:root{color-scheme:light;--paper:#f5f0e6;--surface:#fffcf5;--surface-warm:#faf5ea;--ink:#20251f;--muted:#667069;--border:#d8d0c3;--border-dark:#bdb4a6;--cinnabar:#a63d32;--cinnabar-dark:#843027;--cinnabar-soft:#f4e1dc;--jade:#2f6656;--jade-soft:#dfece5;--amber:#8b5e1a;--amber-soft:#f4e8ce;--proper-name:#75428f;--proper-name-soft:#eee3f4;--focus:#1d4ed8;--shadow:0 24px 70px #40322014, 0 3px 12px #4032200d;--font-ui:ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;--font-hanzi:"Songti SC", "STSong", "Noto Serif CJK SC", serif}*{box-sizing:border-box}html{background:var(--paper);min-width:320px}body{min-width:320px;min-height:100vh;color:var(--ink);background:radial-gradient(circle at 14% 8%, #a63d320e, transparent 24rem), radial-gradient(circle at 85% 32%, #2f66560d, transparent 28rem), linear-gradient(#5a4b3705 1px, transparent 1px), var(--paper);font-family:var(--font-ui);text-rendering:optimizelegibility;-webkit-font-smoothing:antialiased;background-size:auto,auto,100% 32px,auto;margin:0;line-height:1.5}button,input,select{color:inherit;font:inherit}button,select{cursor:pointer}button:focus-visible,input:focus-visible,select:focus-visible,[tabindex="-1"]:focus-visible{outline:3px solid var(--focus);outline-offset:3px}a{color:inherit}.sr-only{clip:rect(0, 0, 0, 0);white-space:nowrap;border:0;width:1px;height:1px;margin:-1px;padding:0;position:absolute;overflow:hidden}.app-shell{width:min(1120px,100% - 40px);margin:0 auto;padding:28px 0 72px}.site-header{justify-content:space-between;align-items:center;gap:24px;min-height:64px;display:flex}.brand{align-items:center;gap:12px;text-decoration:none;display:inline-flex}.brand-mark{flex:none;width:48px;height:48px;display:block}.brand strong,.brand small{display:block}.brand strong{letter-spacing:-.015em;font-size:1.05rem}.brand small{color:var(--muted);margin-top:1px;font-size:.76rem}.account-area{justify-content:flex-end;align-items:center;gap:10px;display:flex;position:relative}.sync-label{color:var(--muted);text-align:right;font-size:.78rem}.sync-label:before{background:var(--border-dark);content:"";vertical-align:1px;border-radius:50%;width:7px;height:7px;margin-right:7px;display:inline-block}.sync-synced:before{background:var(--jade)}.sync-syncing:before{background:var(--amber);animation:1.4s ease-in-out infinite pulse}.sync-error:before,.sync-offline:before{background:var(--cinnabar)}.avatar-button{border:1px solid var(--ink);background:var(--surface);border-radius:50%;place-items:center;width:44px;height:44px;padding:0;font-size:.82rem;font-weight:800;display:grid}.account-menu-wrap{position:relative}.account-menu{z-index:30;border:1px solid var(--border);background:var(--surface);width:min(280px,100vw - 32px);box-shadow:var(--shadow);border-radius:14px;gap:3px;padding:16px;display:grid;position:absolute;top:calc(100% + 10px);right:0}.account-menu span{color:var(--muted);text-overflow:ellipsis;font-size:.83rem;overflow:hidden}.account-menu button{border:0;border-top:1px solid var(--border);min-height:44px;color:var(--cinnabar);text-align:left;background:0 0;margin-top:10px;font-weight:700}.view-tabs{border-bottom:1px solid var(--border);grid-template-columns:repeat(4,minmax(0,1fr));margin-top:26px;display:grid}.view-tabs button{min-height:54px;color:var(--muted);background:0 0;border:0;justify-content:center;align-items:center;gap:9px;font-weight:700;display:flex;position:relative}.view-tabs