:root {
  --ink: #101114;
  --muted: #666a73;
  --line: #e6e7eb;
  --soft: #f5f6f8;
  --cyan: #25f4ee;
  --pink: #fe2c55;
  --radius: 22px;
  color-scheme: light;
  font-family: Inter, "Noto Sans JP", "Hiragino Kaku Gothic ProN", system-ui, sans-serif;
  font-synthesis: none;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; color: var(--ink); background: #fff; line-height: 1.65; }
button, input, select, textarea { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
a { color: inherit; }
[hidden] { display: none !important; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0; }
.skip-link { position: fixed; left: 12px; top: -60px; z-index: 99; padding: 10px 14px; background: #fff; border: 2px solid var(--ink); border-radius: 8px; }
.skip-link:focus { top: 12px; }

.site-header { height: 76px; display: flex; align-items: center; justify-content: space-between; padding: 0 clamp(20px, 5vw, 72px); border-bottom: 1px solid rgba(230,231,235,.8); background: rgba(255,255,255,.92); backdrop-filter: blur(16px); position: relative; z-index: 10; }
.brand { display: inline-flex; align-items: center; gap: 10px; color: var(--ink); text-decoration: none; font-weight: 850; font-size: 20px; letter-spacing: -.04em; }
.brand-mark { display: grid; place-items: center; width: 36px; height: 36px; border-radius: 11px; color: #fff; background: #101114; font-size: 19px; box-shadow: -3px -2px 0 var(--cyan), 3px 2px 0 var(--pink); }
.language-picker select { appearance: none; min-width: 116px; border: 1px solid var(--line); border-radius: 999px; padding: 9px 32px 9px 14px; color: var(--ink); background: #fff url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12'%3E%3Cpath d='m2 4 4 4 4-4' fill='none' stroke='%23101114' stroke-width='1.7'/%3E%3C/svg%3E") no-repeat right 12px center; cursor: pointer; }

.hero { min-height: 640px; display: grid; place-items: center; padding: 78px 20px 84px; position: relative; overflow: hidden; border-bottom: 1px solid var(--line); }
.hero-content { width: min(820px, 100%); text-align: center; position: relative; z-index: 1; }
.hero-orb { position: absolute; width: 380px; height: 380px; border-radius: 50%; filter: blur(110px); opacity: .15; pointer-events: none; }
.hero-orb-a { left: -150px; top: 25%; background: var(--cyan); }
.hero-orb-b { right: -150px; bottom: 10%; background: var(--pink); }
.eyebrow, .section-kicker { display: inline-flex; align-items: center; gap: 8px; font-size: 12px; font-weight: 800; letter-spacing: .16em; text-transform: uppercase; }
.dot { width: 8px; height: 8px; border-radius: 50%; }
.dot-tiktok { background: var(--cyan); box-shadow: 0 0 0 3px rgba(37,244,238,.16); }
.dot-x { background: var(--pink); box-shadow: 0 0 0 3px rgba(254,44,85,.12); }
.plus { color: #9b9ea5; }
.hero h1 { margin: 20px auto 12px; max-width: 760px; font-size: clamp(38px, 7vw, 74px); line-height: 1.05; letter-spacing: -.065em; }
.hero-subtitle { margin: 0 auto 34px; max-width: 620px; color: var(--muted); font-size: clamp(16px, 2vw, 19px); }
.download-form { display: grid; grid-template-columns: minmax(0,1fr) auto; gap: 12px; align-items: stretch; }
.url-field { min-width: 0; display: flex; align-items: center; gap: 10px; padding: 7px 8px 7px 18px; border: 1.5px solid #d8dae0; border-radius: 16px; background: #fff; box-shadow: 0 12px 40px rgba(16,17,20,.07); transition: border-color .2s, box-shadow .2s; }
.url-field:focus-within { border-color: var(--ink); box-shadow: 0 14px 50px rgba(16,17,20,.1), -3px 0 0 rgba(37,244,238,.45), 3px 0 0 rgba(254,44,85,.25); }
.url-field svg { width: 21px; flex: 0 0 auto; fill: #9699a1; }
.url-field input { width: 100%; min-width: 0; border: 0; outline: 0; padding: 13px 0; color: var(--ink); background: transparent; }
.url-field input::placeholder { color: #a2a5ac; }
.paste-button, .back-button { border: 0; background: transparent; color: var(--muted); font-weight: 750; cursor: pointer; }
.paste-button { padding: 9px 12px; border-radius: 9px; white-space: nowrap; }
.paste-button:hover { color: var(--ink); background: var(--soft); }
.primary-button, .secondary-button { min-height: 54px; border: 0; border-radius: 16px; display: inline-flex; align-items: center; justify-content: center; gap: 13px; padding: 0 24px; text-decoration: none; font-weight: 800; cursor: pointer; transition: transform .18s, opacity .18s, box-shadow .18s; }
.primary-button { color: #fff; background: var(--ink); box-shadow: -3px -2px 0 var(--cyan), 3px 2px 0 var(--pink); }
.primary-button:hover { transform: translateY(-2px); box-shadow: -4px -3px 0 var(--cyan), 4px 3px 0 var(--pink), 0 12px 25px rgba(16,17,20,.16); }
.primary-button:disabled { opacity: .55; cursor: wait; transform: none; }
.secondary-button { min-height: 46px; background: var(--soft); color: var(--ink); border: 1px solid var(--line); }
.support-note { margin: 16px 0 0; color: #878a92; font-size: 13px; }
.form-message { min-height: 26px; margin-top: 12px; color: #b51f3d; font-size: 14px; font-weight: 650; }
.form-message.success { color: #087e62; }

