:root {
  --primary: #1677ff;
  --primary-dark: #0958d9;
  --navy: #10233f;
  --text: #1c2738;
  --muted: #6d7889;
  --line: #e8edf4;
  --soft: #f5f8fc;
  --white: #fff;
  --green: #22a06b;
  --red: #e5484d;
  --shadow: 0 14px 40px rgba(36, 62, 99, .09);
  --radius: 16px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; color: var(--text); background: var(--white); font-family: "Microsoft YaHei", "PingFang SC", Arial, sans-serif; -webkit-font-smoothing: antialiased; }
a { color: inherit; text-decoration: none; }
button, select { font: inherit; }
button { cursor: pointer; }
.container { width: min(1180px, calc(100% - 40px)); margin: 0 auto; }
.hidden { display: none !important; }

.site-header { height: 72px; border-bottom: 1px solid rgba(226, 233, 242, .9); background: rgba(255, 255, 255, .94); position: sticky; top: 0; z-index: 20; backdrop-filter: blur(12px); }
.nav-wrap { height: 100%; display: flex; align-items: center; gap: 42px; }
.brand { display: inline-flex; align-items: center; gap: 10px; flex: none; }
.brand-mark { width: 38px; height: 38px; display: grid; place-items: center; border-radius: 11px; color: #fff; background: linear-gradient(145deg, #2f8dff, #0c64e5); font-size: 22px; font-weight: 900; box-shadow: 0 8px 16px rgba(22, 119, 255, .25); }
.brand strong, .brand small { display: block; }
.brand strong { font-size: 17px; letter-spacing: 1px; }
.brand small { margin-top: 1px; color: #8792a2; font-size: 8px; letter-spacing: 1.4px; }
.main-nav { height: 100%; display: flex; align-items: center; gap: 34px; margin-right: auto; }
.main-nav a { height: 100%; display: flex; align-items: center; color: #4c586a; font-size: 15px; position: relative; }
.main-nav a:hover, .main-nav a.active { color: var(--primary); }
.main-nav a.active::after { content: ""; height: 3px; border-radius: 2px 2px 0 0; background: var(--primary); position: absolute; left: 2px; right: 2px; bottom: 0; }
.header-action { padding: 10px 19px; border-radius: 9px; color: #fff; background: var(--primary); font-size: 14px; font-weight: 700; }
.nav-toggle { display: none; margin-left: auto; border: 0; background: transparent; font-size: 22px; }