button:after{content:"";background:0 0;border-radius:3px 3px 0 0;height:3px;position:absolute;bottom:-1px;left:14%;right:14%}.view-tabs button:hover{color:var(--ink)}.view-tabs button.is-active{color:var(--cinnabar)}.view-tabs button.is-active:after{background:var(--cinnabar)}.count-pill{min-width:28px;color:inherit;font-variant-numeric:tabular-nums;background:#6670691a;border-radius:999px;padding:2px 8px;font-size:.75rem}.view-tabs .is-active .count-pill{background:var(--cinnabar-soft)}.guest-note,.inline-alert{border:1px solid var(--border);color:var(--muted);background:#fffcf5b3;border-radius:14px;align-items:center;gap:12px;margin-top:18px;padding:12px 16px;font-size:.86rem;display:flex}.guest-note p{flex:1;margin:0}.guest-note{border-style:dashed;margin-top:10px}.inline-alert{background:var(--amber-soft);color:#64420f;border-color:#d7b275}.text-button{min-height:44px;color:var(--cinnabar);text-underline-offset:3px;background:0 0;border:0;padding:5px 8px;font-size:.84rem;font-weight:800;text-decoration:underline #0000}.text-button:hover{text-decoration-color:currentColor}.align-left{justify-self:start;padding-left:0}.search-row{align-items:center;gap:12px;margin:26px 0 24px;display:flex}.search-field{flex:1;align-items:center;min-width:0;display:flex;position:relative}.search-field input{border:1px solid var(--border);background:#fffcf5e6;border-radius:14px;width:100%;height:50px;padding:0 48px 0 45px;box-shadow:inset 0 1px #fffc}.search-field input::placeholder{color:#7b817c}.search-field input:focus{border-color:var(--ink);background:var(--surface)}.search-icon{z-index:1;color:var(--muted);font-size:1.45rem;line-height:1;position:absolute;left:16px;transform:rotate(-15deg)}.search-field button{width:44px;height:44px;color:var(--muted);background:0 0;border:0;font-size:1.3rem;position:absolute;right:3px}.button{border:1px solid var(--border-dark);background:var(--surface);border-radius:12px;justify-content:center;align-items:center;gap:10px;min-height:48px;padding:11px 18px;font-weight:800;line-height:1.2;transition:transform .15s,background-color .15s,box-shadow .15s;display:inline-flex}.button:hover{transform:translateY(-1px);box-shadow:0 7px 20px #3a2d1f17}.button:active{transform:translateY(0)}.button:disabled{cursor:wait;opacity:.62;box-shadow:none;transform:none}.button-small{min-height:42px;padding:8px 14px;font-size:.83rem}.button-primary{border-color:var(--cinnabar);background:var(--cinnabar);color:#fffdf8}.button-primary:hover{border-color:var(--cinnabar-dark);background:var(--cinnabar-dark)}.button-secondary{border-color:var(--jade);background:var(--surface);color:var(--jade)}.button-secondary:hover{background:var(--jade-soft)}.button-ink{border-color:var(--ink);color:var(--ink)}.filter-trigger{min-width:110px;display:none}.study-layout{grid-template-columns:224px minmax(0,720px);justify-content:center;align-items:start;gap:32px;display:grid}.filter-panel{border:1px solid var(--border);background:#fffcf5b8;border-radius:18px;gap:18px;padding:22px;display:grid;position:sticky;top:24px}.panel-heading{border-bottom:1px solid var(--border);padding-bottom:15px}.panel-heading p{margin:0}.panel-heading p:last-child{margin-top:2px;font-size:1.05rem;font-weight:800}.filter-panel label,.sheet label{color:var(--muted);gap:7px;font-size:.78rem;font-weight:800;display:grid}select{border:1px