.project-page {
  --arc-line: rgba(116, 163, 183, .25);
  --arc-dim: #82939d;
  background: #050b0f;
}
.project-page .reveal { opacity: 1; transform: none; }
.project-header { background: rgba(3, 9, 13, .92); border-bottom-color: var(--arc-line); }
.arc-page { width: min(1600px, 100%); margin: 0 auto; padding: var(--header-height) var(--gutter) 0; }

.arc-subnav {
  height: 4.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--arc-line);
  font-family: var(--display);
  font-size: .68rem;
  letter-spacing: .13em;
  text-transform: uppercase;
}
.arc-subnav a { color: #a7b4bb; transition: color .2s ease; }
.arc-subnav a:hover { color: var(--accent); }
.arc-subnav .back-link { color: var(--accent); }
.arc-subnav div { display: flex; align-self: stretch; gap: clamp(1.4rem, 3vw, 3.4rem); }
.arc-subnav div a { position: relative; display: flex; align-items: center; }
.arc-subnav div a:first-child { color: var(--accent); }
.arc-subnav div a:first-child::after { content: ""; position: absolute; right: 0; bottom: 0; left: 0; height: 1px; background: var(--accent); }

.arc-hero {
  min-height: 620px;
  display: grid;
  grid-template-columns: minmax(250px, .52fr) minmax(620px, 1.48fr);
  align-items: center;
  gap: clamp(2.5rem, 4.5vw, 6rem);
  padding: clamp(3.5rem, 6vw, 6.5rem) 0 3.5rem;
}
.arc-hero-copy { align-self: stretch; display: flex; flex-direction: column; justify-content: center; }
.arc-hero-copy h1 {
  margin: 0;
  font-family: var(--display);
  font-size: clamp(5rem, 7.1vw, 7.6rem);
  font-weight: 500;
  letter-spacing: .025em;
  line-height: .76;
  text-transform: uppercase;
}
.title-rule { width: 3.6rem; height: 2px; margin: 2.2rem 0 1.65rem; background: var(--accent); }
.arc-hero-copy h2 { margin: 0 0 1.35rem; font-family: var(--display); font-size: clamp(1.6rem, 2.2vw, 2.35rem); font-weight: 500; line-height: 1; text-transform: uppercase; }
.arc-hero-copy p { max-width: 390px; margin: 0; color: #aab6bd; font-size: .78rem; line-height: 1.75; }
.arc-actions { display: flex; gap: .8rem; margin: 2.2rem 0 2.8rem; }
.arc-actions .button { min-width: 0; padding: .72rem 1.1rem; font-size: .68rem; }
.arc-hero-copy small { color: #7d8d96; font-size: .68rem; }

.arc-app-frame { min-width: 0; overflow: hidden; border: 1px solid rgba(170, 197, 209, .38); background: #171b1d; box-shadow: 0 28px 90px rgba(0, 0, 0, .5); }
.window-bar { height: 2.45rem; display: flex; align-items: center; justify-content: space-between; padding: 0 .75rem; background: #171b1d; border-bottom: 1px solid rgba(255,255,255,.08); font-size: .7rem; }
.window-bar span { display: flex; align-items: center; gap: .5rem; }
.window-bar img { width: .9rem; height: .9rem; }
.window-bar i { width: 3.2rem; height: 1px; background: #727b80; box-shadow: 1.25rem 0 #727b80; }
.app-toolbar { width: 100%; height: auto; background: #303030; }
.app-canvas { width: 100%; aspect-ratio: 1415 / 793; object-fit: cover; }
.window-status { min-height: 2rem; display: flex; align-items: center; justify-content: space-between; padding: 0 .65rem; color: #89959b; background: #161a1c; font-family: var(--display); font-size: .62rem; }

.arc-content-frame { border: 1px solid var(--arc-line); }
.arc-row { display: grid; grid-template-columns: 9.2rem minmax(0, 1fr); border-bottom: 1px solid var(--arc-line); }
.arc-row:last-child { border-bottom: 0; }
.arc-label {
  position: relative;
  margin: 0;
  padding: 2rem 1rem;
  color: var(--accent);
  font-family: var(--display);
  font-size: 1.05rem;
  font-weight: 500;
  letter-spacing: .05em;
  line-height: .9;
  text-transform: uppercase;
}
.arc-label::after { content: ""; display: block; width: 1.5rem; height: 1px; margin-top: .75rem; background: var(--accent); }

.overview-grid { display: grid; grid-template-columns: repeat(4, 1fr); }
.overview-grid article { min-height: 10.5rem; padding: 2rem clamp(1rem, 2.5vw, 2.5rem); border-left: 1px solid var(--arc-line); }
.line-icon { width: auto; height: 2.8rem; object-fit: contain; object-position: left center; }
.overview-grid h3, .workflow-grid h3, .feature-grid h3, .download-content h3 { margin: .75rem 0 .35rem; font-family: var(--display); font-size: .92rem; font-weight: 500; letter-spacing: .06em; text-transform: uppercase; }
.overview-grid p, .workflow-grid p, .feature-grid p, .download-content p { margin: 0; color: var(--arc-dim); font-size: .7rem; line-height: 1.65; }

