelHome）：小安的通訊留著（蓋在隧道和概念圖上面），其他的收起來 */
body.is-tunneling #guide { z-index: 9; }
body.is-tunneling :is(#guide .g-hud, #scar, #exam-vign, .warn, .warn-vig, .sound-btn) { opacity: 0 !important; transition: opacity .3s ease; pointer-events: none; }
/* 時空回歸的準星框（四個角跟著遠端桌面縮小、鎖定）和字幕（RETURNING TO REALITY → WELCOME BACK）；只用細線和字，不做發光卡片 */
#exitHud { position: fixed; left: 0; top: 0; z-index: 5; pointer-events: none; opacity: 0; --c: 24px; }
#exitHud i { position: absolute; width: var(--c); height: var(--c); border: 0 solid rgba(226, 220, 255, .95); }
#exitHud .tl { left: 0; top: 0; border-left-width: 2px; border-top-width: 2px; }
#exitHud .tr { right: 0; top: 0; border-right-width: 2px; border-top-width: 2px; }
#exitHud .bl { left: 0; bottom: 0; border-left-width: 2px; border-bottom-width: 2px; }
#exitHud .br { right: 0; bottom: 0; border-right-width: 2px; border-bottom-width: 2px; }
#exitCap {
  position: fixed; left: 50%; bottom: 12vh; z-index: 5; transform: translateX(-50%); pointer-events: none; opacity: 0; text-align: center; white-space: nowrap;
  font-family: var(--font-mono); font-size: 13px; font-weight: 700; letter-spacing: .52em; color: #eeeaff; text-shadow: 0 1px 8px rgba(4, 3, 10, .8);
}
#exitCap .bar { display: block; width: 240px; height: 1px; margin: 12px auto 0; background: rgba(255, 255, 255, .2); }
#exitCap .bar i { display: block; width: 0; height: 100%; background: #d6ceff; }
/* WELCOME BACK 放大（學生 2026-10-23：成功返回的字太小）：桌機約 56px、手機 26px 起；text-indent 補上最後一個字後面的字距，才會置中 */
#exitCap.is-back { bottom: 13vh; font-size: clamp(26px, 3.9vw, 60px); font-weight: 600; letter-spacing: .26em; text-indent: .26em; line-height: 1.1; text-shadow: 0 2px 18px rgba(4, 3, 10, .85), 0 1px 3px rgba(4, 3, 10, .6); }
#exitCap.is-back .bar { display: none; }
#exitCap .s { display: none; margin-top: 10px; font-size: 11px; font-weight: 400; letter-spacing: .46em; color: #cfc8f2; }
#exitCap.is-back .s { margin-top: .9em; font-size: clamp(11px, .3em, 17px); font-weight: 500; letter-spacing: .46em; text-indent: .46em; color: #e6e1ff; }
#exitCap.is-back .s:not(:empty) { display: block; }