:root{color-scheme:light;--accent: #de2910;--accent-strong: #b81f0b;--accent-soft: #fdeeeb;--accent-ring: rgba(222, 41, 16, .16);--tone-1: #d92b1c;--tone-2: #c9880a;--tone-3: #2563d9;--tone-4: #0d6e8c;--verdict-correct: #1f8a5b;--verdict-wrong: #c9880a;--bg: #faf7f5;--bg-glow: radial-gradient(60rem 32rem at 78% -8%, rgba(222, 41, 16, .08), transparent 60%);--surface: #ffffff;--surface-muted: #fdf9f7;--border: #efe5e1;--border-strong: #e3d6d1;--text: #1c1512;--text-secondary: #574a46;--text-muted: #8d7d78;--shadow-sm: 0 1px 2px rgba(60, 24, 16, .05);--shadow-md: 0 6px 20px -8px rgba(60, 24, 16, .16), 0 1px 2px rgba(60, 24, 16, .05);--shadow-lg: 0 18px 48px -20px rgba(60, 24, 16, .3), 0 2px 6px rgba(60, 24, 16, .06);--shadow-accent: 0 14px 32px -14px rgba(222, 41, 16, .45);--nav-bg: rgba(255, 255, 255, .82);--radius-sm: 10px;--radius-md: 14px;--radius-lg: 20px;--radius-pill: 999px;--shell: 1120px;--nav-height: 68px;--ease: cubic-bezier(.32, .72, .3, 1);--speed: .18s}:root[data-theme=dark]{color-scheme:dark;--accent: #ff6b52;--accent-strong: #ff8570;--accent-soft: rgba(255, 107, 82, .14);--accent-ring: rgba(255, 107, 82, .24);--tone-1: #ff6b52;--tone-2: #f5b83d;--tone-3: #6fa2ff;--tone-4: #45c7dd;--verdict-correct: #46c48b;--verdict-wrong: #f5b83d;--bg: #16110f;--bg-glow: radial-gradient(60rem 32rem at 78% -8%, rgba(255, 107, 82, .11), transparent 60%);--surface: #1f1815;--surface-muted: #261e1a;--border: #362b27;--border-strong: #453832;--text: #f6f0ed;--text-secondary: #d3c7c2;--text-muted: #9b8d87;--shadow-sm: 0 1px 2px rgba(0, 0, 0, .32);--shadow-md: 0 8px 24px -12px rgba(0, 0, 0, .62), 0 1px 2px rgba(0, 0, 0, .36);--shadow-lg: 0 24px 56px -24px rgba(0, 0, 0, .76), 0 2px 8px rgba(0, 0, 0, .42);--shadow-accent: 0 16px 36px -18px rgba(255, 107, 82, .5);--nav-bg: rgba(22, 17, 15, .8)}*,*:before,*:after{box-sizing:border-box}html{-webkit-text-size-adjust:100%}body{margin:0;min-height:100vh;background-color:var(--bg);background-image:var(--bg-glow);background-repeat:no-repeat;color:var(--text);font-family:Inter,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica Neue,Arial,sans-serif;font-size:16px;line-height:1.6;-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility;transition:background-color var(--speed) var(--ease),color var(--speed) var(--ease)}body.is-locked{overflow:hidden}h1,h2,h3,p{margin:0}h1,h2,h3{letter-spacing:-.02em;line-height:1.15}a{color:inherit;text-decoration:none}button{font:inherit;color:inherit}ul{margin:0;padding:0;list-style:none}svg{display:block}:focus-visible{outline:2px solid var(--accent);outline-offset:3px;border-radius:6px}.shell{width:100%;max-width:var(--shell);margin-inline:auto;padding-inline:24px}.visually-hidden{position:absolute;width:1px;height:1px;margin:-1px;padding:0;overflow:hidden;clip-path:inset(50%);white-space:nowrap;border:0}.skip-link{position:absolute;left:16px;top:-90px;z-index:200;padding:10px 16px;border-radius:var(--radius-sm);background:var(--surface);box-shadow:var(--shadow-md);transition:top var(--speed) var(--ease)}.skip-link:focus-visible{top:14px}.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;padding:0 20px;height:44px;border:1px solid transparent;border-radius:var(--radius-sm);font-size:.9375rem;font-weight:600;cursor:pointer;white-space:nowrap;transition:transform var(--speed) var(--ease),background-color var(--speed) var(--ease),border-color var(--speed) var(--ease),box-shadow var(--speed) var(--ease),color