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0;color:var(--muted);font-size:13px;line-height:1.5}@media(max-width:760px){.ss-header{min-height:66px;padding:10px 16px;gap:14px}.ss-brand img{width:105px}.ss-header nav{display:none}.ss-back{margin-left:auto;font-size:11px}.ss-shell{padding:30px 15px 56px}.ss-hero{min-height:0;padding:30px 22px 130px;border-radius:21px}.ss-hero h1{font-size:39px}.ss-hero>p{font-size:15px}.ss-device-note{left:20px;right:20px;bottom:20px;max-width:none}.ss-section-title{align-items:flex-start;flex-direction:column}.ss-topic-card{grid-template-columns:52px 1fr;gap:14px;padding:18px}.ss-topic-icon{width:52px;height:52px;border-radius:14px;font-size:22px}.ss-topic-action{grid-column:1/-1;width:100%}.ss-learning-layout{grid-template-columns:1fr}.ss-lesson-card{padding:24px 19px}.ss-tip{order:-1}.ss-question-card{padding:22px 17px}.ss-question{font-size:20px}.ss-choices{grid-template-columns:1fr}.ss-result-card{grid-template-columns:1fr;padding:25px 19px}.ss-result-ring{margin:auto;width:156px;height:156px}.ss-result-ring::before{width:119px;height:119px}.ss-result-actions{flex-direction:column}.ss-review{padding:21px 17px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}.ss-progress span{transition:none}}
.ss-mistake-book{margin-top:28px;padding:26px;border:1px solid #f1d7ab;border-radius:22px;background:linear-gradient(135deg,#fffaf0,#fff);box-shadow:0 10px 30px #7b4c1609}.ss-mistake-head{display:flex;align-items:center;justify-content:space-between;gap:16px}.ss-mistake-head h2{margin:5px 0 0;font-size:27px}.ss-mistake-count{padding:6px 11px;border-radius:99px;color:#9b5a09;background:#fff0d5;font-size:12px;font-weight:850}.ss-mistake-empty{margin:16px 0 0;color:#6e7890;line-height:1.55}.ss-mistake-list{display:grid;gap:9px;margin-top:16px}.ss-mistake-item{display:grid;grid-template-columns:42px 1fr auto;align-items:center;gap:12px;padding:13px;border:1px solid #f1dfc2;border-radius:13px;background:#fff}.ss-mistake-item>span:first-child{display:grid;place-items:center;width:38px;height:38px;border-radius:11px;color:#b4512e;background:#fff0e8;font-weight:900}.ss-mistake-item h3{margin:0;font-size:14px;line-height:1.4}.ss-mistake-item p{margin:4px 0 0;color:#7b6c62;font-size:11px}.ss-mistake-item>strong{color:#a65b16;font-size:11px}.ss-mistake-action{width:100%;min-height:49px;margin-top:16px;border:1px solid #e5bd7b;border-radius:12px;color:#8b510b;background:#fff8e8;font-weight:850}.ss-mistake-action:hover{background:#fff1d2}@media(max-width:760px){.ss-mistake-book{padding:20px 16px}.ss-mistake-item{grid-template-columns:38px 1fr}.ss-mistake-item>strong{grid-column:2}.ss-mistake-head h2{font-size:24px}}
/* 2026-10-25 — Tự học lấy câu từ thư viện LQS: chọn lớp → chương/bài/kỹ năng, làm bài ba loại câu, kết quả theo ô kiến thức. */
.ss-state{text-align:center;max-width:620px}.ss-state h1,.ss-state h2{margin:14px 0 8px;font-size:28px}.ss-state p{color:var(--muted);line-height:1.55}.ss-loader{display:inline-block;width:38px;height:38px;border-radius:50%;border:4px solid #dbe7f6;border-top-color:var(--blue);animation:ss-spin .9s linear infinite}@keyframes ss-spin{to{transform:rotate(360deg)}}.ss-link-button{display:inline-flex;align-items:center;justify-content:center;text-decoration:none;margin-top:10px}
.ss-grade-section{margin-bottom:34px}.ss-grade-chips{display:flex;flex-wrap:wrap;gap:10px}.ss-grade-chip{display:grid;gap:2px;min-width:92px;min-height:56px;padding:9px 14px;border:1px solid #cfe0f3;border-radius:14px;background:#fff;color:#143563;font-weight:850;text-align:left}.ss-grade-chip small{color:#6b7f9d;font-size:11px;font-weight:700}.ss-grade-chip[aria-pressed="true"]{border-color:var(--blue);background:#eaf2ff;color:#1457c7;box-shadow:0 0 0 3px #216bf21f}.ss-grade-chip.is-empty{opacity:.6}
.ss-chapter-list{display:grid;gap:12px}.ss-chapter{border:1px solid #d8e6f7;border-radius:20px;background:#fff;box-shadow:0 10px 30px #173f750b}.ss-chapter.is-empty{opacity:.62}.ss-chapter-summary{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:18px 22px;cursor:pointer;list-style:none}.ss-chapter-summary::-webkit-details-marker{display:none}.ss-chapter-summary::after{content:"▾";margin-left:8px;color:#7586a0;transition:transform .2s}.ss-chapter[open]>.ss-chapter-summary::after{transform:rotate(180deg)}.ss-chapter-copy{display:grid;gap:3px;min-width:0}.ss-chapter-copy h3{margin:0;font-size:19px;line-height:1.3}.ss-count{flex:none;padding:5px 10px;border-radius:99px;color:#1663d2;background:#eaf2ff;font-size:12px;font-weight:800;white-space:nowrap}.is-empty .ss-count{color:#7586a0;background:#eef2f7}
