/* The public introduction uses the same controls and semantic colours as the app. */
.welcome-body { line-height: 1.65; }
.welcome-header, .welcome-main, .welcome-footer { width: min(1180px, calc(100% - 80px)); margin-inline: auto; }
.welcome-header { display: flex; align-items: center; justify-content: space-between; padding-block: 22px; border-bottom: 1px solid var(--border); }
.welcome-brand { margin: 0; font-size: 27px; gap: 6px; }
.welcome-brand .site-brand-logo { width: 56px; height: 56px; }
.welcome-nav { display: flex; align-items: center; gap: 32px; font-size: var(--font-small); font-weight: 600; }
.welcome-nav-feature:hover, .welcome-explore:hover { color: var(--primary); }
.welcome-skip { position: absolute; top: 12px; left: 12px; z-index: var(--layer-popover); padding: 12px 20px; background: var(--surface); border-radius: var(--radius-control); transform: translateY(-180%); }
.welcome-skip:focus { transform: none; }
.welcome-hero { display: grid; grid-template-columns: 1.12fr 1fr; align-items: center; gap: clamp(32px, 6vw, 80px); padding-block: 84px 96px; }
.welcome-intro { animation: welcome-arrive .8s ease-out both; }
.welcome-eyebrow { display: flex; align-items: center; gap: 9px; color: var(--primary); font-size: 12px; font-weight: 700; letter-spacing: 1.4px; text-transform: uppercase; margin: 0 0 20px; }
.welcome-eyebrow svg { width: 18px; height: 18px; }
.welcome-hero h1 { font: 800 clamp(2.6rem, 4.25vw, 3.7rem)/1.14 var(--font-heading); letter-spacing: -2.5px; margin: 0 0 25px; }
.welcome-hero h1 em { color: var(--primary); font-style: normal; }
.welcome-lead { max-width: 490px; margin: 0; font-size: 17px; color: var(--text-muted); line-height: 1.85; }
.welcome-lead strong { color: var(--text); font-weight: 600; }
.welcome-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 24px; margin-top: 32px; }
.welcome-explore { display: inline-flex; align-items: center; gap: 12px; min-height: 44px; font-size: var(--font-small); font-weight: 600; }
.welcome-explore span { font-size: 20px; }
.welcome-note { margin-top: 20px; color: var(--text-muted); font-size: 12px; }
.welcome-preview { position: relative; min-width: 0; margin: 0; padding: 30px; background: var(--surface); border: 1px solid var(--border); border-radius: 26px; box-shadow: var(--shadow); transform: rotate(2deg); animation: welcome-settle 1.1s cubic-bezier(.2,.75,.2,1) both; }
.welcome-preview-top { display: flex; align-items: center; gap: 14px; padding-bottom: 24px; border-bottom: 1px solid var(--border); }
.welcome-home-icon { display: grid; place-items: center; width: 48px; height: 48px; flex-shrink: 0; border-radius: 15px; color: var(--primary); background: var(--primary-soft); }
.welcome-home-icon svg { width: 25px; height: 25px; }
.welcome-small-label { color: var(--text-muted); font-size: 9px; font-weight: 700; letter-spacing: 1.6px; }
.welcome-preview h2 { margin: 2px 0 0; font: 800 23px/1.4 var(--font-heading); letter-spacing: -.8px; }
.welcome-preview-spark { margin-left: auto; color: var(--accent); font-size: 38px; animation: welcome-turn 1.8s ease-out both; }
.welcome-preview-list { padding-block: 8px 18px; }
.welcome-preview-row { display: flex; align-items: center; gap: 12px; padding-block: 16px; font-size: 13px; font-weight: 600; }
.welcome-preview-row + .welcome-preview-row { border-top: 1px dashed var(--border); }
.welcome-preview-row > span:nth-child(2) { flex: 1; }
.welcome-preview-row small { display: block; margin-top: 3px; color: var(--text-muted); font-size: 11px; font-weight: 400; }
.welcome-task-done, .welcome-task-open { display: grid; place-items: center; width: 23px; height: 23px; flex-shrink: 0; border-radius: 8px; border: 1px solid var(--border); }
.welcome-task-done { border-color: var(--success); background: var(--success); color: var(--on-primary); animation: welcome-check .6s 1s both; }
.welcome-task-done svg { width: 16px; height: 16px; }
.welcome-avatar { background: var(--accent-soft); color: var(--text-brand); border-radius: 50%; font-size: 12px; }
.welcome-preview-bottom { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.welcome-preview-bottom > div { min-width: 0; padding: 16px; border-radius: 14px; background: var(--surface-subtle); }
.welcome-preview-bottom > div + div { background: var(--accent-soft); }
.welcome-preview-bottom svg { width: 21px; height: 21px; margin-bottom: 12px; color: var(--success); }
.welcome-preview-bottom > div + div svg { color: var(--warning); }
.welcome-preview-bottom strong, .welcome-preview-bottom span { display: block; }