var(--speed) var(--ease)}.btn:hover{transform:translateY(-1px)}.btn:active{transform:translateY(0)}.btn--primary{background:var(--accent);border-color:var(--accent);color:#fff;box-shadow:var(--shadow-accent)}:root[data-theme=dark] .btn--primary{color:#24140f}.btn--primary:hover{background:var(--accent-strong);border-color:var(--accent-strong)}.btn--secondary{background:var(--surface);border-color:var(--border-strong);color:var(--text);box-shadow:var(--shadow-sm)}.btn--secondary:hover{border-color:var(--accent);color:var(--accent)}.btn--ghost{background:transparent;border-color:var(--border-strong);color:var(--text-secondary)}.btn--ghost:hover{border-color:var(--accent);color:var(--accent)}.icon-btn{display:inline-flex;align-items:center;justify-content:center;width:38px;height:38px;border:1px solid transparent;border-radius:var(--radius-sm);background:transparent;color:var(--text-secondary);cursor:pointer;transition:background-color var(--speed) var(--ease),color var(--speed) var(--ease),border-color var(--speed) var(--ease)}.icon-btn:hover{background:var(--accent-soft);color:var(--accent)}.section-head{margin-bottom:28px}.section-head__row{display:flex;align-items:center;gap:11px;padding-bottom:14px;border-bottom:1px solid var(--border)}.section-head__mark{flex:none;color:var(--accent)}.section-head__title{font-size:clamp(1.25rem,1.05rem + .8vw,1.625rem);font-weight:700;letter-spacing:-.01em}.section-head__intro{display:flex;flex-direction:column;gap:12px;margin-top:16px;color:var(--text-muted);font-size:.9375rem;line-height:1.65}@media (prefers-reduced-motion: reduce){*,*:before,*:after{animation-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important;scroll-behavior:auto!important}}.tone-contour{overflow:visible;transition:color var(--speed) var(--ease)}.tone-contour--1{color:var(--tone-1)}.tone-contour--2{color:var(--tone-2)}.tone-contour--3{color:var(--tone-3)}.tone-contour--4{color:var(--tone-4)}.dual-tone-contour{display:inline-flex;align-items:center;gap:10px}.dual-tone-contour__join{width:3px;height:3px;border-radius:50%;background:var(--border-strong)}.mobile-nav{position:fixed;top:0;right:0;bottom:0;left:0;z-index:150;pointer-events:none}.mobile-nav__scrim{position:absolute;top:0;right:0;bottom:0;left:0;background:#1c0e0a6b;opacity:0;transition:opacity var(--speed) var(--ease)}.mobile-nav__panel{position:absolute;inset:0 0 0 auto;display:flex;flex-direction:column;width:min(360px,88vw);padding:18px 20px 22px;overflow-y:auto;background:var(--surface);border-left:1px solid var(--border);box-shadow:var(--shadow-lg);transform:translate(100%);transition:transform .22s var(--ease)}.mobile-nav.is-open{pointer-events:auto}.mobile-nav.is-open .mobile-nav__scrim{opacity:1}.mobile-nav.is-open .mobile-nav__panel{transform:translate(0)}.mobile-nav__head{display:flex;align-items:center;justify-content:space-between;margin-bottom:22px}.mobile-nav__section-label{margin-bottom:8px;color:var(--text-muted);font-size:.6875rem;font-weight:600;letter-spacing:.09em;text-transform:uppercase}.mobile-nav__accordion>li+li{border-top:1px solid var(--border)}.mobile-nav__accordion-trigger{display:flex;align-items:center;justify-content:space-between;width:100%;padding:13px 4px;border:0;background:transparent;font-size:.9375rem;font-weight:600;cursor:pointer;transition:color var(--speed) var(--ease)}.mobile-nav__accordion-trigger:hover,.mobile-nav__accordion-trigger.is-open{color:var(--accent)}.mobile-nav__chevron{color:var(--text-muted);transition:transform var(--speed) var(--ease)}.mobile-nav__accordion-trigger.is-open .mobile-nav__chevron{transform:rotate(180deg);color:var(--accent)}.mobile-nav__panel-body{padding-bottom:10px}.mobile-nav__dual-tone{display:flex;align-items:center;justify-content:space-between;padding:9px 12px;border-radius:8px;color:var(--text-secondary);font-size:.875rem;transition:background-color var(--speed) var(--ease),color