:root{--ink:#16181d;--ink-soft:#5b6472;--ink-faint:#8b93a1;--line:#dfe3ea;--surface:#ffffff;--surface-sunk:#f4f6f9;--accent:#1f2937;--danger:#b42318;--danger-soft:#fef3f2;--warn:#b54708;--warn-soft:#fffaeb;--ok:#067647;--ok-soft:#ecfdf3;--radius:8px;--tap:44px;--gap:16px;--nav-height:60px;--sidebar-width:200px;--font-body:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;--text-sm:13px;--text-base:15px;--text-lg:18px;--text-xl:22px}*,:after,:before{box-sizing:border-box}body,html{margin:0;padding:0}html{-webkit-text-size-adjust:100%}body{font-family:var(--font-body);font-size:var(--text-base);line-height:1.5;color:var(--ink);background:var(--surface-sunk);min-height:100dvh}button{font:inherit}a,button{color:inherit}:focus-visible{outline:2px solid var(--accent);outline-offset:2px}.visually-hidden{position:absolute;width:1px;height:1px;margin:-1px;padding:0;overflow:hidden;-webkit-clip-path:inset(50%);clip-path:inset(50%);white-space:nowrap}.login-screen{display:flex;flex-direction:column;justify-content:center;min-height:100dvh;padding:24px 20px calc(24px + env(safe-area-inset-bottom));background:var(--surface)}.login-card{width:100%;max-width:400px;margin:0 auto}.login-title{margin:0 0 28px;font-size:var(--text-xl);font-weight:600;text-align:center}.field{margin-bottom:18px}.field-label{display:block;margin-bottom:6px;font-size:var(--text-sm);font-weight:600;color:var(--ink-soft)}.field-row{display:flex;gap:8px}.field-input{width:100%;min-height:var(--tap);padding:10px 12px;border:1px solid var(--line);border-radius:var(--radius);background:var(--surface);color:var(--ink);font-size:16px}.field-input:disabled{background:var(--surface-sunk);color:var(--ink-faint)}.field-input.has-error{border-color:var(--danger)}.field-error{display:block;margin-top:6px;font-size:var(--text-sm);color:var(--danger)}.reveal-button{flex:0 0 auto;min-width:var(--tap);min-height:var(--tap);border:1px solid var(--line);border-radius:var(--radius);background:var(--surface);cursor:pointer}.reveal-button:disabled{background:var(--surface-sunk);cursor:default}.submit-button{width:100%;min-height:var(--tap);margin-top:6px;border:0;border-radius:var(--radius);background:var(--accent);color:#fff;font-size:var(--text-base);font-weight:600;cursor:pointer}.submit-button[data-pending=true]{opacity:.7;cursor:default}.form-alert{margin-bottom:18px;padding:12px 14px;border:1px solid var(--line);border-radius:var(--radius);font-size:var(--text-sm)}.form-alert[data-tone=danger]{border-color:var(--danger);background:var(--danger-soft);color:var(--danger)}.form-alert[data-tone=warn]{border-color:var(--warn);background:var(--warn-soft);color:var(--warn)}.form-alert[data-tone=info]{background:var(--surface-sunk);color:var(--ink-soft)}.form-alert-action{margin-top:10px;margin-right:8px;min-height:36px;padding:0 14px;border:1px solid;border-radius:var(--radius);background:transparent;color:inherit;font:inherit;cursor:pointer}.form-alert-action.is-quiet{border-color:transparent;text-decoration:underline}.forgot-row{margin-top:22px;text-align:center}.forgot-button{min-height:var(--tap);padding:0 8px;border:0;background:transparent;color:var(--ink-soft);text-decoration:underline;cursor:pointer}.forgot-answer{margin-top:10px;padding:12px 14px;border-radius:var(--radius);background:var(--surface-sunk);color:var(--ink-soft);font-size:var(--text-sm);text-align:left}.app-shell{display:flex;flex-direction:column;min-height:100dvh}.connection-banner{padding:8px 16px;font-size:var(--text-sm);text-align:center}.connection-banner[data-status=offline]{background:var(--warn-soft);color:var(--warn)}.connection-banner[data-status=restored]{background:var(--ok-soft);color:var(--ok)}.app-body{display:flex;flex:1 1 auto;min-height:0}.app-main{flex:1 1 auto;width:100%;padding:0 16px calc(var(--nav-height) + 24px + env(safe-area-inset-bottom));background:var(--surface-sunk)}.app-header{display:flex;align-items:center;gap:8px;min-height:56px;padding:8px 0}.app-header-title{margin:0;font-size:var(--text-lg);font-weight:600}.app-header-sep{color:var(--ink-faint)}.app-header-action{margin-left:auto;display:inline-flex;align-items:center;min-height:38px;padding:0 12px;border:1px solid