:root{--night:#141B3D;--night2:#232F6B;--star:#F2BE4B;--ink:#181E33;--muted:#5C6480;--line:#E2E5F0;--bg:#F4F5FA;--accent:#3346C8;--ui:Figtree,system-ui,-apple-system,'Hiragino Sans','Noto Sans JP',sans-serif;--serif:Literata,Georgia,serif}
*{box-sizing:border-box}html{-webkit-text-size-adjust:100%}body{margin:0;font:16px/1.5 var(--ui);color:var(--ink);background:var(--bg);-webkit-font-smoothing:antialiased}a{color:inherit;text-decoration:none}
:focus-visible{outline:3px solid #8FA0FF;outline-offset:3px;border-radius:6px}
/* ログイン */
body.mode-login,body.mode-denied,body.mode-https{background:radial-gradient(1.5px 1.5px at 18% 22%,#fff9,transparent),radial-gradient(1px 1px at 72% 16%,#fff8,transparent),radial-gradient(2px 2px at 84% 62%,#ffe08a,transparent),radial-gradient(1px 1px at 30% 74%,#fff7,transparent),linear-gradient(180deg,var(--night),var(--night2));min-height:100dvh}
.gate{min-height:100dvh;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:28px;padding:24px 16px}
.gate-brand{display:flex;flex-direction:column;align-items:center;gap:10px;color:#fff}.gate-brand .mark{width:68px;height:68px}.gate-brand h1{margin:0;font:600 34px/1.1 var(--serif);letter-spacing:.01em}
.panel{width:min(380px,100%);background:#fff;border-radius:16px;padding:26px 26px 22px;box-shadow:0 24px 70px #0b102a59}.panel p{margin:0 0 14px}
.panel label{display:block;font-size:14px;font-weight:600;margin-bottom:6px}.panel input[type=text],.panel input[type=password]{width:100%;padding:12px 14px;border:1px solid var(--line);border-radius:10px;font:16px var(--ui);background:#FBFBFE}.panel input:focus{outline:2px solid var(--accent);outline-offset:0;border-color:var(--accent)}
.panel .login-remember{font-size:14px;color:var(--muted)}.panel .login-remember label{font-weight:400;margin:0}.panel input[type=submit]{width:100%;padding:13px;border:0;border-radius:10px;background:var(--accent);color:#fff;font:600 16px var(--ui);cursor:pointer}.panel input[type=submit]:hover{background:#2636A6}
.panel.msg{text-align:center}.panel.msg h2{margin:0 0 6px;font:600 22px var(--serif)}.panel.msg p{color:var(--muted)}.logout-light{color:var(--accent);font-size:14px}
.grid.learn,.grid.practice{grid-template-columns:repeat(3,minmax(0,1fr))}.grid.reference{grid-template-columns:repeat(4,minmax(0,1fr))}
/* ホーム */
.top{display:flex;align-items:center;justify-content:space-between;height:64px;padding:0 max(calc((100vw - 1120px)/2),20px);background:var(--night);color:#fff}
.brand{display:flex;align-items:center;gap:10px;font:600 19px var(--serif)}.brand .mark{width:36px;height:36px;border-radius:9px}.logout{color:#C9D0F2;font-size:15px}.logout:hover{color:#fff}
.home{max-width:1120px;margin:0 auto;padding:34px 20px 60px}.home h1{margin:0 0 26px;font:600 clamp(26px,5vw,34px)/1.2 var(--serif)}
.group{margin-top:30px}.group h2{margin:0 0 12px;font:600 14px var(--ui);color:var(--muted)}
.grid{display:grid;gap:14px;grid-template-columns:repeat(3,minmax(0,1fr))}.grid.reference{grid-template-columns:repeat(4,minmax(0,1fr))}
.tile{position:relative;display:flex;align-items:center;gap:14px;min-height:84px;padding:14px 16px;background:#fff;border:1px solid var(--line);border-radius:14px;transition:transform .14s,box-shadow .14s,border-color .14s}
a.tile:hover{transform:translateY(-2px);box-shadow:0 10px 26px #141b3d1f;border-color:#C9CFE6}
.ico{flex:none;display:grid;place-items:center;width:48px;height:48px;border-radius:13px;color:#fff}.ico svg{width:26px;height:26px}
.night .ico{background:var(--night);color:var(--star)}.teal .ico{background:#177A6B}.indigo .ico{background:var(--accent)}.green .ico{background:#3A8C4F}.sky .ico{background:#2F86D6}.amber .ico{background:#D98A1F}.plum .ico{background:#7B5BD6}.coral .ico{background:#D9604A}.slate .ico{background:#47536F}.plain .ico{background:#ECEEF8;color:var(--night)}
.tile.big{min-height:128px;padding:20px 22px}.tile.big .ico{width:64px;height:64px;border-radius:17px}.tile.big .ico svg{width:34px;height:34px}.tile.big strong{font-size:22px}
.txt{display:block;min-width:0}.txt strong{display:block;font-size:17px;font-weight:700;line-height:1.25}.txt small{display:block;color:var(--muted);font-size:13px;margin-top:2px}
.tile em{position:absolute;right:12px;top:10px;font:500 11px var(--ui);color:var(--muted)}
@media(max-width:900px){.grid,.grid.learn,.grid.practice{grid-template-columns:repeat(2,minmax(0,1fr))}.grid.reference{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:560px){.home{padding:24px 16px 44px}.grid,.grid.learn,.grid.practice,.grid.reference{grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}.tile{flex-direction:column;align-items:flex-start;gap:10px;padding:14px;min-height:124px}.tile.big{grid-column:1/-1;flex-direction:row;align-items:center;min-height:96px;padding:16px}.tile.big .ico{width:56px;height:56px}.tile em{top:8px;right:10px}}
@media(prefers-reduced-motion:reduce){*{transition:none!important}}