/* 弧形作品架（演示）：Switch 式的单一焦点 + 弧形纵深 */
.arc-page { background: #060607; overflow: hidden; }
.arc-header { background: transparent !important; border-bottom-color: transparent !important; }
.arc {
  --accent: #8fb4ff;
  /* 作品区贴着底部排：卡片底边到屏幕底边固定留 --stack（放标题、简介、按钮和进度条），
     卡片宽度再受 --top-min 限制（顶部至少留这么高给背景和状态栏）。上半屏留给背景场景。 */
  --stack: 344px;
  --info-gap: 30px;
  --top-min: 150px;
  --cwv: 44vw;
  --cwmax: 840px;
  --cw: min(var(--cwv), calc((100svh - var(--stack) - var(--top-min)) / .5625), var(--cwmax));
  --cy: calc(100svh - var(--stack) - var(--cw) * .28125);
  position: relative; height: 100vh; height: 100svh; min-height: 560px; overflow: hidden;
  user-select: none; -webkit-user-select: none; touch-action: pan-y;
}

/* ---------- 固定画布（is-staged，由 JS 判断：横屏且不太小时启用） ----------
   背景和作品 UI 都画在 1920×1080 的设计稿上，整块按 --s 等比缩放、底边贴屏幕底边、水平居中。
   --s = max(屏宽/1920, 屏高/1080)，所以画布总是铺满屏幕（多出来的部分从上方和两侧裁掉）。
   窗口拉伸、浏览器缩放都只会让整张画面一起变大变小，作品 UI 和背景的相对位置不变。
   尺寸取自用户确认的那张截图：卡片 420 宽，落在走廊地面的中下方。 */
.arc-plane { position: absolute; inset: 0; }
.arc.is-staged .arc-plane { inset: auto; left: 50%; bottom: 0; width: 1920px; height: 1080px;
  transform-origin: 50% 100%; transform: translateX(-50%) scale(var(--s, 1)); }
.arc.is-staged { --cw: 420px; --cy: 618px; --info-gap: 30px; }
.arc.is-staged .arc-info { width: 760px; }
.arc.is-staged .arc-title { font-size: 36px; }
.arc.is-staged .arc-bar { width: 440px; }

/* 背景光与地面光圈：用 color 过渡，渐变里引用 currentColor */
.arc-glow { position: absolute; inset: -10%; pointer-events: none; color: var(--accent); opacity: .22;
  background: radial-gradient(ellipse 48% 40% at 50% 39%, currentColor, transparent 72%); transition: color .6s ease; }
.arc-floor { position: absolute; left: 50%; top: calc(var(--cy) + var(--cw) * .2812 + 26px); width: calc(var(--cw) * 1.05); height: 90px;
  transform: translateX(-50%); pointer-events: none; color: var(--accent); opacity: .45;
  background: radial-gradient(ellipse 50% 50% at 50% 50%, currentColor, transparent 70%); filter: blur(18px); transition: color .6s ease; }

/* 3D 舞台 */
.arc-stage { position: absolute; inset: 0; perspective: 1700px; perspective-origin: 50% var(--cy); cursor: grab; }
.arc-stage.is-dragging { cursor: grabbing; }
.arc-world { position: absolute; left: 50%; top: var(--cy); width: 0; height: 0; transform-style: preserve-3d; }
.arc-card { position: absolute; left: 0; top: 0; display: block; width: var(--cw); aspect-ratio: 16 / 9;
  margin-left: calc(var(--cw) / -2); margin-top: calc(var(--cw) * -.28125);
  transform-style: preserve-3d; will-change: transform; border-radius: 18px; -webkit-tap-highlight-color: transparent; }
.arc-frame { position: absolute; inset: 0; border-radius: 18px; overflow: hidden; background: #111;
  box-shadow: 0 34px 90px #000c; -webkit-box-reflect: below 14px linear-gradient(transparent 72%, #ffffff26); }
.arc-frame img { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; pointer-events: none; }
.arc-card { container-type: inline-size; }
.arc-about { position: absolute; inset: 0; background: radial-gradient(ellipse 70% 90% at 75% 40%, #2c2a24, #0c0c0b 72%); }
.arc-frame .arc-about-photo { left: auto; right: 0; width: 56%; object-position: 52% 64%; filter: saturate(.8) brightness(.9) contrast(1.05);
  -webkit-mask-image: linear-gradient(90deg, transparent, #000 38%); mask-image: linear-gradient(90deg, transparent, #000 38%); }
.arc-about-text { position: absolute; left: 7%; top: 0; bottom: 0; display: flex; flex-direction: column; justify-content: center; gap: 2.4cqw; }
.arc-about-mono { font: 800 9cqw/1 var(--f-display, sans-serif); letter-spacing: -.03em; color: #f2efe8; }
.arc-about-mono b { color: #d7bda0; font-weight: 800; }
.arc-about-name { font-size: 4.4cqw; font-weight: 800; color: #f2efe8; line-height: 1.1; }
.arc-about-name small { display: block; margin-top: .8cqw; font: 600 1.7cqw/1 var(--f-mono, monospace); letter-spacing: .2em; color: #ffffffa0; }
.arc-about-role { font: 1.5cqw/1 var(--f-mono, monospace); letter-spacing: .18em; color: #d7bda0; }
.arc-shade { position: absolute; inset: 0; background: #050506; pointer-events: none; }
.arc-tag { position: absolute; left: 16px; top: 14px; font: 12px/1 var(--f-mono, monospace); letter-spacing: .1em; color: #fff; text-shadow: 0 1px 8px #000;
  opacity: .9; }
/* 焦点光边：Switch 式的呼吸描边 */
.arc-ring { position: absolute; inset: -8px; border-radius: 24px; border: 2px solid var(--accent); opacity: 0; pointer-events: none;
  box-shadow: 0 0 28px -4px var(--accent); transition: opacity .18s ease, border-color .4s ease; }
.arc-card.is-focus .arc-ring { opacity: 1; animation: arc-breathe 1.9s ease-in-out infinite; }
@keyframes arc-breathe { 50% { box-shadow: 0 0 48px 2px var(--accent); border-color: #fff; } }