var(--line);border-radius:var(--radius);background:var(--surface);color:var(--ink);text-decoration:none;cursor:pointer}.account-menu{position:relative}.account-trigger{min-height:38px;padding:0 8px;border:0;border-radius:var(--radius);background:transparent;color:var(--ink-soft);cursor:pointer}.account-panel{position:absolute;z-index:20;top:calc(100% + 4px);left:0;min-width:200px;padding:8px;border:1px solid var(--line);border-radius:var(--radius);background:var(--surface);box-shadow:0 6px 20px rgb(16 24 40/12%)}.account-panel-item{display:block;width:100%;min-height:var(--tap);padding:0 10px;border:0;border-radius:var(--radius);background:transparent;text-align:left;cursor:pointer}.account-confirm-text{margin:0 0 10px;padding:0 10px;font-size:var(--text-sm);color:var(--ink-soft)}.account-confirm-row{display:flex;gap:8px}.account-confirm-row button{flex:1 1;min-height:40px;border:1px solid var(--line);border-radius:var(--radius);background:var(--surface);cursor:pointer}.account-confirm-row button[data-tone=danger]{border-color:var(--danger);color:var(--danger)}.bottom-nav{position:fixed;z-index:30;right:0;bottom:0;left:0;display:flex;border-top:1px solid var(--line);background:var(--surface);padding-bottom:env(safe-area-inset-bottom)}.bottom-nav-item{display:flex;flex:1 1;align-items:center;justify-content:center;min-height:var(--nav-height);color:var(--ink-soft);font-size:var(--text-sm);text-decoration:none}.bottom-nav-item[aria-current=page]{color:var(--ink);font-weight:600;box-shadow:inset 0 2px 0 var(--accent)}.side-nav{display:none}.skeleton{border-radius:var(--radius);background:linear-gradient(90deg,#e9edf3 25%,#f2f5f9 37%,#e9edf3 63%);background-size:400% 100%;animation:skeleton-sweep 1.4s ease infinite}@keyframes skeleton-sweep{0%{background-position:100% 50%}to{background-position:0 50%}}@media (prefers-reduced-motion:reduce){.skeleton{animation:none}}.skeleton-stack{display:flex;flex-direction:column;gap:12px}.error-state{padding:20px;border:1px solid var(--line);border-radius:var(--radius);background:var(--surface);text-align:center}.error-state-title{margin:0 0 12px;font-size:var(--text-base)}.error-state-action{min-height:40px;padding:0 16px;border:1px solid var(--line);border-radius:var(--radius);background:var(--surface);cursor:pointer}.empty-state{padding:48px 20px 32px;text-align:center}.empty-state-title{margin:0;font-size:var(--text-lg);font-weight:600}.empty-state-body{max-width:40ch;margin:10px auto 0;color:var(--ink-soft)}.empty-state-action{margin-top:24px}.empty-state-button{display:inline-block;min-width:200px;min-height:var(--tap);padding:12px 24px;border:1px solid var(--line);border-radius:var(--radius);background:var(--surface);color:var(--ink);font-weight:600;text-align:center;text-decoration:none;cursor:pointer}.empty-state-truth>summary{list-style:none}.empty-state-truth>summary::-webkit-details-marker{display:none}.empty-state-answer{max-width:40ch;margin:12px auto 0;padding:12px 14px;border-radius:var(--radius);background:var(--surface);color:var(--ink-soft);font-size:var(--text-sm);text-align:left}.class-list{margin:0;padding:0;list-style:none}.class-list>li{margin-bottom:12px;border:1px solid var(--line);border-radius:var(--radius);background:var(--surface)}.class-row-open{display:block;width:100%;padding:14px 16px;border:0;border-radius:inherit;background:transparent;font:inherit;color:inherit;text-align:left;cursor:pointer}.class-row-code{display:block;font-weight:600}.class-row-course,.class-row-line{display:block;margin-top:2px;color:var(--ink-soft)}.class-row-line{font-size:var(--text-sm)}.class-list-foot{margin-top:20px;text-align:center}.field-optional{font-weight:400;color:var(--ink-faint)}.field-hint{display:block;margin-top:6px;font-size:var(--text-sm);color:var(--ink-soft)}.field-input[data-locked=true]{background:var(--surface-sunk);color:var(--ink-soft)}.field-pair{display:contents}.form-panel{margin-bottom:20px;padding:16px;border:1px solid var(--line);border-radius:var(--radius);background:var(--surface)}.form-panel-title{margin:0 0 16px;font-size:var(--text-lg);font-weight:600}.form-alert-body{color:inherit}.form-actions{display:flex;flex-direction:column;gap:10px;margin-top:20px}.ghost-button{width:100%;min-height:var(--tap);border:1px