:root{--bg1:#eef6ff;--bg2:#daeaff;--season-bg:url("./backgrounds/winter.svg");--ink:#152033;--muted:#66758d;--glass:rgba(255,255,255,.58);--glass-strong:rgba(255,255,255,.76);--line:rgba(255,255,255,.72);--accent:#4d83d7;--accent2:#87afe9;--danger:#c74f60;--shadow:0 24px 70px rgba(35,67,105,.15);--radius:24px}
html[data-theme="spring"]{--season-bg:url("./backgrounds/spring.svg");--bg1:#fff1f6;--bg2:#e8f6e9;--accent:#d45f8c;--accent2:#86bd8c;--ink:#402b38}
html[data-theme="summer"]{--season-bg:url("./backgrounds/summer.svg");--bg1:#e9fbff;--bg2:#dff7ee;--accent:#178aa0;--accent2:#3db8a2;--ink:#153b43}
html[data-theme="autumn"]{--season-bg:url("./backgrounds/autumn.svg");--bg1:#fff4e3;--bg2:#ecd8bd;--accent:#bd672f;--accent2:#d79543;--ink:#482f22}
html[data-theme="winter"]{--season-bg:url("./backgrounds/winter.svg");--bg1:#edf6ff;--bg2:#dfeafa;--accent:#527fc1;--accent2:#8fb4e4;--ink:#172b46}
html[data-theme="off"]{--season-bg:none;--bg1:#f3f4f6;--bg2:#e5e7eb;--accent:#3f4650;--accent2:#747b84;--ink:#20242a}
*{box-sizing:border-box}html,body{margin:0;min-height:100%;font-family:Inter,Pretendard,"Noto Sans KR",system-ui,sans-serif;color:var(--ink)}body{min-height:100vh;background-color:var(--bg2);background-image:linear-gradient(145deg,rgba(255,255,255,.30),rgba(255,255,255,.08)),var(--season-bg),linear-gradient(145deg,var(--bg1),var(--bg2));background-size:cover,cover,cover;background-position:center;background-attachment:fixed;transition:background-color .45s ease,color .35s ease;color:var(--ink)}body::before,body::after{content:"";position:fixed;border-radius:999px;filter:blur(70px);opacity:.35;pointer-events:none;z-index:-2}body::before{width:38vw;height:38vw;left:-8vw;top:-12vw;background:var(--accent2)}body::after{width:34vw;height:34vw;right:-8vw;bottom:-10vw;background:var(--accent)}html.no-background body{background:#f4f5f7;background-image:none}html.no-background body::before,html.no-background body::after{display:none}button,input,textarea,select{font:inherit}button{color:inherit}a{color:var(--accent)}#effectCanvas{position:fixed;inset:0;width:100%;height:100%;z-index:-1;pointer-events:none}.shell{width:min(1120px,calc(100% - 28px));margin:0 auto;padding:18px 0 44px}.legacy-note{text-align:center;font-size:13px;color:var(--muted);padding:4px 8px 12px}.legacy-note a{font-weight:700;text-underline-offset:3px}.glass{background:var(--glass);border:1px solid var(--line);box-shadow:var(--shadow);backdrop-filter:blur(22px) saturate(135%);-webkit-backdrop-filter:blur(22px) saturate(135%)}.topbar{border-radius:22px;padding:14px 16px;display:flex;align-items:center;justify-content:space-between;gap:12px;position:sticky;top:10px;z-index:5}.brand-wrap{display:flex;align-items:center;gap:11px}.brand-mark{width:40px;height:40px;border-radius:14px;display:grid;place-items:center;font-weight:900;color:white;background:linear-gradient(135deg,var(--accent),var(--accent2));box-shadow:0 8px 22px color-mix(in srgb,var(--accent) 28%,transparent)}h1,h2{margin:0}h1{font-size:18px}.micro,.status,.keyhint{font-size:12px;color:var(--muted)}.top-actions,.study-toolbar,.nav-actions,.composer-actions,.section-head{display:flex;align-items:center;gap:8px}.grid{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin-top:16px}.composer,.study-panel,.cards-panel{border-radius:var(--radius);padding:18px}.cards-panel{grid-column:1/-1}.field{margin-bottom:13px}.field label{font-size:12px;color:var(--muted);display:block;margin-bottom:6px}.field input,.field textarea,select{width:100%;border:1px solid rgba(255,255,255,.75);outline:none;background:rgba(255,255,255,.68);border-radius:15px;padding:13px 14px;color:var(--ink);box-shadow:inset 0 1px 0 rgba(255,255,255,.75)}.field input:focus,.field textarea:focus,select:focus{border-color:color-mix(in srgb,var(--accent) 55%,white);box-shadow:0 0 0 4px color-mix(in srgb,var(--accent) 14%,transparent)}textarea{min-height:110px;resize:vertical}.composer-actions{justify-content:flex-end}.composer-actions .status{margin-right:auto}.keyhint{margin-top:11px;text-align:right}kbd{padding:2px 