:root {
  --bg: #0e141b;
  --panel: #171d25;
  --line: #2a3a4a;
  --text: #c7d5e0;
  --muted: #8a9bab;
  --heading: #ffffff;
  --accent: #1a9fff;
  --accent-text: #0e141b;
  --max: 1080px;
  --font: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", "Noto Sans JP", sans-serif;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: 64px; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.55 var(--font);
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent); text-decoration: none; }
a:hover, a:focus-visible { text-decoration: underline; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

h1, h2, h3 { color: var(--heading); font-weight: 600; line-height: 1.2; margin: 0; }
h1 { font-size: 2.25rem; letter-spacing: -0.01em; }
h2 { font-size: 1.5rem; margin-bottom: 1.5rem; }
h3 { font-size: 1.0625rem; }
p { margin: 0 0 1em; }
p:last-child { margin-bottom: 0; }
code { font: 0.9em var(--mono); background: var(--panel); border: 1px solid var(--line); padding: 0.05em 0.35em; }
b { color: var(--heading); font-weight: 600; }

.wrap { max-width: var(--max); margin: 0 auto; padding: 0 20px; }

/* nav */

.nav {
  position: sticky; top: 0; z-index: 10;
  background: var(--bg);
  border-bottom: 1px solid var(--line);
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 56px; gap: 16px; }
.wordmark { display: flex; align-items: center; gap: 12px; min-width: 0; color: var(--heading); font-weight: 600; }
.wordmark-logo { display: block; width: 28px; height: 28px; flex-shrink: 0; }
.wordmark-text { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.wordmark-sub { color: var(--muted); font-weight: 400; }
.wordmark:hover { text-decoration: none; }
.nav-links { display: flex; align-items: center; gap: 20px; flex-shrink: 0; }
.nav-links a { color: var(--text); }
.nav-links a:hover { color: var(--heading); text-decoration: none; }

/* buttons */

.btn {
  display: inline-block;
  padding: 11px 20px;
  background: var(--accent);
  color: var(--accent-text);
  font: inherit; font-weight: 600;
  border: 1px solid var(--accent);
  cursor: pointer;
  text-decoration: none;
}
.btn:hover, .btn:focus-visible { text-decoration: none; background: #4db5ff; border-color: #4db5ff; }
.btn:disabled { opacity: 0.35; cursor: default; }
.btn[hidden] { display: none; }
.btn:disabled:hover { background: var(--accent); border-color: var(--accent); }
.btn-ghost { background: transparent; color: var(--heading); border-color: var(--line); }
.btn-ghost:hover, .btn-ghost:focus-visible { background: var(--panel); border-color: var(--muted); }
.btn-ghost:disabled:hover { background: transparent; border-color: var(--line); }
.btn-small { padding: 7px 14px; }
.nav-links .btn-small { color: var(--accent-text); }
.nav-links .btn-small:hover { color: var(--accent-text); }

/* sections */

section { padding: 64px 0; border-bottom: 1px solid var(--line); }
section:last-of-type { border-bottom: 0; }
.lead { font-size: 1.125rem; max-width: 60ch; }
.aside { color: var(--muted); font-size: 0.9375rem; }

/* hero */

.hero { text-align: center; padding-top: 48px; }
.hero .lead { margin: 12px auto 24px; }
.hero h1 { margin-top: 32px; }
.cta { display: flex; justify-content: center; gap: 12px; flex-wrap: wrap; }
.credit { margin: 8px 0 0; color: var(--muted); font-size: 0.75rem; }
.steps + .credit { margin-top: 20px; }

.deck { position: relative; max-width: 860px; margin: 0 auto; aspect-ratio: 1024 / 414; }
.deck-outline { display: block; width: 100%; height: auto; opacity: 0.55; }
.deck-screen {
  position: absolute;
  left: 23.68%; top: 8.94%; width: 52.79%; height: 82.09%;
}

/* screenshot placeholders */

.shot {
  display: flex; align-items: center; justify-content: center; text-align: center;
  width: 100%; height: 100%;
  padding: 16px;
  color: var(--muted); font-size: 0.875rem;
  background: var(--panel);
  border: 1px dashed var(--line);
}
.shot-hero { font-size: 0.8125rem; }
.shot-step { aspect-ratio: 16 / 10; height: auto; min-width: 0; }
.step > * { min-width: 0; }
.step img, .deck-screen img { display: block; width: 100%; height: 100%; object-fit: cover; }

/* how it works */

.steps { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.steps li { border: 1px solid var(--line); background: var(--panel); overflow: hidden; }
.steps p { font-size: 0.9375rem; color: var(--text); margin: 0; }
.step-text img.btn-icon { display: inline-block; width: auto; height: 1em; vertical-align: -0.1em; margin: 0 0.1em; }
.step-shot { aspect-ratio: 16 / 10; overflow: hidden; cursor: zoom-in; border-bottom: 1px solid var(--line); }
.step-shot img { display: block; width: 100%; height: 100%; object-fit: cover; transition: transform 0.25s ease; }
.step-shot:hover img { transform: scale(1.04); }
.step-body { padding: 16px 20px 20px; }
.step-head { display: flex; align-items: center; gap: 10px; margin-bottom: 6px; }
.step-head h3 { margin: 0; font-size: 1rem; }
.step-head h3 b { color: var(--heading); font-weight: 600; margin-right: 2px; }
.num {
  display: inline-flex; align-items: center; justify-content: center;
  width: 32px; height: 32px; flex: 0 0 auto;
  border: 1px solid var(--line); color: var(--heading); font-weight: 600;
}
.num img { display: block; width: 18px; height: 18px; }