var(--speed) var(--ease)}.mobile-nav__dual-tone:hover{background:var(--accent-soft);color:var(--accent)}.mobile-nav__dual-tone-contour{display:inline-flex;gap:5px}.mobile-nav__links{margin-top:18px;padding-top:14px;border-top:1px solid var(--border)}.mobile-nav__links:first-child{margin-top:0;margin-bottom:18px;padding-top:0;padding-bottom:14px;border-top:0;border-bottom:1px solid var(--border)}.mobile-nav__link{display:block;padding:11px 4px;font-size:.9375rem;font-weight:600;color:var(--text-secondary);transition:color var(--speed) var(--ease)}.mobile-nav__link:hover,.mobile-nav__link.is-active{color:var(--accent)}.mobile-nav__foot{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-top:auto;padding-top:24px}@media (min-width: 941px){.mobile-nav{display:none}}.nav{position:sticky;top:0;z-index:100;background:var(--nav-bg);-webkit-backdrop-filter:saturate(180%) blur(14px);backdrop-filter:saturate(180%) blur(14px);border-bottom:1px solid var(--border);transition:background-color var(--speed) var(--ease),border-color var(--speed) var(--ease)}.nav__inner{display:flex;align-items:center;gap:20px;height:var(--nav-height)}.nav__brand{display:inline-flex;align-items:center;gap:9px;flex:none}.nav__brand-mark{display:grid;place-items:center;color:var(--accent)}.nav__brand-name{font-size:1.0625rem;font-weight:700;letter-spacing:-.02em}.nav__links{margin-left:auto}.nav__list{display:flex;align-items:center;gap:2px}.nav__item{position:relative}.nav__link,.nav__trigger{display:inline-flex;align-items:center;gap:5px;height:36px;padding:0 12px;border:0;border-radius:var(--radius-sm);background:transparent;color:var(--text-secondary);font-size:.875rem;font-weight:500;cursor:pointer;transition:color var(--speed) var(--ease),background-color var(--speed) var(--ease)}.nav__link:hover,.nav__trigger:hover,.nav__trigger.is-open{color:var(--accent);background:var(--accent-soft)}.nav__link.is-active{color:var(--text);font-weight:600}.nav__chevron{opacity:.6;transition:transform var(--speed) var(--ease)}.nav__trigger.is-open .nav__chevron{transform:rotate(180deg)}.dropdown{position:absolute;top:calc(100% + 8px);left:0;min-width:168px;padding:6px;border:1px solid var(--border);border-radius:var(--radius-md);background:var(--surface);box-shadow:var(--shadow-lg);opacity:0;visibility:hidden;pointer-events:none;transform:translateY(-4px);transition:opacity var(--speed) var(--ease),transform var(--speed) var(--ease),visibility 0s linear var(--speed)}.dropdown.is-open{opacity:1;visibility:visible;pointer-events:auto;transform:translateY(0);transition:opacity var(--speed) var(--ease),transform var(--speed) var(--ease),visibility 0s}.dropdown:before{content:"";position:absolute;top:-10px;right:0;bottom:100%;left:0}.dropdown__item{display:flex;align-items:center;justify-content:space-between;gap:14px;padding:8px 10px;border-radius:8px;color:var(--text-secondary);font-size:.875rem;font-weight:500;transition:background-color var(--speed) var(--ease),color var(--speed) var(--ease)}.dropdown__item:hover,.dropdown__item:focus-visible{background:var(--accent-soft);color:var(--accent)}.dropdown__contour{display:inline-flex;align-items:center;gap:5px;opacity:.85}.nav__actions{display:flex;align-items:center;gap:2px;flex:none;margin-left:8px}.nav .nav__burger{display:none}@media (max-width: 940px){.nav__links,.nav__action{display:none}.nav__actions{margin-left:auto}.nav .nav__burger{display:inline-flex}}.footer{border-top:1px solid var(--border);background:var(--surface-muted)}.footer__inner{display:flex;align-items:center;gap:24px;flex-wrap:wrap;padding-block:28px}.footer__links{display:flex;gap:22px}.footer__links a{color:var(--text-muted);font-size:.875rem;transition:color var(--speed) var(--ease)}.footer__links