solid var(--border);background:var(--surface);width:100%;min-height:44px;color:var(--ink);border-radius:10px;padding:8px 34px 8px 11px}.direction-legend{border-top:1px solid var(--border);grid-template-columns:repeat(2,1fr);gap:6px;margin-top:3px;padding-top:18px;display:grid}.direction-legend span{background:var(--surface-warm);color:var(--cinnabar);text-align:center;border-radius:7px;padding:5px 4px;font-size:.67rem;font-weight:900}.direction-legend .how-it-works{grid-column:1/-1;justify-self:center;margin-top:3px;padding-left:4px;padding-right:4px}.session-panel{min-width:0}.session-progress{margin-bottom:13px}.session-progress>div:first-child{color:var(--muted);justify-content:space-between;align-items:center;gap:12px;margin-bottom:9px;font-size:.78rem;font-weight:750;display:flex}.direction-badge{background:var(--cinnabar-soft);color:var(--cinnabar-dark);border-radius:999px;padding:4px 9px;font-size:.7rem}.progress-track{background:#ded6c9;border-radius:999px;height:5px;overflow:hidden}.progress-track span{border-radius:inherit;background:var(--cinnabar);height:100%;transition:width .18s;display:block}.study-card{border:1px solid var(--border);background:var(--surface);min-height:400px;box-shadow:var(--shadow);border-radius:24px;position:relative;overflow:hidden}.study-card:before{content:"";background:#a63d3224;width:1px;position:absolute;top:0;bottom:0;left:31px}.study-card:after{background:var(--cinnabar);content:"";border-radius:50%;width:7px;height:7px;position:absolute;top:18px;right:70px;box-shadow:0 15px #a63d3233,0 30px #a63d3217}.card-prompt{text-align:center;place-content:center;min-height:398px;padding:46px 56px 54px 68px;display:grid}.eyebrow{color:var(--cinnabar);letter-spacing:.14em;text-transform:uppercase;margin:0;font-size:.68rem;font-weight:900}.card-prompt .eyebrow{margin-bottom:26px}.card-prompt h2{text-wrap:balance;max-width:15ch;margin:0}.prompt-hanzi,.answer-hanzi{font-family:var(--font-hanzi);font-weight:600;line-height:1.16}.prompt-hanzi{font-size:clamp(2.75rem,8vw,5.5rem)}.prompt-spanish{letter-spacing:-.035em;font-size:clamp(1.75rem,4vw,3.25rem);font-weight:720;line-height:1.16}.card-answer{border-top:1px solid var(--border);background:linear-gradient(90deg, transparent 0, transparent 31px, #a63d3214 31px, #a63d3214 32px, transparent 32px), var(--surface-warm);padding:42px 56px 48px 68px;animation:.17s ease-out both reveal;position:relative}.card-answer:before{background:var(--paper);width:42px;height:11px;box-shadow:0 1px 0 var(--border);content:"";border-radius:50%;position:absolute;top:-6px;left:50%;transform:translate(-50%)}.favorite-button{z-index:2;border:1px solid var(--border);background:color-mix(in srgb, var(--surface) 88%, transparent);width:40px;height:40px;color:var(--muted);border-radius:50%;place-items:center;padding:0;font-size:1.4rem;line-height:1;display:grid;position:absolute;top:16px;right:18px;box-shadow:0 3px 10px #30281e14}.favorite-button:hover{border-color:var(--cinnabar);color:var(--cinnabar)}.favorite-button.is-favorite{border-color:var(--cinnabar);background:var(--cinnabar-soft);color:var(--cinnabar)}.answer-spanish,.answer-hanzi{color:var(--ink);margin:10px 0 28px}.answer-spanish{letter-spacing:-.03em;font-size:clamp(1.65rem,4vw,2.65rem);font-weight:750;line-height:1.18}.answer-hanzi{font-size:clamp(2.5rem,7vw,4.5rem)}.answer-details{gap:20px;margin:0;display:grid}.answer-details>div{grid-template-columns:105px 