.lightbox {
  position: fixed; inset: 0; z-index: 100; padding: 40px;
  display: flex; align-items: center; justify-content: center; flex-direction: column;
  background: rgba(6, 9, 13, 0.92);
  opacity: 0; pointer-events: none; transition: opacity 0.2s ease;
}
.lightbox.open { opacity: 1; pointer-events: auto; }
.lightbox img, .lightbox video { max-width: 88vw; max-height: 80vh; border: 1px solid var(--line); display: block; }
.lightbox img[hidden], .lightbox video[hidden] { display: none; }
.lightbox-description { color: var(--heading); text-align: center; max-width: 60ch; margin-top: 18px; font-size: 1rem; }
.lightbox-description[hidden] { display: none; }
.lightbox-caption { color: var(--muted); text-align: center; margin-top: 6px; font-size: 0.875rem; }
.lightbox-close, .lightbox-nav {
  position: absolute; top: 20px; right: 24px;
  width: 40px; height: 40px; display: flex; align-items: center; justify-content: center;
  background: var(--panel); border: 1px solid var(--line); color: var(--heading);
  font-size: 1.5rem; line-height: 1; cursor: pointer;
}
.lightbox-close:hover, .lightbox-nav:hover { border-color: var(--muted); }
.lightbox-nav { top: 50%; right: auto; transform: translateY(-50%); }
.lightbox-prev { left: 24px; }
.lightbox-next { right: 24px; }
.lightbox-nav[hidden] { display: none; }

.modal {
  position: fixed; inset: 0; z-index: 100; padding: 20px;
  display: flex; align-items: center; justify-content: center;
  background: rgba(6, 9, 13, 0.92);
  opacity: 0; pointer-events: none; transition: opacity 0.2s ease;
}
.modal.open { opacity: 1; pointer-events: auto; }
.modal-card {
  position: relative; width: 100%; max-width: 560px;
  background: var(--panel); border: 1px solid var(--line);
  padding: 32px; text-align: center;
}
.modal-shot { display: block; width: 100%; aspect-ratio: 1057 / 427; object-fit: contain; margin-bottom: 24px; }
.modal-card h3 { font-size: 1.5rem; margin-bottom: 12px; }
.modal-card p { font-size: 1rem; }
.modal-cta { display: block; width: 100%; margin-top: 20px; padding: 15px 20px; font-size: 1.125rem; }
.modal-close {
  position: absolute; top: 12px; right: 12px;
  width: 32px; height: 32px; display: flex; align-items: center; justify-content: center;
  background: transparent; border: 1px solid var(--line); color: var(--heading);
  font-size: 1.25rem; line-height: 1; cursor: pointer;
}
.modal-close:hover { border-color: var(--muted); }

/* features */

.grid { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(2, 1fr); gap: 1px; background: var(--line); border: 1px solid var(--line); }
.grid li { background: var(--bg); padding: 22px; }
.grid h3 { margin-bottom: 6px; }
.grid p { font-size: 0.9375rem; }
.feature-icon {
  display: inline-flex; align-items: center; justify-content: center;
  width: 40px; height: 40px;
  border: 1px solid var(--line); margin-bottom: 12px;
}
.feature-icon img { display: block; width: 22px; height: 22px; }

/* install */

.stepper { border: 1px solid var(--line); }
.stepper-tabs { display: flex; border-bottom: 1px solid var(--line); overflow-x: auto; }
.stepper-tabs button {
  flex: 1 0 auto;
  padding: 14px 16px;
  background: var(--panel); color: var(--muted);
  font: inherit; font-size: 0.9375rem;
  border: 0; border-right: 1px solid var(--line); border-bottom: 2px solid transparent;
  cursor: pointer; white-space: nowrap;
}
.stepper-tabs button:last-child { border-right: 0; }
.stepper-tabs button b { color: inherit; margin-right: 6px; }
.stepper-tabs button:hover { color: var(--heading); }
.stepper-tabs button[aria-selected="true"] { background: var(--bg); color: var(--heading); border-bottom-color: var(--accent); }
.stepper-tabs button:focus-visible { outline-offset: -2px; }

.step { display: grid; grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr); gap: 32px; padding: 32px; border: 0; }
.step[hidden] { display: none; }
.step-text h3 { margin-bottom: 10px; }
.step-text .btn { margin-bottom: 1em; }
.step-text table { border-collapse: collapse; width: 100%; margin: 0 0 1em; font-size: 0.9375rem; }
.step-text td { padding: 6px 0; border-bottom: 1px solid var(--line); }
.step-text td:last-child { color: var(--muted); padding-left: 24px; text-align: right; }

