:root{--ink:#19365c;--muted:#6f819b;--blue:#276be8;--blue-dark:#1756c7;--line:#dce8f7;--paper:#fff;--sky:#f4f9ff;--mint:#2fbd93;--mint-bg:#e6f9f0;--amber:#d78922;--amber-bg:#fff4df;--shadow:0 12px 34px rgba(28,71,133,.09)}
*{box-sizing:border-box}html{font-size:16px}body{margin:0;min-width:320px;background:var(--sky);color:var(--ink);font-family:"Microsoft YaHei","PingFang SC","Noto Sans CJK SC",system-ui,sans-serif}button,input,select{font:inherit}button{cursor:pointer}button:focus-visible,input:focus-visible,select:focus-visible{outline:3px solid #ffbd3e;outline-offset:3px}[hidden]{display:none!important}
.site-shell{min-height:100vh;background:radial-gradient(circle at 8% 5%,#e1f3ff 0,transparent 25%),radial-gradient(circle at 92% 5%,#fff0cb 0,transparent 19%),#f4f9ff;position:relative;overflow:hidden}.site-shell:before,.site-shell:after{content:"✦";position:absolute;pointer-events:none;color:#b9dcff;font-size:23px;top:124px;left:4%;animation:twinkle 4s ease-in-out infinite}.site-shell:after{left:auto;right:7%;top:217px;color:#f5d982;font-size:17px;animation-delay:1.4s}.topbar{height:82px;padding:0 clamp(20px,4vw,60px);background:rgba(255,255,255,.94);border-bottom:1px solid #dfeaf6;display:flex;align-items:center;justify-content:space-between;gap:15px;position:relative;z-index:3}.brand{display:flex;align-items:center;gap:13px;font-weight:900;letter-spacing:.02em;font-size:23px;white-space:nowrap}.brand-icon{width:46px;height:46px;border-radius:15px;display:grid;place-items:center;background:var(--blue);color:#fff;font-size:31px;box-shadow:0 5px 0 #a9c7f4;transform:rotate(-7deg)}.top-actions{display:flex;align-items:center;gap:17px}.connection{border:0;display:inline-flex;align-items:center;gap:7px;border-radius:99px;background:#e7f8f1;color:#16846e;font-size:14px;font-weight:800;padding:9px 13px;white-space:nowrap}.connection:before{content:"";width:8px;height:8px;background:#34ba91;border-radius:50%}.connection.offline{background:#fff0d9;color:#a56b18}.connection.offline:before{background:#efa335}.connection.syncing{background:#e8f0ff;color:#2864d1}.connection.syncing:before{background:#3d81e8;animation:pulse 1s infinite}.connection.error{background:#ffe8e8;color:#b83e4a}.connection.error:before{background:#dc5861}.teacher-toggle,.secondary-button{background:#fff;border:1.5px solid #dce6f4;border-radius:14px;color:#315377;font-weight:800;padding:11px 16px;display:inline-flex;align-items:center;justify-content:center;gap:8px;white-space:nowrap;transition:transform .18s,box-shadow .18s}.teacher-toggle:hover,.secondary-button:hover{transform:translateY(-2px);box-shadow:0 7px 14px #315d9a18}.teacher-toggle span:first-child{font-size:21px;line-height:1}
.workspace,.teacher-layout{max-width:1460px;margin:0 auto;padding:34px clamp(20px,4vw,58px) 36px;position:relative;z-index:1}.page-head,.teacher-heading{display:flex;align-items:end;justify-content:space-between;gap:20px;margin-bottom:26px}.eyebrow{margin:0 0 7px;font-weight:900;font-size:15px;letter-spacing:.03em;color:#2874df}.eyebrow span{color:#f5af33}.page-head h1,.teacher-heading h1{font-size:clamp(30px,3.1vw,43px);line-height:1.22;margin:0;letter-spacing:-.035em;font-weight:950}.select-label{display:flex;flex-direction:column;gap:7px;color:#647a97;font-size:14px;font-weight:800}.select-label select{min-width:212px;background:#fff;border:1.5px solid #d5e3f4;color:var(--ink);border-radius:14px;padding:12px 35px 12px 14px;font-size:16px;font-weight:800}.assignment-row{display:flex;align-items:center;gap:12px;flex-wrap:wrap;margin-bottom:24px}.row-label{font-size:16px;font-weight:900;white-space:nowrap}.assignment-tabs{display:flex;align-items:center;gap:10px;flex-wrap:wrap}.assignment-pill{border:1.5px