1fr;gap:18px;display:grid}.answer-details dt,.example-block h3{color:var(--muted);letter-spacing:.06em;text-transform:uppercase;font-size:.73rem;font-weight:900}.answer-details dd{margin:0}.answer-details>div:first-child dd{color:var(--cinnabar-dark);font-size:1.08rem;font-weight:750}.example-block{border-left:3px solid var(--jade);background:var(--jade-soft);border-radius:0 12px 12px 0;margin-top:28px;padding:22px 24px}.example-block h3{color:var(--jade);margin:0 0 12px}.example-block p{margin:4px 0}.example-block .example-hanzi{font-family:var(--font-hanzi);margin-bottom:6px;font-size:1.38rem;font-weight:650}.example-block p:last-child{color:var(--muted)}.proper-name{color:var(--proper-name);font-weight:750}.decision-area{justify-content:center;align-items:center;gap:12px;min-height:88px;padding:18px 0;display:flex}.decision-buttons{flex:1;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;display:grid}.reveal-button{min-width:min(100%,320px)}.skip-button{min-height:48px;color:var(--muted);text-decoration:underline;text-decoration-color:var(--border-dark);text-underline-offset:4px;background:0 0;border:0;padding:9px 12px;font-weight:800}kbd{min-width:22px;font-family:var(--font-ui);background:#00000014;border:1px solid #ffffff73;border-radius:5px;padding:2px 5px;font-size:.65rem;font-weight:800;line-height:1.3;display:none}.button-secondary kbd,.skip-button kbd{border-color:var(--border-dark);background:var(--surface-warm)}.empty-state,.summary-card{border:1px solid var(--border);background:var(--surface);min-height:480px;box-shadow:var(--shadow);text-align:center;border-radius:24px;align-content:center;place-items:center;padding:56px;display:grid}.empty-state>span{border:1px solid var(--border);width:70px;height:70px;color:var(--cinnabar);font-family:var(--font-hanzi);border-radius:50%;place-items:center;margin-bottom:22px;font-size:2rem;display:grid}.empty-state h2,.summary-card h2{letter-spacing:-.035em;text-wrap:balance;max-width:19ch;margin:0;font-size:clamp(1.6rem,4vw,2.2rem);line-height:1.18}.empty-state p{max-width:44ch;color:var(--muted);margin:12px 0 24px}.empty-state .button{margin-top:22px}.empty-actions,.summary-actions{flex-wrap:wrap;justify-content:center;gap:10px;margin-top:26px;display:flex}.summary-card{position:relative;overflow:hidden}.summary-mark{color:#a63d320f;font-family:var(--font-hanzi);font-size:12rem;line-height:1;position:absolute;top:-42px;right:-18px}.summary-card .eyebrow{margin-bottom:10px}.summary-stats{flex-wrap:wrap;justify-content:center;gap:32px;margin-top:34px;display:flex}.summary-stats p{gap:3px;margin:0;display:grid}.summary-stats strong{color:var(--cinnabar);font-variant-numeric:tabular-nums;font-size:2rem}.summary-stats span{color:var(--muted);font-size:.8rem}.summary-remaining{max-width:38ch;color:var(--muted);margin:22px 0 0;font-size:.9rem}.queue-loading{gap:16px;display:grid}.queue-loading .loading-progress{margin-top:0}.queue-loading p{color:var(--muted);text-align:center;margin:0}.modal-backdrop{z-index:100;backdrop-filter:blur(3px);background:#191c188a;place-items:center;padding:20px;animation:.14s ease-out both fade-in;display:grid;position:fixed;inset:0}.login-dialog,.help-dialog,.sheet{border:1px solid var(--border);background:var(--surface);border-radius:22px;width:min(440px,100%);padding:32px;box-shadow:0 30px 