.content-shell, .info-section { width: min(1120px, calc(100% - 40px)); margin-inline: auto; }
.result-view { min-height: 620px; padding: 44px 0 84px; }
.back-button { margin: 0 0 26px; padding: 7px 0; }
.status-card { padding: 48px 24px; text-align: center; border: 1px solid var(--line); border-radius: var(--radius); background: var(--soft); }
.status-card .spinner { width: 36px; height: 36px; margin: 0 auto 16px; border: 3px solid #dddfe4; border-top-color: var(--ink); border-radius: 50%; animation: spin .8s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }
.result-header { display: flex; justify-content: space-between; gap: 20px; align-items: end; margin-bottom: 24px; }
.result-header h1 { margin: 0; font-size: clamp(28px, 4vw, 46px); letter-spacing: -.045em; }
.source-link { color: var(--muted); text-underline-offset: 4px; font-size: 14px; }
.video-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(min(100%, 245px), 1fr)); gap: 20px; }
.video-card { overflow: hidden; border: 1px solid var(--line); border-radius: var(--radius); background: #fff; box-shadow: 0 16px 45px rgba(16,17,20,.06); }
.video-cover { aspect-ratio: 16/11; width: 100%; display: block; object-fit: cover; background: #eceef2; }
.video-card-body { padding: 19px; }
.platform-badge { display: inline-flex; border-radius: 999px; padding: 4px 9px; color: #fff; background: var(--ink); font-size: 11px; font-weight: 800; letter-spacing: .08em; }
.video-title { margin: 11px 0 5px; overflow: hidden; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; font-size: 15px; line-height: 1.5; }
.video-author { color: var(--muted); font-size: 13px; }
.quality-list { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 16px; }
.quality-link { min-height: 40px; display: inline-flex; align-items: center; justify-content: center; flex: 1 1 90px; padding: 7px 12px; border-radius: 11px; color: #fff; background: var(--ink); text-decoration: none; font-weight: 780; font-size: 13px; }
.quality-link:hover { box-shadow: -2px -1px 0 var(--cyan), 2px 1px 0 var(--pink); }
.retry-row { margin-top: 18px; text-align: center; }

.info-section { padding-block: 92px; border-bottom: 1px solid var(--line); }
.info-section h2 { margin: 10px 0 0; font-size: clamp(29px, 4vw, 48px); line-height: 1.15; letter-spacing: -.045em; }
.section-kicker { color: var(--pink); }
.split-section { display: grid; grid-template-columns: .85fr 1.15fr; gap: clamp(40px, 8vw, 110px); align-items: center; }
html[lang="ja"] .split-section h2 { white-space: nowrap; font-size: clamp(24px, 3.2vw, 42px); }
.split-section > p { margin: 0; color: var(--muted); font-size: 18px; }
.steps-grid { list-style: none; padding: 0; margin: 44px 0 0; display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.steps-grid li { min-height: 170px; padding: 25px; border-radius: var(--radius); background: var(--soft); }
.steps-grid li > span { color: var(--pink); font: 800 13px/1 monospace; letter-spacing: .1em; }
.steps-grid p { margin: 42px 0 0; font-weight: 720; }
.faq-list { margin-top: 42px; }
.faq-list details { border-top: 1px solid var(--line); }
.faq-list details:last-child { border-bottom: 1px solid var(--line); }
.faq-list summary { list-style: none; display: flex; justify-content: space-between; gap: 20px; padding: 23px 0; cursor: pointer; font-weight: 760; }
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary span { font-size: 22px; transition: transform .2s; }
.faq-list details[open] summary span { transform: rotate(45deg); }
.faq-list details p { max-width: 800px; margin: -6px 0 23px; color: var(--muted); }