.workflow-grid { display: grid; grid-template-columns: repeat(4, 1fr); margin: 0; padding: 0; list-style: none; }
.workflow-grid li { position: relative; min-height: 12.5rem; padding: 2rem clamp(1rem, 2vw, 2rem); border-left: 1px solid var(--arc-line); }
.workflow-icon { width: auto; height: 3.6rem; object-fit: contain; object-position: left center; }
.flow-arrow { position: absolute; top: 2.8rem; left: -1.2rem; color: var(--accent); font-size: 1.4rem; }

.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); }
.feature-grid article { min-width: 0; padding: 2rem clamp(1rem, 2vw, 2rem) 2.4rem; border-left: 1px solid var(--arc-line); border-bottom: 1px solid var(--arc-line); }
.feature-grid article:nth-last-child(-n+3) { border-bottom: 0; }
.feature-grid h3 { display: flex; align-items: center; gap: .55rem; margin: 0 0 .4rem; font-size: 1.05rem; }
.feature-grid h3 img { flex: 0 0 auto; width: 1.9rem; height: 1.9rem; object-fit: contain; }
.feature-grid p { min-height: 3.5rem; }
.feature-visual { width: 100%; height: 10.5rem; margin-top: 1rem; object-fit: contain; object-position: left center; }
.feature-visual-open { object-position: center; }

.shortcut-strip { display: grid; grid-template-columns: repeat(10, minmax(0, 1fr)); align-items: center; padding: 2rem 1rem; }
.shortcut-strip div { min-width: 0; padding: 0 .35rem; text-align: center; }
.shortcut-strip kbd { display: block; padding: .45rem .25rem; border: 1px solid rgba(25,189,242,.45); border-radius: .2rem; color: var(--accent); background: #0c151a; font-family: var(--display); font-size: .68rem; white-space: nowrap; }
.shortcut-strip span { display: block; margin-top: .55rem; color: var(--arc-dim); font-size: .6rem; white-space: nowrap; }

.download-content { display: grid; grid-template-columns: 5rem 1fr auto; align-items: center; gap: 2rem; padding: 2.2rem; }
.download-mark { color: var(--accent); font-family: var(--display); font-size: 5rem; line-height: 1; }
.download-content h3 { margin-top: 0; font-size: 1.3rem; }
.download-content ul { margin: .8rem 0 0; padding: 0; color: #9fadb4; font-size: .68rem; line-height: 1.8; list-style: none; }
.download-content li::before { content: "✓"; margin-right: .65rem; color: var(--accent); }
.download-actions { display: flex; flex-direction: column; align-items: stretch; gap: 1.25rem; text-align: center; }
.download-actions .button { min-width: 15rem; padding-block: .75rem; font-size: .68rem; }
.download-actions > a:last-child { color: var(--accent); font-family: var(--display); font-size: .64rem; letter-spacing: .08em; text-transform: uppercase; }

@media (max-width: 1050px) {
  .arc-hero { grid-template-columns: 1fr; }
  .arc-hero-copy { max-width: 620px; }
  .arc-app-frame { width: 100%; }
  .arc-row { grid-template-columns: 7.2rem minmax(0,1fr); }
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
  .feature-grid article:nth-last-child(-n+3) { border-bottom: 1px solid var(--arc-line); }
  .feature-grid article:nth-last-child(-n+2) { border-bottom: 0; }
  .shortcut-strip { grid-template-columns: repeat(5, 1fr); gap: 1rem 0; }
}

@media (max-width: 720px) {
  .project-header { backdrop-filter: none; }
  .project-page .site-nav { background: #060a0d; }
  .arc-page { padding-inline: var(--gutter); }
  .arc-subnav { height: auto; align-items: flex-start; padding: 1.2rem 0; }
  .arc-subnav div { display: none; }
  .arc-hero { min-height: auto; grid-template-columns: 1fr; padding: 3.5rem 0; }
  .arc-hero-copy h1 { font-size: clamp(5rem, 24vw, 7.5rem); }
  .arc-actions { display: grid; grid-template-columns: 1fr; max-width: 18rem; }
  .arc-app-frame { margin-top: .5rem; }
  .window-status { display: none; }
  .arc-row { display: block; }
  .arc-label { padding: 1.5rem 1rem .5rem; }
  .overview-grid, .workflow-grid, .feature-grid { grid-template-columns: 1fr; }
  .overview-grid article, .workflow-grid li, .feature-grid article { min-height: 0; padding: 1.5rem; border-left: 0; border-bottom: 1px solid var(--arc-line); }
  .feature-grid article:nth-last-child(-n+2) { border-bottom: 1px solid var(--arc-line); }
  .feature-grid article:last-child { border-bottom: 0; }
  .flow-arrow { display: none; }
  .feature-grid p { min-height: 0; }
  .shortcut-strip { grid-template-columns: repeat(2, 1fr); padding: 1.5rem 1rem; }
  .download-content { grid-template-columns: 1fr; padding: 1.5rem; }
  .download-mark { font-size: 4rem; }
  .download-actions { align-items: stretch; }
  .download-actions .button { min-width: 0; }
}