.arc-top { position: absolute; top: calc(var(--header-h, 72px) + 14px); left: var(--gutter); right: var(--gutter);
  display: flex; justify-content: space-between; pointer-events: none; }
.arc-kicker { font: 11px/1 var(--f-mono, monospace); letter-spacing: .16em; color: #ffffff9e; }
.arc-count { color: var(--accent); transition: color .4s; }

/* 左右箭头 */
.arc-nav { position: absolute; top: var(--cy); width: 46px; height: 46px; margin-top: -23px; border-radius: 50%;
  border: 1px solid #ffffff38; background: #0008; cursor: pointer; display: grid; place-items: center; transition: border-color .2s, background .2s, opacity .2s; }
.arc-nav i { width: 10px; height: 10px; border-left: 2px solid #fff; border-bottom: 2px solid #fff; transform: rotate(45deg); margin-left: 4px; }
.arc-next i { transform: rotate(-135deg); margin-left: -4px; }
.arc-prev { left: calc(50% - var(--cw) / 2 - 76px); }
.arc-next { right: calc(50% - var(--cw) / 2 - 76px); }
.arc-nav:hover { border-color: var(--accent); background: #000b; }
.arc-nav[disabled] { opacity: .2; cursor: default; }

/* 下方信息 */
.arc-info { position: absolute; left: 50%; top: calc(var(--cy) + var(--cw) * .28125 + var(--info-gap)); width: min(760px, 88vw);
  transform: translateX(-50%); text-align: center; pointer-events: none; }
.arc-info > * { transition: opacity .16s ease, transform .22s ease; }
.arc-info.is-swapping > * { opacity: 0; transform: translateY(6px); }
.arc-line { display: flex; justify-content: center; align-items: baseline; gap: 14px; }
.arc-num { font: 700 14px/1 var(--f-mono, monospace); color: var(--accent); letter-spacing: .08em; transition: color .4s; }
.arc-meta { font: 11px/1 var(--f-mono, monospace); letter-spacing: .14em; color: #ffffffa8; text-transform: uppercase; }
.arc-title { margin: 12px 0 8px; font-size: clamp(30px, 3.6vw, 54px); font-weight: 800; letter-spacing: -.02em; line-height: 1.08; }
.arc-desc { margin: 0 auto; max-width: 44em; font-size: 14px; line-height: 1.75; color: #b9bdb6; }
.arc-enter { pointer-events: auto; display: inline-flex; align-items: center; gap: 12px; margin-top: 18px; padding: 11px 20px;
  border: 1px solid var(--accent); border-radius: 999px; color: #fff; font-size: 13px; letter-spacing: .04em;
  background: color-mix(in srgb, var(--accent) 16%, transparent); transition: background .2s, border-color .4s; }
.arc-enter:hover { background: var(--accent); color: #050506; }