.frames { position: relative; }

.frames-shots { position: relative; aspect-ratio: 16 / 10; }
.frames-shots img {
  position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover;
  opacity: 0; transition: opacity 0.3s ease;
}
.frames-shots img.active { opacity: 1; }
html:not(.js) .frames-shots { position: static; aspect-ratio: auto; }
html:not(.js) .frames-shots img { position: static; opacity: 1; margin-bottom: 12px; }
html:not(.js) .frames-shots img:last-child { margin-bottom: 0; }

.shot-ping {
  position: absolute;
  width: 14px; height: 14px;
  margin: -7px 0 0 -7px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 3px rgba(26, 159, 255, 0.35);
  pointer-events: none;
}
.shot-ping[hidden] { display: none; }
.shot-ping::before {
  content: "";
  position: absolute; inset: -6px;
  border-radius: 50%;
  border: 2px solid var(--accent);
  animation: shot-ping-pulse 1.8s ease-out infinite;
}
@keyframes shot-ping-pulse {
  from { transform: scale(0.6); opacity: 0.9; }
  to { transform: scale(2.6); opacity: 0; }
}
html:not(.js) .shot-ping { display: none; }
@media (prefers-reduced-motion: reduce) {
  .shot-ping::before { animation: none; opacity: 0.5; }
}

.step-list { list-style: none; margin: 0 0 1em; padding: 0; }
.step-list li {
  display: flex; align-items: flex-start; gap: 14px;
  padding: 10px 12px; margin: 0 -12px 2px;
  border: 1px solid transparent; cursor: pointer;
  transition: border-color 0.2s ease, background 0.2s ease;
}
.step-list li:last-child { margin-bottom: 0; }
.step-list li.active { border-color: var(--line); background: var(--bg); }
.step-num {
  display: inline-flex; align-items: center; justify-content: center;
  flex: 0 0 auto; width: 26px; height: 26px; margin-top: 1px;
  border: 1px solid var(--line); color: var(--muted); font-weight: 600; font-size: 0.8125rem;
  transition: border-color 0.2s ease, background 0.2s ease, color 0.2s ease;
}
.step-list li.active .step-num { border-color: var(--accent); background: var(--accent); color: var(--accent-text); }

.stepper-nav { display: flex; align-items: center; padding: 16px 32px; border-top: 1px solid var(--line); }
.stepper-nav [data-dir="1"] { margin-left: auto; }

html:not(.js) .stepper-tabs, html:not(.js) .stepper-nav { display: none; }
html:not(.js) .step + .step { border-top: 1px solid var(--line); }

.install .aside { margin-top: 24px; max-width: 70ch; }

/* gallery */

.gallery-grid { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.gallery-grid .step-shot { border: 1px solid var(--line); background: var(--panel); }
.gallery-video {
  aspect-ratio: 16 / 10; overflow: hidden; cursor: zoom-in;
  border: 1px solid var(--line); background: var(--panel);
}
.gallery-video video { display: block; width: 100%; height: 100%; object-fit: cover; transition: transform 0.25s ease; }
.gallery-video:hover video { transform: scale(1.04); }

/* faq */

.faq details { border-top: 1px solid var(--line); }
.faq details:last-child { border-bottom: 1px solid var(--line); }
.faq summary {
  cursor: pointer; list-style: none;
  padding: 16px 0; padding-right: 32px;
  color: var(--heading); font-weight: 600;
  position: relative;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "+"; position: absolute; right: 4px; top: 14px;
  color: var(--muted); font-weight: 400; font-size: 1.25rem; line-height: 1.2;
}
.faq details[open] summary::after { content: "−"; }
.faq details p { padding: 0 0 18px; max-width: 72ch; }

/* footer */

.footer { border-top: 1px solid var(--line); padding: 32px 0 48px; color: var(--muted); font-size: 0.875rem; }
.footer a { color: var(--text); }
.footer p { max-width: 80ch; }

/* responsive */

@media (max-width: 900px) {
  .steps { grid-template-columns: 1fr; }
  .step { grid-template-columns: minmax(0, 1fr); gap: 24px; padding: 24px; }
  .stepper-nav { padding: 16px 24px; }
  .gallery-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 600px) {
  h1 { font-size: 1.75rem; }
  section { padding: 48px 0; }
  .nav-links { gap: 14px; font-size: 0.9375rem; }
  .nav-links a:not(.btn):nth-child(-n+5) { display: none; }
  .wordmark-sub { display: none; }
  .steps, .grid { grid-template-columns: 1fr; }
  .gallery-grid { grid-template-columns: 1fr; }
  .deck-outline { display: none; }
  .deck { aspect-ratio: auto; }
  .deck-screen { position: static; width: 100%; height: auto; }
  .shot-hero { aspect-ratio: 16 / 10; }
  .stepper-tabs button b { margin-right: 0; }
  .stepper-tabs button span { display: none; }
}