solid #dce7f5;color:#466489;background:#fff;padding:12px 19px;border-radius:99px;font-weight:850;font-size:15px;transition:transform .16s,background .16s}.assignment-pill:hover{transform:translateY(-2px)}.assignment-pill.active{color:white;border-color:var(--blue);background:var(--blue);box-shadow:0 5px 0 #b7cdf2}.assignment-pill.archived:after{content:" · 已归档";font-size:13px;opacity:.8}.assignment-date{margin-left:auto;color:#7288a2;font-size:14px;font-weight:800}.progress-card{display:grid;grid-template-columns:auto minmax(120px,1fr) auto;gap:26px;align-items:center;padding:24px 28px;background:white;border:1px solid #dfebf7;box-shadow:var(--shadow);border-radius:25px;margin-bottom:22px}.progress-copy{display:flex;align-items:baseline;gap:13px;white-space:nowrap}.progress-copy>span:first-child{font-weight:900;color:#496789}.progress-copy strong{font-size:39px;line-height:1;color:#2773e2;font-weight:950}.progress-copy small{font-size:19px;color:#9bacbf}.progress-copy>span:last-child{font-size:14px;font-weight:800;color:#6c819d}.progress-bar{height:14px;background:#e9f1fb;border-radius:20px;overflow:hidden}.progress-bar span{display:block;height:100%;background:linear-gradient(90deg,#56d9b4,#27b990);border-radius:20px;min-width:0;transition:width .45s cubic-bezier(.2,.8,.2,1)}.progress-hint{margin:0;font-size:14px;color:#627d9b;font-weight:800;white-space:nowrap}.progress-hint span{color:#f0b63b}.group-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px}.group-card{background:#fff;border:1px solid #dce8f7;border-radius:25px;padding:24px;box-shadow:0 9px 25px #2258990e;min-width:0}.group-card-head{display:flex;align-items:center;gap:13px;margin-bottom:21px}.group-number{height:49px;width:49px;border-radius:16px;display:grid;place-items:center;font-size:23px;font-weight:950;background:#e5f2ff;color:#3475df;flex-shrink:0}.group-card:nth-child(3n+2) .group-number{background:#fff0d8;color:#df982e}.group-card:nth-child(3n) .group-number{background:#e5f8ed;color:#28a979}.group-card-head h2{font-size:21px;margin:0 0 3px;font-weight:950;line-height:1.25}.group-card-head p{margin:0;font-size:14px;font-weight:800;color:#7b8da7}.student-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}.student-card{background:#f9fbff;border:1.5px solid #e2eaf6;border-radius:17px;min-height:83px;padding:12px 13px;display:flex;flex-direction:column;align-items:flex-start;justify-content:space-between;gap:5px;color:#315075;text-align:left;transition:transform .18s,box-shadow .18s,background .18s;touch-action:manipulation;position:relative}.student-card:hover{transform:translateY(-2px);box-shadow:0 8px 15px #2b5b9d16}.student-card:active{transform:scale(.96)}.student-card .student-name{font-size:18px;font-weight:950;line-height:1.2;word-break:break-all}.student-status{font-size:13px;font-weight:900;display:inline-flex;align-items:center;gap:5px}.student-card.missing .student-status{color:#8d9fba}.student-card.submitted{background:#e7f9f0;border-color:#75d6b0;color:#157e60}.student-card.submitted .student-status{color:#178967}.student-card.review{background:#fff3dc;border-color:#efc471;color:#8b5b1d}.student-card.review .student-status{color:#a56c18}.student-card.pop{animation:submit-pop .35s cubic-bezier(.17,.8,.2,1.2)}.student-card:disabled{opacity:.65;cursor:default}.group-card-empty{padding:15px;border:1px dashed var(--line);border-radius:15px;color:var(--muted);font-weight:700}.legend{display:flex;align-items:center;justify-content:center;gap:24px;color:#7086a1;font-size:14px;font-weight:800;padding:27px 0}.legend>span{display:flex;align-items:center;gap:7px}.legend-mark{display:inline-block;height:13px;width:13px;border-radius:50%}.submitted-mark{background:#36c49d}.missing-mark{background:#becbdc}.review-mark{background:#edaf42}.empty-student{background:#fff;border:1px dashed #c7d9f0;border-radius:24px;padding:45px 25px;text-align:center;color:#67809e;font-weight:800;font-size:17px}.empty-student strong{display:block;font-size:25px;color:#315b92;margin-bottom:8px}