/* 底部进度条 */
.arc-bar { position: absolute; left: 50%; bottom: 84px; width: min(440px, 76vw); transform: translateX(-50%); text-align: center; }
.arc-track { position: relative; height: 2px; border-radius: 2px; background: #ffffff2a; cursor: pointer; }
.arc-track::before { content: ""; position: absolute; inset: 0; border-radius: 2px; background: var(--arc-gradient, #fff); opacity: .75; }
.arc-knob { position: absolute; top: 50%; left: 0; width: 13px; height: 13px; margin: -6.5px 0 0 -6.5px; border-radius: 50%;
  background: var(--accent); box-shadow: 0 0 14px var(--accent); transition: background .4s; }
.arc-hint { display: block; margin-top: 12px; font: 10px/1.4 var(--f-mono, monospace); letter-spacing: .12em; color: #ffffff70; text-transform: uppercase; }

/* ---------- 背景层 ---------- */
/* 透视地面网格：canvas 画，消失点和 3D 舞台的视点一致，切换作品时横向滑动 */
.arc-grid { position: absolute; inset: 0; width: 100%; height: 100%; pointer-events: none; }
/* 超大描边标题：放进 3D 舞台，夹在侧边卡片和正中卡片之间（侧卡 z≈-0.36cw，正中 z=0），比卡片移动得慢 */
.arc-bigtitle { position: absolute; left: -50vw; width: 100vw; top: 0; text-align: center; pointer-events: none;
  transform: translate3d(0, -50%, calc(var(--cw) * -.1)); }
.arc-bigtitle span { display: inline-block; white-space: nowrap; font-family: var(--f-display, sans-serif); font-stretch: 75%; font-weight: 800;
  font-size: clamp(90px, 15vw, 300px); line-height: .9; letter-spacing: -.01em; text-transform: uppercase;
  color: transparent; -webkit-text-stroke: 1.5px var(--accent); opacity: .26; transition: opacity .18s ease; will-change: transform; }
.arc-bigtitle.is-swapping span { opacity: 0; }
/* 顶灯与光束 */
.arc-spot { position: absolute; left: 50%; top: 0; width: calc(var(--cw) * 1.5); height: calc(var(--cy) + var(--cw) * .2812);
  transform: translateX(-50%); pointer-events: none; color: var(--accent); opacity: .14; filter: blur(26px);
  background: linear-gradient(180deg, currentColor, transparent 95%); clip-path: polygon(43% 0, 57% 0, 100% 100%, 0 100%); transition: color .6s ease; }
.arc-lamp { position: absolute; left: 50%; top: calc(var(--header-h, 72px) + 4px); width: 220px; height: 16px; transform: translateX(-50%); pointer-events: none; }
.arc-lamp i { position: absolute; inset: 0; border-radius: 50%; border: 1px solid #ffffff4d;
  background: radial-gradient(ellipse 60% 80% at 50% 70%, var(--accent), transparent 72%); box-shadow: 0 8px 34px -6px var(--accent); transition: background .6s, box-shadow .6s; }
/* 四角取景框 */
.arc-corners i { position: absolute; width: 16px; height: 16px; border: 0 solid #ffffff4a; pointer-events: none; }
.arc-corners i:nth-child(1) { left: calc(var(--gutter) - 10px); top: calc(var(--header-h, 72px) + 2px); border-width: 1px 0 0 1px; }
.arc-corners i:nth-child(2) { right: calc(var(--gutter) - 10px); top: calc(var(--header-h, 72px) + 2px); border-width: 1px 1px 0 0; }
.arc-corners i:nth-child(3) { right: calc(var(--gutter) - 10px); bottom: 12px; border-width: 0 1px 1px 0; }
.arc-corners i:nth-child(4) { left: calc(var(--gutter) - 10px); bottom: 12px; border-width: 0 0 1px 1px; }

/* ---------- 状态栏 ---------- */
.arc-top { font: 11px/1 var(--f-mono, monospace); letter-spacing: .14em; color: #ffffffa8; text-transform: uppercase; }
.arc-status { display: inline-flex; align-items: center; gap: 10px; }
.arc-dot { width: 7px; height: 7px; border-radius: 50%; background: #62d98b; box-shadow: 0 0 10px #62d98b; animation: arc-dot 2.4s ease-in-out infinite; }
@keyframes arc-dot { 50% { opacity: .35; } }
.arc-sys { display: inline-flex; gap: 22px; }