a:hover{color:var(--accent)}.footer__note{margin-left:auto;color:var(--text-muted);font-size:.8125rem}@media (max-width: 640px){.footer__note{margin-left:0;width:100%}}.ad-slot{width:100%;height:100%}.ad-slot__unit{display:block;width:100%;height:100%}.ad-slot__unit[data-ad-status=unfilled]{display:none}.ad-slot--preview{display:grid;place-items:center;border:1px dashed var(--border-strong);border-radius:var(--radius-sm);background-color:var(--surface-muted);background-image:repeating-linear-gradient(135deg,transparent 0 8px,var(--border) 8px 9px);color:var(--text-muted)}.ad-slot__preview-label{padding:3px 8px;border-radius:var(--radius-pill);background:var(--surface);font-size:.6875rem;font-weight:600;letter-spacing:.08em;text-transform:uppercase}.ad-rail{display:none}@media (min-width: 1440px) and (min-height: 800px){.nav,main,.footer,.ad-banner{padding-right:348px}.ad-rail{position:fixed;top:calc(var(--nav-height) + 28px);bottom:124px;right:24px;z-index:90;display:flex;align-items:flex-start;width:300px;overflow:hidden}.ad-rail .ad-slot{height:600px}}.ad-banner{position:fixed;right:0;bottom:0;left:0;z-index:120;display:flex;align-items:center;justify-content:center;gap:10px;padding:8px 12px;background:var(--nav-bg);-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);border-top:1px solid var(--border)}.ad-banner .ad-slot{width:320px;height:50px}.ad-banner__close{display:grid;place-items:center;flex:none;width:26px;height:26px;padding:0;border:1px solid var(--border);border-radius:var(--radius-pill);background:var(--surface);color:var(--text-muted);cursor:pointer;transition:color var(--speed) var(--ease),border-color var(--speed) var(--ease)}.ad-banner__close:hover{color:var(--text);border-color:var(--border-strong)}body.has-ad-banner{padding-bottom:68px}@media (min-width: 768px){.ad-banner .ad-slot{width:728px;height:90px}body.has-ad-banner{padding-bottom:108px}}.hero{position:relative;overflow:hidden;padding:clamp(48px,6vw,84px) 0 clamp(28px,4vw,52px)}.hero__inner{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,.85fr);align-items:center;gap:48px}.hero__eyebrow{margin-bottom:18px;color:var(--accent);font-size:.75rem;font-weight:600;letter-spacing:.12em;text-transform:uppercase}.hero__title{max-width:12ch;font-size:clamp(2.25rem,1.4rem + 3.2vw,3.4rem);font-weight:700;letter-spacing:-.035em;line-height:1.08}.hero__accent{color:var(--accent)}.hero__lead{max-width:46ch;margin-top:20px;color:var(--text-muted);font-size:1rem}.hero__actions{display:flex;flex-wrap:wrap;gap:12px;margin-top:30px}.hero__visual{position:relative;height:344px;display:grid;place-items:center}.hero__rings{position:absolute;width:118%;max-width:460px;fill:none;stroke:var(--accent);stroke-width:1;opacity:.13}.hero__dot{position:absolute;border-radius:50%;background:var(--accent);opacity:.4;animation:hero-float 7s var(--ease) infinite}.hero__dot--a{width:9px;height:9px;top:12%;right:20%}.hero__dot--b{width:6px;height:6px;top:34%;left:6%;opacity:.28;animation-delay:-1.4s}.hero__dot--c{width:12px;height:12px;bottom:20%;left:22%;opacity:.22;animation-delay:-3s}.hero__dot--d{width:7px;height:7px;bottom:8%;right:12%;opacity:.32;animation-delay:-4.6s}@keyframes hero-float{0%,to{transform:translateY(0)}50%{transform:translateY(-11px)}}.syllable-card{position:absolute;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:10px;width:148px;height:158px;border:1px solid var(--border);border-radius:var(--radius-lg);background:var(--surface);box-shadow:var(--shadow-lg);animation:hero-float 8s var(--ease) infinite}.syllable-card--first{top:16%;left:10%;transform:rotate(-7deg)}.syllable-card--second{right:6%;bottom:14%;transform:rotate(6deg);animation-delay:-2.6s}.syllable-card__pinyin{color:var(--accent);font-size:2rem;font-weight:600;letter-spacing:-.01em;line-height:1}.syllable-card__wave{color:var(--accent);opacity:.35}@media (max-width: 940px){.hero__inner{grid-template-columns:1fr;gap:8px}.hero__title,.hero__lead{max-width:none}.hero__visual{height:244px;margin-top:8px}.hero__rings{max-width:360px}.syllable-card{width:124px;height:132px}.syllable-card--first{left:16%}.syllable-card--second{right:16%}}@media (max-width: 560px){.hero__actions .btn{flex:1 1 160px}.hero__visual{height:220px}.hero__rings{max-width:320px}.syllable-card{width:106px;height:116px}.syllable-card__pinyin{font-size:1.625rem}}.audio-player{display:flex;flex-direction:column;align-items:center;gap:10px}.audio-player:has(.is-labelled){gap:4px}.audio-player__controls{display:flex;align-items:center;gap:12px}.audio-player__play{position:relative;display:grid;place-items:center;border:1px solid var(--accent);border-radius:50%;background:var(--accent);color:#fff;cursor:pointer;box-shadow:var(--shadow-accent);transition:transform var(--speed) var(--ease),background-color var(--speed) var(--ease),box-shadow var(--speed) var(--ease)}:root[data-theme=dark] .audio-player__play{color:#24140f}.audio-player--lg .audio-player__play{width:84px;height:84px}.audio-player--md .audio-player__play{width:46px;height:46px}.audio-player__play:hover:not(:disabled){transform:translateY(-2px);background:var(--accent-strong)}.audio-player__play:active:not(:disabled){transform:translateY(0)}.audio-player__play:disabled{background:var(--surface-muted);border-color:var(--border-strong);color:var(--text-muted);box-shadow:none;cursor:not-allowed}.audio-player__play.is-active{background:var(--accent-strong)}.audio-player__play.is-active:after{content:"";position:absolute;top:-6px;right:-6px;bottom:-6px;left:-6px;border:2px solid var(--accent);border-radius:50%;opacity:0;animation:audio-pulse 1.6s var(--ease) infinite}@keyframes audio-pulse{0%{transform:scale(.94);opacity:.55}to{transform:scale(1.22);opacity:0}}.audio-player__icon{display:grid;place-items:center;padding-left:2px}.audio-player__play.is-active .audio-player__icon,.audio-player__play.is-labelled .audio-player__icon{padding-left:0}.audio-player__play.is-labelled,.audio-player__play.is-labelled:after{border-radius:var(--radius-md)}.audio-player__play.is-labelled{display:inline-flex;width:auto;font-weight:600;letter-spacing:.01em}.audio-player--lg .audio-player__play.is-labelled{gap:10px;min-width:168px;height:52px;padding:0 26px;font-size:1rem}.audio-player--md .audio-player__play.is-labelled{gap:7px;min-width:116px;height:38px;padding:0 18px;font-size:.875rem}.audio-player__spinner{animation:audio-spin .8s linear infinite}@keyframes audio-spin{to{transform:rotate(360deg)}}.audio-player__replay{display:inline-flex;align-items:center;gap:7px;padding:0 14px;height:38px;border:1px solid var(--border-strong);border-radius:var(--radius-pill);background:var(--surface);color:var(--text-secondary);font-size:.8125rem;font-weight:600;cursor:pointer;transition:border-color var(--speed) var(--ease),color var(--speed) var(--ease)}.audio-player__replay:hover:not(:disabled){border-color:var(--accent);color:var(--accent)}.audio-player__replay:disabled{opacity:.5;cursor:not-allowed}.audio-player__status{min-height:18px;color:var(--text-muted);font-size:.8125rem;text-align:center}.audio-player__error{display:inline-flex;align-items:center;gap:6px;color:var(--tone-2)}.audio-player__unavailable{color:var(--text-muted)}.why-tones{padding:clamp(24px,3vw,40px) 0 clamp(36px,4.5vw,56px);background:var(--surface-muted)}.why-tones__pairs{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px}.why-tones__pair{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));border:1px