.document-page, .contact-page, .empty-page { padding-block: 76px 110px; }
.document-page header, .contact-page header { max-width: 780px; margin-bottom: 60px; }
.document-page h1, .contact-page h1 { margin: 10px 0; font-size: clamp(38px, 6vw, 62px); line-height: 1.08; letter-spacing: -.055em; }
.document-page header p, .contact-page header p { color: var(--muted); font-size: 18px; }
.document-page section { max-width: 820px; margin-top: 42px; }
.document-page section h2 { font-size: 21px; }
.document-page section p { color: #4f535b; white-space: pre-line; }
.contact-form { max-width: 760px; display: grid; gap: 22px; }
.contact-form label { display: grid; gap: 8px; font-weight: 720; }
.contact-form small { color: var(--muted); font-weight: 500; }
.field-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.contact-form input, .contact-form select, .contact-form textarea { width: 100%; border: 1px solid #d7d9df; border-radius: 13px; padding: 13px 15px; outline: 0; resize: vertical; }
.contact-form input:focus, .contact-form select:focus, .contact-form textarea:focus { border-color: var(--ink); box-shadow: 0 0 0 3px rgba(37,244,238,.2); }
.checkbox-row { grid-template-columns: auto 1fr !important; align-items: start; font-weight: 500 !important; }
.checkbox-row input { width: 18px; margin-top: 4px; }
.contact-form .primary-button { width: fit-content; min-width: 160px; }
.turnstile-box { min-height: 65px; }
.empty-page { min-height: 600px; text-align: center; }
.error-code { font-size: 96px; font-weight: 900; letter-spacing: -.08em; color: #e8e9ed; }

.ad-slot { min-height: 100px; margin: 38px auto 0; display: grid; place-items: center; border: 1px dashed #dfe1e6; border-radius: 14px; color: #9a9da5; font-size: 10px; letter-spacing: .12em; text-transform: uppercase; }
.site-footer { padding: 54px 20px 26px; background: #101114; color: #fff; }
.footer-inner { width: min(1120px, 100%); margin: auto; display: grid; grid-template-columns: 1fr auto; gap: 36px; }
.footer-brand { color: #fff; }
.footer-brand .brand-mark { background: #fff; color: #101114; }
.footer-inner > div > p { max-width: 550px; color: #9fa2aa; font-size: 13px; }
.footer-inner nav { display: flex; flex-wrap: wrap; align-content: start; justify-content: end; gap: 12px 22px; font-size: 13px; }
.footer-inner nav a, .footer-inner nav button { border: 0; padding: 0; color: #c8cad0; background: transparent; text-decoration: none; cursor: pointer; }
.footer-inner nav a:hover, .footer-inner nav button:hover { color: #fff; text-decoration: underline; }
.copyright { grid-column: 1/-1; margin: 22px 0 0; padding-top: 22px; border-top: 1px solid #292b30; color: #777b84; font-size: 12px; }

@media (max-width: 760px) {
  .site-header { height: 66px; padding-inline: 18px; }
  .brand { font-size: 18px; }
  .brand-mark { width: 32px; height: 32px; }
  .language-picker select { min-width: 100px; max-width: 115px; }
  .hero { min-height: 650px; padding-top: 62px; }
  .download-form { grid-template-columns: 1fr; }
  .download-form > .primary-button { width: 100%; }
  .url-field { padding-left: 14px; }
  .paste-button { padding-inline: 7px; }
  .split-section, .field-grid { grid-template-columns: 1fr; }
  html[lang="ja"] .split-section h2 { font-size: clamp(22px, 7vw, 32px); }
  .steps-grid { grid-template-columns: 1fr; }
  .steps-grid li { min-height: 130px; }
  .steps-grid p { margin-top: 28px; }
  .info-section { padding-block: 70px; }
  .result-header { display: block; }
  .source-link { display: inline-block; margin-top: 10px; }
  .footer-inner { grid-template-columns: 1fr; }
  .footer-inner nav { justify-content: start; }
  .copyright { grid-column: auto; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
}