/* ---------- 底部圆形按钮栏（Switch 式） ---------- */
.arc-dock { position: absolute; left: 50%; bottom: 18px; transform: translateX(-50%); display: flex; align-items: center; gap: 12px; }
.arc-dock-btn { position: relative; width: 44px; height: 44px; border-radius: 50%; border: 1px solid #ffffff2e; background: #0d0e0ecc;
  color: #e9e7e2; display: grid; place-items: center; cursor: pointer; padding: 0; transition: transform .15s ease, border-color .2s, background .2s, color .2s; }
.arc-dock-btn svg { width: 20px; height: 20px; fill: none; stroke: currentColor; stroke-width: 1.5; stroke-linecap: round; stroke-linejoin: round; }
.arc-dock-btn b { font: 700 12px/1 var(--f-mono, monospace); letter-spacing: .04em; }
.arc-dock-btn:hover, .arc-dock-btn:focus-visible { border-color: var(--accent); transform: translateY(-3px); outline: none;
  background: color-mix(in srgb, var(--accent) 22%, #0d0e0e); }
.arc-tip { position: absolute; bottom: calc(100% + 10px); left: 50%; transform: translate(-50%, 4px); white-space: nowrap;
  font: 11px/1 var(--f-mono, monospace); letter-spacing: .06em; color: #fff; padding: 6px 9px; border-radius: 6px;
  background: #000d; border: 1px solid #ffffff26; opacity: 0; pointer-events: none; transition: opacity .15s, transform .15s; }
.arc-dock-btn:hover .arc-tip, .arc-dock-btn:focus-visible .arc-tip { opacity: 1; transform: translate(-50%, 0); }
.arc-dock-sep { width: 1px; height: 22px; background: #ffffff26; margin: 0 4px; }
.arc-sound .on { display: none; }
.arc-sound[aria-pressed="true"] .on { display: inline; }
.arc-sound[aria-pressed="true"] .off { display: none; }
.arc-sound[aria-pressed="true"] { border-color: var(--accent); color: var(--accent); }

.arc-fade { position: absolute; inset: 0; background: #000; opacity: 0; pointer-events: none; transition: opacity .32s ease; }
.arc.is-leaving .arc-fade { opacity: 1; }

/* ---------- 背景二：后室 Level 0（极简梦核） ---------- */
/* 和网格共用同一块 canvas（.arc-grid），由 JS 按 data-bg 画不同的东西 */
.arc-vignette, .arc-grain { display: none; }
/* 暗角 + 上下压暗，保证白字可读，也像旧摄像机 */
.arc-vignette { position: absolute; inset: 0; pointer-events: none;
  background: radial-gradient(ellipse 85% 80% at 50% 42%, transparent 55%, #1a130570 100%),
    linear-gradient(#140f0480, #140f0400 16%, #140f0400 64%, #140f047a 86%, #140f04b8); }
.arc:not([data-bg="grid"]) .arc-info, .arc:not([data-bg="grid"]) .arc-top, .arc-page:has(.arc:not([data-bg="grid"])) .arc-header .brand {
  text-shadow: 0 1px 2px #2a1f0899, 0 2px 18px #2a1f08b0; }
.arc:not([data-bg="grid"]) .arc-desc { color: #f4efe0; }
/* 天花板很亮：状态栏改成深色小胶囊，像游戏 HUD */
.arc:not([data-bg="grid"]) .arc-status, .arc:not([data-bg="grid"]) .arc-sys { padding: 7px 11px; border-radius: 999px; background: #1c1606b3;
  -webkit-backdrop-filter: blur(8px); backdrop-filter: blur(8px); text-shadow: none; color: #fffbeee6; }
.arc:not([data-bg="grid"]) .arc-top { margin-top: -7px; }
.arc-page:has(.arc:not([data-bg="grid"])) .arc-header .brand .display { color: #fffbeecc; }
.arc:not([data-bg="grid"]) .arc-hint, .arc:not([data-bg="grid"]) .arc-meta { color: #fffbeecc; }
/* 胶片颗粒：用 transform 抖动，只走合成层 */
.arc-grain { position: absolute; inset: -120px; pointer-events: none; opacity: .07; background-size: 180px 180px;
  animation: arc-grain .7s steps(6) infinite; }
@keyframes arc-grain {
  0% { transform: translate(0, 0); } 17% { transform: translate(-46px, 31px); } 33% { transform: translate(38px, -52px); }
  50% { transform: translate(-21px, -17px); } 67% { transform: translate(57px, 44px); } 83% { transform: translate(-60px, 8px); } }
.arc-page:has(.arc:not([data-bg="grid"])) { background: #15110a; }
.arc:not([data-bg="grid"]) .arc-vignette, .arc:not([data-bg="grid"]) .arc-grain { display: block; }
.arc:not([data-bg="grid"]) .arc-spot, .arc:not([data-bg="grid"]) .arc-lamp,
.arc:not([data-bg="grid"]) .arc-bigtitle, .arc:not([data-bg="grid"]) .arc-glow { display: none; }
/* 地毯不反光：去掉倒影，地面光圈改成卡片落下的影子 */
.arc:not([data-bg="grid"]) .arc-frame { -webkit-box-reflect: none; box-shadow: 0 30px 70px #1a1203b0; }
.arc:not([data-bg="grid"]) .arc-floor { color: #0d0902; opacity: .55; }
.arc:not([data-bg="grid"]) .arc-shade { background: #1b1508; }
@media (prefers-reduced-motion: reduce) { .arc-grain { animation: none; } }