solid var(--border);border-radius:var(--radius-md);background:var(--surface);box-shadow:var(--shadow-sm);overflow:hidden}.why-tones__word{display:flex;flex-direction:column;align-items:center;gap:6px;padding:26px 18px 22px;text-align:center}.why-tones__word+.why-tones__word{border-left:1px solid var(--border)}.why-tones__characters{margin-top:10px;font-size:clamp(1.75rem,1.4rem + 1.4vw,2.25rem);font-weight:600;letter-spacing:.05em}.why-tones__pinyin{color:var(--accent);font-size:1rem;font-weight:600}.why-tones__meaning{color:var(--text-secondary);font-size:.875rem}.why-tones__tone{margin-bottom:12px;color:var(--text-muted);font-size:.75rem;font-weight:600;letter-spacing:.06em;text-transform:uppercase}@media (max-width: 940px){.why-tones__pairs{grid-template-columns:minmax(0,1fr)}}@media (max-width: 420px){.why-tones__word{padding:20px 12px 18px}}.four-tones{padding:clamp(28px,3.5vw,44px) 0 clamp(36px,4.5vw,56px)}.tone-cards{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:16px}.tone-cards__item{display:flex;flex-direction:column;align-items:center;gap:6px;padding:24px 18px 22px;border:1px solid var(--border);border-radius:var(--radius-md);background:var(--surface);box-shadow:var(--shadow-sm);text-align:center}.tone-cards__label{margin-top:4px;color:var(--text-muted);font-size:.75rem;font-weight:600;letter-spacing:.06em;text-transform:uppercase}.tone-cards__characters{font-size:clamp(1.75rem,1.4rem + 1.4vw,2.25rem);font-weight:600;letter-spacing:.05em}.tone-cards__pinyin{color:var(--accent);font-size:1rem;font-weight:600}.tone-cards__meaning{color:var(--text-secondary);font-size:.875rem}.tone-cards__description{margin-bottom:12px;color:var(--text-muted);font-size:.8125rem;line-height:1.5}@media (max-width: 940px){.tone-cards{grid-template-columns:repeat(2,minmax(0,1fr))}}@media (max-width: 520px){.tone-cards{grid-template-columns:minmax(0,1fr)}}.prose-section{padding:clamp(28px,3.5vw,44px) 0 clamp(36px,4.5vw,56px)}.prose-section.is-muted{background:var(--surface-muted)}.prose-section__body{display:flex;flex-direction:column;gap:14px;color:var(--text-muted);font-size:.9375rem;line-height:1.65}.prose-section__body ul{display:flex;flex-direction:column;gap:10px;margin:0;padding-left:20px;list-style:disc}.prose-section__body strong{color:var(--text)}.tone-grid-section{padding:clamp(28px,3.5vw,44px) 0 clamp(48px,6vw,76px)}.tone-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:16px}.tone-card{display:flex}.tone-card__link{display:flex;flex-direction:column;align-items:center;gap:6px;width:100%;padding:26px 18px 22px;border:1px solid var(--border);border-radius:var(--radius-md);background:var(--surface);box-shadow:var(--shadow-sm);text-align:center;cursor:pointer;transition:transform var(--speed) var(--ease),border-color var(--speed) var(--ease),box-shadow var(--speed) var(--ease)}.tone-card__link:hover,.tone-card__link:focus-visible{transform:translateY(-3px);border-color:var(--accent);box-shadow:var(--shadow-md),0 0 0 4px var(--accent-ring)}.tone-card__visual{display:grid;place-items:center;height:42px;margin-bottom:8px}.tone-card__label{font-size:1rem;font-weight:700;letter-spacing:-.01em}@media (max-width: 940px){.tone-grid{grid-template-columns:repeat(2,minmax(0,1fr))}}@media (max-width: 520px){.tone-grid{grid-template-columns:minmax(0,1fr);gap:12px}.tone-card__link{flex-direction:row;align-items:center;gap:18px;padding:16px 20px;text-align:left}.tone-card__visual{height:auto;margin-bottom:0}}.flashcard{display:flex;flex-direction:column;align-items:center;gap:22px;width:100%;max-width:520px;padding:clamp(28px,4vw,40px) clamp(22px,4vw,40px);border:1px solid 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