5px;border-radius:6px;border:1px solid rgba(0,0,0,.12);background:rgba(255,255,255,.65);font-size:11px}.btn,.icon-btn{border:1px solid rgba(255,255,255,.7);min-height:44px;border-radius:14px;cursor:pointer;transition:transform .15s ease,box-shadow .2s ease,background .2s ease}.btn{padding:10px 14px;font-weight:750}.icon-btn{width:44px;padding:0;background:rgba(255,255,255,.52);font-weight:900}.btn:hover,.icon-btn:hover{transform:translateY(-1px);box-shadow:0 8px 18px rgba(30,50,70,.1)}.btn:active,.icon-btn:active{transform:translateY(1px)}.btn:focus-visible,.icon-btn:focus-visible,.flip:focus-visible{outline:3px solid color-mix(in srgb,var(--accent) 35%,transparent);outline-offset:2px}.btn.primary{background:linear-gradient(135deg,var(--accent),var(--accent2));color:white;border-color:transparent}.btn.secondary{background:color-mix(in srgb,var(--accent) 13%,rgba(255,255,255,.65));color:var(--ink)}.btn.ghost{background:rgba(255,255,255,.45)}.btn.danger{color:var(--danger)}.dot{width:8px;height:8px;border-radius:50%;background:#adb5bd;display:inline-block}.dot.on{background:#22a66b;box-shadow:0 0 0 4px rgba(34,166,107,.12)}.study-toolbar{justify-content:space-between}.stage{display:grid;place-items:center;padding:24px 0 10px}.flip{width:min(100%,390px);height:240px;border:0;background:none;perspective:1000px;cursor:pointer;padding:0}.flip-inner{position:relative;display:block;width:100%;height:100%;transform-style:preserve-3d;transition:transform .5s cubic-bezier(.2,.7,.2,1)}.flip.is-flipped .flip-inner{transform:rotateY(180deg)}.face{position:absolute;inset:0;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:10px;border-radius:26px;background:var(--glass-strong);border:1px solid rgba(255,255,255,.8);box-shadow:0 18px 45px rgba(29,49,75,.13);backface-visibility:hidden;padding:24px}.face.back{transform:rotateY(180deg)}.face strong{font-size:clamp(25px,4vw,38px);text-align:center}.face small{color:var(--muted)}.section-head{justify-content:space-between;margin-bottom:12px}.section-head h2{font-size:16px}.card-list{display:grid;grid-template-columns:repeat(auto-fill,minmax(230px,1fr));gap:10px}.item{padding:14px;border-radius:17px;background:rgba(255,255,255,.58);border:1px solid rgba(255,255,255,.76)}.item h3{font-size:15px;margin:0 0 7px}.item p{font-size:13px;line-height:1.5;color:var(--muted);white-space:pre-wrap;margin:0 0 12px}.item-actions{display:flex;gap:7px}.item-actions button{min-height:36px;padding:7px 10px}.settings-dialog{width:min(440px,calc(100% - 26px));border-radius:24px;color:var(--ink);padding:0;border:1px solid var(--line)}.settings-dialog::backdrop{background:rgba(25,35,48,.25);backdrop-filter:blur(4px)}.settings-dialog form{padding:18px}.dialog-head{display:flex;align-items:center;justify-content:space-between;margin-bottom:10px}.dialog-head h2{font-size:18px}.settings-grid{display:grid;gap:2px}.setting-row{min-height:54px;display:flex;align-items:center;justify-content:space-between;gap:14px;border-bottom:1px solid rgba(255,255,255,.55)}.setting-row select{width:150px;padding:9px 10px}.setting-row input[type=checkbox]{appearance:none;width:46px;height:27px;border-radius:999px;background:#b7bdc5;position:relative;cursor:pointer;transition:.2s}.setting-row input[type=checkbox]::after{content:"";width:21px;height:21px;background:white;border-radius:50%;position:absolute;top:3px;left:3px;box-shadow:0 2px 7px rgba(0,0,0,.2);transition:.2s}.setting-row input[type=checkbox]:checked{background:var(--accent)}.setting-row input[type=checkbox]:checked::after{transform:translateX(19px)}
@media(max-width:760px){.shell{width:min(100% - 18px,700px);padding-top:10px}.topbar{top:6px}.grid{grid-template-columns:1fr}.cards-panel{grid-column:auto}.top-actions #toggleAuto span:last-child{display:none}.composer,.study-panel,.cards-panel{padding:14px}.keyhint{display:none}.flip{height:210px}.legacy-note{font-size:12px}.card-list{grid-template-columns:1fr}.composer-actions{flex-wrap:wrap}.composer-actions .status{width:100%;min-height:16px}}
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