.welcome-preview-bottom strong { font-size: 12px; }
.welcome-preview-bottom span { font-size: 10px; color: var(--text-muted); margin-top: 4px; }
.welcome-preview figcaption { margin-top: 19px; font-size: 10px; text-align: center; color: var(--text-muted); }
.welcome-section-heading { max-width: 650px; margin-bottom: 36px; }
.welcome-main h2 { font-family: var(--font-heading); }
.welcome-section-heading h2, .welcome-start h2, .welcome-faq h2 { margin: 0; font-size: clamp(1.65rem, 2.7vw, 2.25rem); line-height: 1.25; letter-spacing: -1.2px; }
.welcome-section-heading .welcome-eyebrow, .welcome-start .welcome-eyebrow, .welcome-faq .welcome-eyebrow { margin-bottom: 12px; }
.welcome-features { padding-block: 48px 56px; border-top: 1px solid var(--border); scroll-margin-top: 30px; }
.welcome-feature-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 28px; }
.welcome-feature { min-width: 0; }
.welcome-feature-icon { display: grid; place-items: center; width: 44px; height: 44px; border-radius: 13px; background: var(--primary-soft); color: var(--primary); transition: transform var(--motion-fast); }
.welcome-feature:hover .welcome-feature-icon { transform: translateY(-4px) rotate(-5deg); }
.welcome-feature-icon svg { width: 23px; height: 23px; }
.welcome-feature:nth-child(2) .welcome-feature-icon { background: var(--success-soft); color: var(--success); }
.welcome-feature:nth-child(3) .welcome-feature-icon { background: var(--warning-soft); color: var(--warning); }
.welcome-feature:nth-child(4) .welcome-feature-icon { background: var(--info-soft); color: var(--text); }
.welcome-feature h3 { margin: 18px 0 10px; font: 700 17px/1.4 var(--font-heading); letter-spacing: -.4px; }
.welcome-feature p { margin: 0; color: var(--text-muted); font-size: 13px; line-height: 1.8; }
.welcome-feature-detail { display: block; margin-top: 18px; color: var(--primary); font-size: 10px; font-weight: 600; }
.welcome-together { display: flex; align-items: center; justify-content: center; gap: 12px; margin: 40px 0 0; padding-top: 24px; border-top: 1px solid var(--border); font-size: 12px; color: var(--text-muted); }
.welcome-together svg { width: 20px; height: 20px; flex-shrink: 0; color: var(--primary); }
.welcome-start { display: grid; grid-template-columns: 1fr 1.15fr; gap: 60px; margin-block: 20px 72px; padding: 48px; background: var(--primary-soft); border-radius: var(--radius); }
.welcome-start-heading > .button { margin-top: 25px; }
.welcome-steps { list-style: none; margin: 0; padding: 0; }
.welcome-steps li { display: flex; gap: 20px; }
.welcome-steps li + li { margin-top: 26px; }
.welcome-step-number { padding-top: 2px; font: 700 14px var(--font-heading); color: var(--primary); }
.welcome-steps h3 { margin: 0 0 5px; font-size: 15px; }
.welcome-steps p { margin: 0; font-size: 13px; color: var(--text-muted); }
.welcome-faq { display: grid; grid-template-columns: 1fr 1.15fr; gap: 60px; padding-bottom: 72px; }
.welcome-questions details { border-bottom: 1px solid var(--border); }
.welcome-questions summary { display: flex; align-items: center; justify-content: space-between; gap: 16px; padding: 17px 0; list-style: none; cursor: pointer; font-size: 14px; font-weight: 600; }
.welcome-questions summary::-webkit-details-marker { display: none; }
.welcome-questions summary span { font-size: 23px; font-weight: 400; color: var(--primary); transition: transform var(--motion-fast); }
.welcome-questions [open] summary span { transform: rotate(45deg); }
.welcome-questions details p { margin: 0 0 20px; color: var(--text-muted); font-size: 13px; }
.welcome-footer { display: flex; align-items: center; justify-content: space-between; gap: 24px; border-top: 1px solid var(--border); padding-block: 25px; }
.welcome-footer p { margin: 0; font-size: 11px; color: var(--text-muted); }
.welcome-footer strong { color: var(--primary); font: 800 17px var(--font-heading); margin-right: 14px; }
.welcome-footer .legal-links { margin: 0; font-size: 11px; }
.welcome-feature h3 a { text-decoration: underline; text-underline-offset: .2em; text-decoration-color: var(--border); }
.welcome-feature h3 a:hover { color: var(--primary); text-decoration-color: currentColor; }
.welcome-languages { padding-bottom: 32px; color: var(--text-muted); font-size: var(--font-small); }
.welcome-languages summary { cursor: pointer; padding-block: 12px; }
.welcome-languages ul { display: flex; flex-wrap: wrap; gap: 8px 20px; list-style: none; margin: 12px 0 0; padding: 0; }
.welcome-languages a { display: inline-flex; align-items: center; min-height: 44px; color: var(--text); }