90px #12141240}.login-dialog{text-align:center;justify-items:center;display:grid}.help-dialog{width:min(620px,100%);max-height:min(760px,100vh - 40px);overflow-y:auto}.help-steps{counter-reset:help-step;gap:12px;margin:0;padding:0;list-style:none;display:grid}.help-steps li{border:1px solid var(--border);background:var(--surface-warm);counter-increment:help-step;border-radius:14px;padding:16px 18px 16px 56px;position:relative}.help-steps li:before{background:var(--cinnabar-soft);width:26px;height:26px;color:var(--cinnabar-dark);content:counter(help-step);border-radius:50%;place-items:center;font-size:.75rem;font-weight:900;display:grid;position:absolute;top:15px;left:17px}.help-steps p{color:var(--muted);margin:4px 0 0;font-size:.9rem}.help-details{gap:10px;margin-top:20px;display:grid}.help-details p{color:var(--muted);margin:0;font-size:.9rem}.help-details p:nth-child(2){background:var(--proper-name-soft);color:var(--ink);border-radius:11px;padding:12px 14px}.sheet-direction-legend{margin-top:2px}.dialog-mark{border:1px solid var(--cinnabar);width:58px;height:58px;color:var(--cinnabar);font-family:var(--font-hanzi);border-radius:14px;place-items:center;margin-bottom:18px;font-size:1.7rem;display:grid}.login-dialog h2,.modal-heading h2{letter-spacing:-.03em;margin:0;font-size:1.7rem}.login-dialog>p{color:var(--muted);margin:12px 0 24px}.google-button{width:100%}.google-button span{color:#3568c0;background:#fff;border-radius:50%;place-items:center;width:25px;height:25px;font-weight:900;display:grid}.login-dialog .config-note{background:var(--amber-soft);color:#65440f;border:1px solid #dec28f;border-radius:10px;padding:12px;font-size:.86rem}.modal-heading{justify-content:space-between;align-items:center;gap:16px;margin-bottom:24px;display:flex}.modal-heading button{background:var(--surface-warm);border:0;border-radius:50%;width:44px;height:44px;font-size:1.35rem}.sheet{gap:18px;display:grid}.toast{z-index:90;border:1px solid var(--border);background:var(--ink);color:#fff;border-radius:12px;align-items:center;gap:12px;max-width:min(420px,100vw - 40px);padding:12px 12px 12px 16px;font-size:.86rem;display:flex;position:fixed;bottom:20px;right:20px;box-shadow:0 20px 60px #00000038}.toast button{color:#fff;background:#ffffff1a;border:0;border-radius:8px;width:38px;height:38px;font-size:1.2rem}.loading-shell{gap:20px;display:grid}.loading-shell p{color:var(--muted);text-align:center}.skeleton{background:#e4ddd1;border-radius:14px;overflow:hidden}.skeleton:after{content:"";background:linear-gradient(90deg,#0000,#ffffff8c,#0000);width:100%;height:100%;animation:1.5s infinite shimmer;display:block}.loading-brand{width:230px;height:52px}.loading-progress{height:54px;margin-top:30px}.loading-card{border-radius:24px;width:min(720px,100%);height:430px;margin:0 auto}.noscript-message{border:1px solid var(--cinnabar);background:var(--cinnabar-soft);max-width:600px;color:var(--ink);font-family:var(--font-ui);text-align:center;border-radius:12px;margin:32px auto;padding:16px}@keyframes reveal{0%{opacity:0;transform:translateY(5px)}to{opacity:1;transform:translateY(0)}}@keyframes fade-in{0%{opacity:0}to{opacity:1}}@keyframes pulse{50%{opacity:.35}}@keyframes shimmer{0%{transform:translate(-100%)}to{transform:translate(100%)}}@media (width>=960px){kbd{display:inline-block}}@media (width<=959px){.app-shell{width:min(100% - 