solid var(--line);border-radius:var(--radius);background:var(--surface);color:var(--ink);font-weight:600;cursor:pointer}.ghost-button:disabled{color:var(--ink-faint);cursor:default}.form-done{display:flex;flex-wrap:wrap;align-items:center;gap:10px;margin-bottom:16px;padding:12px 14px;border:1px solid var(--ok);border-radius:var(--radius);background:var(--ok-soft);color:var(--ok);font-size:var(--text-sm)}.form-done .form-alert-action{display:inline-flex;align-items:center;margin-top:0;text-decoration:none}.just-added{margin:20px 0 0;padding-top:14px;border-top:1px solid var(--line);color:var(--ink-soft);font-size:var(--text-sm);display:-webkit-box;-webkit-box-orient:vertical;-webkit-line-clamp:2;line-clamp:2;overflow:hidden}.filter-chips{display:flex;gap:8px;margin-bottom:16px;padding-bottom:4px;overflow-x:auto;-webkit-overflow-scrolling:touch}.filter-chip{flex:0 0 auto;min-height:40px;padding:0 14px;border:1px solid var(--line);border-radius:999px;background:var(--surface);color:var(--ink-soft);cursor:pointer;white-space:nowrap}.filter-chip[aria-pressed=true]{border-color:var(--accent);background:var(--accent);color:#fff;font-weight:600}.student-list{margin:0;padding:0;list-style:none}.student-list-item{border-bottom:1px solid var(--line)}.student-row-open{display:block;width:100%;min-height:44px;padding:12px 0;border:0;background:transparent;font:inherit;color:inherit;text-align:left;cursor:pointer}.student-row-name{display:block;font-weight:600}.student-row-meta{display:block;margin-top:2px}.list-total,.student-row-meta{color:var(--ink-soft);font-size:var(--text-sm)}.list-total{margin:20px 0 0;text-align:center}.list-note{margin:32px 0;color:var(--ink-soft);text-align:center}.student-workbench[data-form-open=true] .student-list-panel{display:none}@keyframes card-flash{0%{background:var(--ok-soft);border-color:var(--ok)}to{background:var(--surface);border-color:var(--line)}}.class-list-item[data-fresh=true]{animation:card-flash 1.8s ease-out 1}@media (prefers-reduced-motion:reduce){.class-list-item[data-fresh=true]{animation:none;border-color:var(--ok)}}.class-list-item[data-finished=true] .class-row-code,.class-list-item[data-finished=true] .class-row-course,.class-list-item[data-finished=true] .class-row-line{color:var(--ink-faint)}@media (min-width:768px){.bottom-nav{display:none}.side-nav{display:flex;flex:0 0 var(--sidebar-width);flex-direction:column;gap:4px;padding:16px 12px;border-right:1px solid var(--line);background:var(--surface)}.side-nav-item{display:flex;align-items:center;min-height:var(--tap);padding:0 12px;border-radius:var(--radius);color:var(--ink-soft);text-decoration:none}.side-nav-item[aria-current=page]{background:var(--surface-sunk);color:var(--ink);font-weight:600}.side-nav-foot{margin-top:auto;padding-top:12px;border-top:1px solid var(--line)}.app-main{max-width:720px;padding:0 24px 40px}.account-menu[data-place=header],.app-header-sep{display:none}.login-screen{padding:40px 24px}.field-pair{display:grid;grid-template-columns:1fr 1fr;grid-gap:0 16px;gap:0 16px}.form-panel{padding:24px}.form-actions{flex-direction:row;align-items:center}.ghost-button,.submit-button{width:auto;min-width:180px;padding:0 24px}}@media (min-width:1024px){:root{--sidebar-width:240px;--text-base:16px;--text-lg:20px;--text-xl:26px}.app-main{max-width:960px;padding:0 32px 56px}.app-header{min-height:68px}.class-list{display:grid;grid-template-columns:1fr 1fr;grid-gap:12px;gap:12px}.class-list>li{margin-bottom:0}.student-workbench{display:grid;grid-template-columns:minmax(320px,400px) 1fr;grid-column-gap:28px;column-gap:28px;align-items:start}.student-workbench>.app-header{grid-column:1/-1}.student-workbench>.form-panel{grid-column:1}.student-workbench>.student-list-panel{grid-column:2}.student-workbench[data-form-open=false]>.student-list-panel{grid-column:1/-1}.student-workbench[data-form-open=true] .student-list-panel{display:block}.student-workbench .form-actions{flex-direction:column;align-items:stretch}.student-workbench .ghost-button,.student-workbench .submit-button{width:100%;min-width:0}}@media (max-width:767px){.account-menu[data-place=sidebar]{display:none}}