.ss-chapter-body{display:grid;gap:10px;padding:0 22px 20px;border-top:1px solid #edf3fa}.ss-node-row{display:flex;align-items:center;justify-content:space-between;gap:14px;padding:12px 0}.ss-node-row--chapter{border-bottom:1px dashed #dde8f5}.ss-node-label{font-weight:800;color:#355076}.ss-node-copy{display:flex;flex-wrap:wrap;align-items:center;gap:6px 10px;min-width:0}.ss-node-copy h4{margin:0;flex-basis:100%;font-size:16px;line-height:1.35}.ss-topic-block{padding:4px 0 8px;border-bottom:1px solid #edf3fa}.ss-topic-block:last-child{border-bottom:0}.ss-topic-block.is-empty{opacity:.65}
.ss-node-action{flex:none;min-height:42px;padding:9px 14px;border:0;border-radius:11px;color:#fff;background:linear-gradient(135deg,#3682ff,#2165e8);font-weight:800;font-size:13px;box-shadow:0 7px 16px #2168e824}.ss-node-action:disabled{color:#7586a0;background:#eef2f7;box-shadow:none;cursor:not-allowed}.ss-node-action--compact{min-height:36px;padding:7px 12px;font-size:12px;border-radius:9px}
.ss-skill-list{display:grid;gap:6px;margin:0;padding:0 0 6px 14px;list-style:none;border-left:2px solid #e3ecf7}.ss-skill-row{display:flex;align-items:center;justify-content:space-between;gap:12px;padding:6px 0}.ss-skill-row.is-empty{opacity:.65}.ss-skill-label{font-size:14px;color:#2a4569;line-height:1.4}
.ss-question-list{display:grid;gap:16px;margin:0;padding:0;list-style:none}.ss-question-card{padding:26px}.ss-question-head{display:flex;justify-content:space-between;gap:10px;margin-bottom:10px}.ss-question-number{color:#1763d5;font-size:12px;font-weight:850;letter-spacing:.08em}.ss-question-type{color:#7586a0;font-size:12px;font-weight:700}.ss-question-card .ss-question{margin:0 0 18px;font-size:19px}.ss-question-image{display:block;max-width:100%;height:auto;margin:0 0 16px;border-radius:12px;border:1px solid var(--line)}
.ss-choice.is-selected{border-color:var(--blue);background:#eaf2ff;box-shadow:0 0 0 3px #216bf21f}.ss-choice strong{font-weight:650}
.ss-tf-list{display:grid;gap:10px}.ss-tf-row{display:grid;grid-template-columns:minmax(0,1fr) auto;align-items:center;gap:12px;padding:12px 14px;border:1px solid #e1ebf7;border-radius:12px;background:#f9fbff}.ss-tf-text{line-height:1.5}.ss-tf-text b{color:#1763d5}.ss-tf-controls{display:flex;gap:6px}.ss-tf-button{min-width:64px;min-height:40px;padding:8px 12px;border:1px solid #cfe0f3;border-radius:10px;background:#fff;color:#143563;font-weight:800}.ss-tf-button.is-selected{border-color:var(--blue);background:#eaf2ff;color:#1457c7}
.ss-short-field{display:grid;gap:6px;font-size:13px;font-weight:750;color:#355076}.ss-short-field input{min-height:48px;padding:10px 14px;border:1px solid #cfe0f3;border-radius:12px;font:inherit;font-size:17px;color:#09275c;background:#fff}.ss-short-field input:focus{border-color:var(--blue)}
.ss-submit-note{margin:18px 0 10px;color:var(--muted);font-size:14px;line-height:1.5}.ss-submit{width:100%}.ss-practice form{display:block}
.ss-skill-result{margin-top:22px}.ss-review .ss-skill-result-row{display:block;padding:14px 0;border-top:1px solid #e3ebf5}.ss-skill-result-row:first-child{border-top:0}.ss-skill-result-head{display:flex;justify-content:space-between;gap:12px;align-items:baseline}.ss-skill-result-head h3{margin:0;font-size:15px}.ss-skill-result-head strong{color:#1763d5;white-space:nowrap}.ss-skill-result-row p{margin:6px 0 0;color:var(--muted);font-size:13px}.ss-meter{height:8px;margin-top:8px;border-radius:99px;background:#e3ebf5;overflow:hidden}.ss-meter span{display:block;height:100%;border-radius:inherit;background:linear-gradient(90deg,#2d7df5,#27c581)}
.ss-review-correct{color:#0a6f44!important}.ss-review-solution{white-space:pre-line}.ss-review h3 span,.ss-review p{overflow-wrap:anywhere}.ss-mistake-action--inline{width:auto;min-height:40px;margin:0;padding:8px 12px;font-size:12px}
.katex-display{overflow-x:auto;overflow-y:hidden;max-width:100%}.katex{font-size:1.05em}
@media(max-width:760px){.ss-chapter-summary{padding:15px 16px}.ss-chapter-body{padding:0 16px 16px}.ss-node-row{flex-wrap:wrap}.ss-node-row .ss-node-action{width:100%}.ss-skill-row{flex-wrap:wrap}.ss-skill-row .ss-node-action{width:100%}.ss-question-card{padding:18px 15px}.ss-tf-row{grid-template-columns:1fr}.ss-tf-controls{justify-content:stretch}.ss-tf-button{flex:1}.ss-mistake-item{grid-template-columns:38px 1fr}.ss-mistake-action--inline{grid-column:2;width:100%}}