32px,760px);padding-top:18px;padding-bottom:calc(132px + env(safe-area-inset-bottom))}.site-header{align-items:flex-start}.brand small,.sync-label{display:none}.view-tabs{margin-top:18px}.view-tabs button{gap:5px;min-height:52px;font-size:.86rem}.count-pill{min-width:24px;padding:2px 6px}.search-row{margin:20px 0}.filter-trigger{display:inline-flex}.study-layout{display:block}.filter-panel{display:none}.decision-area{z-index:40;min-height:86px;padding:12px max(16px,50vw - 364px);padding-bottom:calc(12px + env(safe-area-inset-bottom));border-top:1px solid var(--border);backdrop-filter:blur(12px);background:#f5f0e6f0;position:fixed;bottom:0;left:0;right:0;box-shadow:0 -10px 35px #3a2d1f14}.decision-buttons{min-width:0}.card-prompt{min-height:360px;padding:42px 48px 48px 60px}.card-answer{padding:36px 44px 42px 60px}.empty-state,.summary-card{min-height:430px}.sheet{width:100%;padding:26px 20px max(24px, env(safe-area-inset-bottom));border-radius:22px 22px 0 0;animation:.18s ease-out both sheet-up;position:absolute;bottom:0;left:0;right:0}@keyframes sheet-up{0%{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}}@media (width<=600px){.app-shell{width:calc(100% - 24px)}.view-tabs{border:1px solid var(--border);background:#fffcf594;border-radius:16px;grid-template-columns:repeat(2,minmax(0,1fr));gap:8px;padding:8px}.view-tabs button{background:var(--surface);border:1px solid #0000;border-radius:10px;justify-content:space-between;min-height:48px;padding:8px 10px;font-size:.86rem}.view-tabs button:after{display:none}.view-tabs button:hover{background:var(--surface-warm)}.view-tabs button.is-active{background:var(--cinnabar-soft);border-color:#a63d323d}.view-tabs .count-pill,.view-tabs .is-active .count-pill{background:#6670691a}.brand-mark{width:42px;height:42px}.brand strong{font-size:.94rem}.button-small{min-height:42px;padding:7px 10px;font-size:.76rem}.guest-note{flex-wrap:wrap;align-items:flex-start}.guest-note p{min-width:calc(100% - 46px)}.guest-note .text-button{min-height:36px;margin-left:42px;padding:0}.search-row{gap:8px}.filter-trigger{min-width:82px;padding:10px 12px}.session-progress>div:first-child{align-items:flex-start}.direction-badge{white-space:nowrap}.study-card{border-radius:19px}.study-card:before{left:22px}.card-prompt{min-height:330px;padding:36px 32px 42px 42px}.card-answer{background:linear-gradient(90deg, transparent 0, transparent 22px, #a63d3214 22px, #a63d3214 23px, transparent 23px), var(--surface-warm);padding:32px 25px 36px 42px}.answer-details>div{grid-template-columns:1fr;gap:4px}.example-block{padding:18px}.decision-area{padding-left:12px;padding-right:12px}.decision-buttons{gap:7px}.decision-buttons .button{min-width:0;padding:10px 8px;font-size:.78rem}.skip-button{padding:7px 5px;font-size:.78rem}.empty-state,.summary-card{min-height:390px;padding:40px 22px}.summary-stats{gap:18px}.summary-stats p{min-width:110px}.login-dialog{padding:28px 22px}.help-dialog{max-height:calc(100vh - 24px);padding:26px 20px}.help-steps li{padding:14px 14px 14px 50px}}@media (width<=370px){.brand strong{max-width:88px;line-height:1.1}.search-field input{padding-left:40px;font-size:.86rem}.filter-trigger{min-width:72px;font-size:.78rem}}@media (prefers-reduced-motion:reduce){*,:before,:after{scroll-behavior:auto!important;transition-duration:.01ms!important;animation-duration:.01ms!important;animation-iteration-count:1!important}}