.teacher-layout{max-width:1310px}.teacher-heading{align-items:center}.teacher-tabs{display:flex;gap:8px;border-bottom:1px solid #d7e5f4;margin-bottom:23px;overflow:auto}.teacher-tabs button{background:transparent;border:0;border-bottom:3px solid transparent;padding:13px 18px;color:#7488a2;font-size:16px;font-weight:900;white-space:nowrap}.teacher-tabs button.active{color:var(--blue);border-color:var(--blue)}.admin-grid{display:grid;grid-template-columns:300px minmax(0,1fr);gap:20px}.panel{background:#fff;border:1px solid #dce8f6;border-radius:23px;padding:24px;box-shadow:var(--shadow);min-width:0;margin-bottom:20px}.panel h2{font-size:22px;margin:0 0 17px;line-height:1.3}.panel h3{font-size:17px;margin:0 0 12px}.panel p{color:#6e839f;line-height:1.55}.panel-head{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:16px}.panel-head h2{margin:0}.panel-actions{display:flex;gap:8px;flex-wrap:wrap}.form-row{display:flex;gap:10px;flex-wrap:wrap;align-items:end}.form-row>*{flex:1;min-width:135px}.field{display:flex;flex-direction:column;gap:6px;font-size:14px;font-weight:800;color:#5f7795}.field input,.field select,.field textarea{min-height:45px;border:1.5px solid #d9e6f6;border-radius:12px;padding:10px 12px;color:#244267;background:#fbfdff;font-size:16px;outline:none}.field input:focus,.field select:focus{border-color:#73a7ef}.primary-button{border:0;border-radius:13px;background:var(--blue);color:white;font-weight:900;min-height:46px;padding:10px 19px;box-shadow:0 5px 0 #aac7f2;transition:transform .18s,background .18s}.primary-button:hover{background:var(--blue-dark);transform:translateY(-2px)}.primary-button:active{transform:translateY(3px);box-shadow:0 2px 0 #aac7f2}.secondary-button{min-height:44px}.danger-button{border:1px solid #efd0d3;color:#b44650;background:#fff6f6;border-radius:12px;padding:10px 15px;font-weight:850}.small-button{font-size:14px;padding:7px 11px;min-height:36px;border-radius:10px}.text-button{border:0;background:none;color:#3272d4;font-weight:850;padding:8px}.list-button{width:100%;text-align:left;display:flex;justify-content:space-between;align-items:center;gap:8px;border:1px solid #e1ebf7;background:#f9fbff;border-radius:13px;padding:12px 14px;margin-bottom:8px;color:#355274;font-weight:850}.list-button.selected{border-color:#83aceb;background:#eaf3ff;color:#1f64d6}.list-button small{color:#8ca0b9;font-size:12px}.status-pill{display:inline-flex;align-items:center;gap:5px;border-radius:99px;padding:5px 9px;font-size:13px;font-weight:900;white-space:nowrap}.status-pill.submitted{background:#e3f8ec;color:#178863}.status-pill.missing{background:#eef2f8;color:#68809d}.status-pill.review{background:#fff1d4;color:#a87021}.status-pill.completed{background:#e8f0ff;color:#2b69cf}.data-table{width:100%;border-collapse:collapse;font-size:15px}.data-table th{text-align:left;color:#6c819e;font-size:13px;font-weight:900;background:#f5f9fe}.data-table th,.data-table td{padding:12px 10px;border-bottom:1px solid #eaf0f7}.data-table td{font-weight:750}.data-table tr:last-child td{border-bottom:0}.table-wrap{overflow:auto;border:1px solid #edf2f8;border-radius:13px}.table-wrap .data-table{min-width:560px}.table-select{border:1px solid #d7e3f3;border-radius:9px;background:white;color:#315172;padding:6px 8px;max-width:170px}.empty-panel{border:1px dashed #cadcf0;border-radius:15px;padding:25px;text-align:center;color:#7389a5;font-weight:750}.hint{font-size:14px!important;color:#7e91a8!important}.subhead{display:flex;align-items:center;justify-content:space-between;gap:10px;margin-bottom:15px}.subhead h3{margin:0}.archive-stats{display:flex;gap:10px;flex-wrap:wrap;margin-bottom:14px}.archive-stats span{padding:8px 12px;background:#f4f8fd;border-radius:10px;color:#506d8e;font-size:14px;font-weight:800}
.auth-screen{min-height:calc(100vh - 82px);display:grid;place-items:center;padding:36px 20px;position:relative;z-index:2}.auth-card{background:#fff;border:1px solid #e0eaf7;border-radius:30px;box-shadow:0 18px 55px #24529419;padding:38px;max-width:480px;width:100%;text-align:center}.auth-symbol{width:74px;height:74px;border-radius:25px;background:#276be8;color:#fff;display:grid;place-items:center;margin:0 auto 20px;font-size:51px;transform:rotate(-8deg);box-shadow:0 7px 0 #b7cff4;animation:bob 3.2s ease-in-out infinite}.auth-card h1{font-size:27px;margin:0 0 10px}.auth-card>p:not(.eyebrow):not(.form-error){line-height:1.6;color:#6d829e;margin:0 0 20px}.auth-card form{text-align:left;display:grid;gap:15px}.auth-card label{display:grid;gap:7px;font-size:14px;font-weight:900;color:#587291}.auth-card input{height:50px;padding:10px 14px;border:1.5px solid #d8e5f6;border-radius:13px;background:#fbfdff;font-size:17px}.auth-card .primary-button{margin-top:3px}.form-error{color:#bf3c4d;font-weight:800;min-height:22px;margin:12px 0 0}.toast{position:fixed;left:50%;bottom:25px;transform:translateX(-50%);background:#1b385f;color:#fff;font-weight:850;padding:12px 19px;border-radius:13px;box-shadow:0 8px 25px #18355e38;z-index:20;max-width:min(90vw,540px);text-align:center}.celebration{position:fixed;inset:0;pointer-events:none;z-index:30;overflow:hidden}.confetti{position:absolute;width:9px;height:14px;border-radius:3px;animation:confetti-fall .85s ease-out forwards}
@keyframes bob{50%{transform:translateY(-5px) rotate(5deg)}}@keyframes twinkle{50%{opacity:.25;transform:scale(.7) rotate(25deg)}}@keyframes pulse{50%{opacity:.35}}@keyframes submit-pop{50%{transform:scale(1.055)}}@keyframes confetti-fall{to{transform:translate(var(--dx),var(--dy)) rotate(var(--rot));opacity:0}}
@media(max-width:1160px){.group-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.progress-card{grid-template-columns:1fr 1fr}.progress-hint{display:none}}@media(max-width:850px){.admin-grid{grid-template-columns:1fr}.teacher-layout{padding-top:25px}.teacher-heading h1{font-size:28px}}@media(max-width:690px){.topbar{padding:0 17px;height:72px}.brand{font-size:20px}.brand-icon{width:40px;height:40px}.connection{display:none}.teacher-toggle{padding:9px 11px}.teacher-toggle span:last-child{display:none}.workspace,.teacher-layout{padding:25px 17px}.page-head{align-items:stretch;flex-direction:column}.select-label select{width:100%}.assignment-date{margin-left:0;width:100%}.progress-card{display:block;padding:20px}.progress-copy{flex-wrap:wrap;margin-bottom:17px}.progress-bar{width:100%}.group-grid{grid-template-columns:1fr}.group-card{padding:20px}.legend{gap:15px;font-size:13px}.teacher-heading{align-items:start}.auth-screen{min-height:calc(100vh - 72px)}.auth-card{padding:28px 22px}.form-row{flex-direction:column;align-items:stretch}.form-row>*{width:100%}.panel{padding:19px}}@media(prefers-reduced-motion:reduce){*,*:before,*:after{animation-duration:.01ms!important;transition-duration:.01ms!important}}