/* ---------- 背景三：三个 Blender 场景的渲染图，按作品切换 ---------- */
.arc-scenes { position: absolute; inset: 0; overflow: hidden; display: none; background: #0a0e0f; pointer-events: none; }
.arc-scene-layer { position: absolute; inset: -2.5%; opacity: 0; transition: opacity .9s ease; will-change: opacity, transform; }
.arc-scene-layer.is-on { opacity: 1; }
.arc-scene-layer img, .arc-scene-layer video { position: absolute; inset: 0; display: block; width: 100%; height: 100%; object-fit: cover; }
/* 视频开始播放后才盖到静帧上，静帧当海报 */
.arc-scene-layer video { opacity: 0; transition: opacity .7s ease; }
.arc-scene-layer.is-playing video { opacity: 1; }
.arc[data-bg="scenes"] .arc-scenes { display: block; }
.arc[data-bg="scenes"] .arc-grid { display: none; }
/* 场景是冷色的：暗角和文字阴影改成中性偏冷 */
.arc[data-bg="scenes"] .arc-vignette {
  background: radial-gradient(ellipse 85% 80% at 50% 42%, transparent 52%, #04080a80 100%),
    linear-gradient(#04080a8c, #04080a00 17%, #04080a00 60%, #04080a8f 84%, #04080acc); }
.arc[data-bg="scenes"] .arc-info, .arc[data-bg="scenes"] .arc-top { text-shadow: 0 1px 2px #02060899, 0 2px 18px #020608b8; }
.arc[data-bg="scenes"] .arc-status, .arc[data-bg="scenes"] .arc-sys { background: #060b0db8; }
.arc[data-bg="scenes"] .arc-shade { background: #050809; }
.arc[data-bg="scenes"] .arc-frame { box-shadow: 0 30px 80px #020506c0; }
.arc-page:has(.arc[data-bg="scenes"]) { background: #0a0e0f; }
.arc-page:has(.arc[data-bg="scenes"]) .arc-header .brand { text-shadow: 0 1px 2px #02060899, 0 2px 18px #020608b8; }

/* 顶栏导航和底部按钮栏重复，这页只留名字 */
.arc-header .nav { display: none; }

/* 以下是没启用固定画布时（竖屏手机、很小的窗口）的流式排版 */
/* 矮屏：收紧下方信息区 */
@media (max-height: 900px) and (min-width: 701px) {
  .arc:not(.is-staged) { --stack: 282px; --info-gap: 24px; --top-min: max(140px, 24svh); --cwv: 44vw; }
  .arc:not(.is-staged) .arc-title { margin: 8px 0 6px; font-size: clamp(28px, 3vw, 42px); }
  .arc:not(.is-staged) .arc-enter { margin-top: 14px; padding: 9px 18px; }
  .arc:not(.is-staged) .arc-hint { display: none; }
  .arc:not(.is-staged) .arc-bar { bottom: 80px; }
}

@media (max-width: 700px) {
  .arc:not(.is-staged) { --stack: 338px; --info-gap: 26px; --top-min: 140px; --cwv: 84vw; }
  .arc:not(.is-staged) .arc-nav { display: none; }
  .arc:not(.is-staged) .arc-title { font-size: 30px; }
  .arc:not(.is-staged) .arc-desc { font-size: 13px; }
  .arc:not(.is-staged) .arc-hint { display: none; }
  .arc:not(.is-staged) .arc-bar { bottom: 74px; }
  .arc:not(.is-staged) .arc-dock { gap: 8px; bottom: 14px; }
  .arc:not(.is-staged) .arc-dock-btn { width: 38px; height: 38px; }
  .arc:not(.is-staged) .arc-dock-btn svg { width: 17px; height: 17px; }
  .arc-tip, .arc-corners, .arc-lamp { display: none; }
  .arc-sys .arc-clock, .arc-role { display: none; }
}
@media (max-width: 700px) and (max-height: 700px) {
  .arc:not(.is-staged) { --stack: 280px; }
  .arc:not(.is-staged) .arc-desc { display: none; }
}
@media (prefers-reduced-motion: reduce) {
  .arc-card.is-focus .arc-ring { animation: none; }
  .arc-info > * { transition: none; }
}