.welcome-languages a:hover, .welcome-languages [aria-current="page"] { color: var(--primary); text-decoration: underline; }
.feature-main { padding-block: 28px 64px; }
.feature-breadcrumb { display: flex; flex-wrap: wrap; gap: 8px; color: var(--text-muted); font-size: var(--font-small); margin-bottom: 48px; }
.feature-breadcrumb a, .feature-related a { color: var(--primary); text-decoration: underline; text-underline-offset: .2em; }
.feature-guide { max-width: 760px; margin-inline: auto; }
.feature-guide h1 { font: 800 clamp(2rem, 4vw, 3.2rem)/1.2 var(--font-heading); letter-spacing: -1px; margin: 0 0 24px; overflow-wrap: break-word; }
.feature-guide .welcome-lead { max-width: none; }
.feature-guide section { margin-top: 48px; }
.feature-guide h2, .feature-related h2 { font-size: clamp(1.35rem, 2.6vw, 1.8rem); line-height: 1.35; }
.feature-guide section p { color: var(--text-muted); }
.feature-related { max-width: 760px; margin: 48px auto 0; padding-top: 24px; border-top: 1px solid var(--border); }
.feature-related li { padding-block: 8px; }
@keyframes welcome-arrive { from { opacity: 0; transform: translateY(16px); } to { opacity: 1; transform: none; } }
@keyframes welcome-settle { from { opacity: 0; transform: translateY(24px) rotate(5deg); } to { opacity: 1; transform: rotate(2deg); } }
@keyframes welcome-turn { from { transform: rotate(-90deg) scale(.6); } to { transform: none; } }
@keyframes welcome-check { from { transform: scale(.6); } 65% { transform: scale(1.15); } to { transform: none; } }
/* Responsive overrides follow their base rules. */
@media (max-width: 1000px) {
    .welcome-header, .welcome-main, .welcome-footer { width: calc(100% - 48px); }
    .welcome-hero { gap: 32px; padding-block: 60px 72px; }
    .welcome-hero h1 { font-size: 2.7rem; letter-spacing: -1.8px; }
    .welcome-preview { padding: 22px; }
    .welcome-feature-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 32px; }
    .welcome-start { padding: 32px; gap: 32px; }
    .welcome-faq { gap: 32px; }
    .welcome-footer p span { display: block; margin-top: 5px; }
}
@media (max-width: 700px) {
    .welcome-header, .welcome-main, .welcome-footer { width: calc(100% - 40px); }
    .welcome-header { padding-block: 14px; }
    .welcome-brand { font-size: 23px; }
    .welcome-brand .site-brand-logo { width: 44px; height: 44px; }
    .welcome-nav { gap: 16px; }
    .welcome-nav-feature { display: none; }
    .welcome-hero { grid-template-columns: 1fr; gap: 40px; padding-block: 42px 52px; }
    .welcome-eyebrow { font-size: 10px; letter-spacing: 1px; }
    .welcome-hero h1 { font-size: clamp(2.15rem, 8.7vw, 3.2rem); letter-spacing: -1.6px; }
    .welcome-lead { font-size: 15px; max-width: none; }
    .welcome-actions { gap: 18px; margin-top: 24px; }
    .welcome-preview { width: min(100% - 12px, 460px); margin-inline: auto; padding: 22px; }
    .welcome-preview h2 { font-size: 21px; }
    .welcome-feature-grid { gap: 32px 20px; }
    .welcome-feature h3 { font-size: 16px; }
    .welcome-feature-detail { font-size: 10px; }
    .welcome-features { padding-top: 36px; padding-bottom: 32px; }
    .welcome-together { align-items: flex-start; text-align: left; }
    .welcome-start { grid-template-columns: 1fr; padding: 28px 24px; margin-bottom: 48px; }
    .welcome-start h2 br { display: none; }
    .welcome-faq { grid-template-columns: 1fr; gap: 22px; padding-bottom: 48px; }
    .welcome-footer { flex-direction: column; align-items: flex-start; gap: 20px; }
    .welcome-footer .legal-links { justify-content: flex-start; gap: 16px; }
    .feature-guide h1 { font-size: clamp(1.65rem, 7.8vw, 2rem); hyphens: auto; }
}
@media (max-width: 380px) {
    .welcome-brand { font-size: 21px; }
    .welcome-brand .site-brand-logo { width: 40px; height: 40px; }
    .welcome-feature-grid { grid-template-columns: 1fr; }
    .welcome-preview { padding: 18px; }
    .welcome-preview-top { gap: 10px; }
    .welcome-preview-spark { font-size: 28px; }
    .welcome-preview-bottom > div { padding: 12px; }
}
@media (prefers-reduced-motion: reduce) {
    .welcome-body *, .welcome-body *::before, .welcome-body *::after { animation: none !important; transition: none !important; }
}

.welcome-body:lang(zh) h1, .welcome-body:lang(ja) h1,
.welcome-body:lang(zh) h2, .welcome-body:lang(ja) h2,
.welcome-body:lang(zh) h3, .welcome-body:lang(ja) h3,
.welcome-body:lang(zh) .welcome-eyebrow, .welcome-body:lang(ja) .welcome-eyebrow,
.welcome-body:lang(zh) .welcome-small-label, .welcome-body:lang(ja) .welcome-small-label { letter-spacing: normal; }