.hero { min-height: 570px; overflow: hidden; background: radial-gradient(circle at 85% 20%, rgba(60, 145, 255, .17), transparent 29%), linear-gradient(135deg, #f8fbff 0%, #edf5ff 100%); position: relative; }
.hero::before, .hero::after { content: ""; position: absolute; border: 1px solid rgba(60, 145, 255, .08); border-radius: 50%; }
.hero::before { width: 500px; height: 500px; right: -170px; top: -160px; }
.hero::after { width: 260px; height: 260px; left: -130px; bottom: -160px; }
.hero-grid { min-height: 570px; display: grid; grid-template-columns: 1.08fr .92fr; align-items: center; gap: 80px; }
.eyebrow { display: inline-block; color: var(--primary); font-size: 12px; font-weight: 800; letter-spacing: 1.8px; }
.hero-copy h1 { margin: 14px 0 22px; color: #14233a; font-size: clamp(34px, 4.3vw, 52px); line-height: 1.17; letter-spacing: -2px; }
.hero-copy h1 span { display: block; white-space: nowrap; }
.hero-copy h1 em { width: max-content; display: block; color: var(--primary); font-style: normal; position: relative; }
.hero-copy h1 em::after { content: ""; height: 7px; background: rgba(22, 119, 255, .16); position: absolute; left: 2px; right: 2px; bottom: 5px; }
.hero-copy > p { max-width: 600px; margin: 0 0 30px; color: #657186; font-size: 17px; line-height: 1.9; }
.hero-actions { display: flex; gap: 13px; }
.button { min-height: 44px; padding: 11px 22px; border: 1px solid transparent; border-radius: 9px; display: inline-flex; align-items: center; justify-content: center; font-weight: 700; transition: .2s ease; }
.button:hover { transform: translateY(-1px); }
.button-primary { color: #fff; background: var(--primary); box-shadow: 0 8px 18px rgba(22, 119, 255, .18); }
.button-primary:hover { background: var(--primary-dark); }
.button-light { color: #39465a; border-color: #dce4ee; background: #fff; }
.button-light:hover { border-color: #9dc3f5; color: var(--primary); }
.button:disabled { cursor: not-allowed; opacity: .42; transform: none; }
.button-block { width: 100%; }
.button-small { min-height: 38px; padding: 8px 14px; font-size: 13px; }
.hero-stats { display: flex; gap: 38px; margin-top: 42px; }
.hero-stats div { padding-right: 36px; border-right: 1px solid #d9e4f1; }
.hero-stats div:last-child { border: 0; padding: 0; }
.hero-stats strong, .hero-stats span { display: block; }
.hero-stats strong { color: #1b375e; font-size: 24px; }
.hero-stats span { margin-top: 4px; color: #8190a4; font-size: 12px; }
.hero-visual { min-height: 390px; position: relative; }
.code-window { width: 100%; margin-top: 25px; overflow: hidden; border: 1px solid rgba(255,255,255,.12); border-radius: 17px; background: #11243f; box-shadow: 0 30px 60px rgba(25, 61, 105, .22); transform: rotate(1.5deg); }
.window-bar { height: 47px; padding: 0 16px; display: flex; align-items: center; gap: 7px; color: #7f92aa; border-bottom: 1px solid rgba(255,255,255,.08); background: #0b1d34; font-size: 11px; }
.window-bar i { width: 9px; height: 9px; border-radius: 50%; background: #ff6b68; }
.window-bar i:nth-child(2) { background: #ffc85b; }.window-bar i:nth-child(3) { background: #5ad18d; }.window-bar span { margin-left: 10px; }
.code-window pre { margin: 0; padding: 35px 34px 46px; color: #d3deed; font: 15px/2.05 Consolas, monospace; }
.code-window code b { color: #79b8ff; }.code-window code span { color: #9de7b6; }.code-window code mark { padding: 1px 5px; color: #ffc766; background: rgba(255, 199, 102, .08); }
.float-card { position: absolute; padding: 14px 18px; border: 1px solid rgba(255,255,255,.7); border-radius: 12px; background: rgba(255,255,255,.95); box-shadow: var(--shadow); }
.float-card-done { right: -20px; top: 4px; color: var(--green); font-size: 13px; font-weight: 700; }

.notice-section { border-bottom: 1px solid var(--line); }.notice { min-height: 58px; display: flex; align-items: center; gap: 16px; }.notice > span { padding: 4px 9px; color: #fff; border-radius: 4px; background: #ff8a34; font-size: 11px; }.notice p { margin: 0 auto 0 0; color: #586579; font-size: 13px; }.notice time { color: #a0a9b7; font-size: 12px; }
.section { padding: 78px 0; }.section-soft { background: var(--soft); }.section-heading { margin-bottom: 38px; display: flex; align-items: flex-end; justify-content: space-between; gap: 30px; }.section-heading.compact { align-items: center; }.section-heading h2 { margin: 9px 0 0; font-size: 31px; }.section-heading > p { max-width: 450px; margin: 0; color: var(--muted); font-size: 14px; line-height: 1.8; }.text-link { color: var(--primary); font-size: 14px; font-weight: 700; }
.level-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 17px; }.level-card { min-height: 176px; padding: 25px 21px; display: flex; gap: 15px; border: 1px solid var(--line); border-radius: 14px; background: #fff; box-shadow: 0 5px 18px rgba(30, 55, 85, .04); position: relative; transition: .22s ease; }.level-card:hover { border-color: #b7d6ff; box-shadow: var(--shadow); transform: translateY(-3px); }.level-number { width: 45px; height: 45px; flex: none; display: grid; place-items: center; border-radius: 12px; color: #fff; background: var(--level-color); font-size: 20px; font-weight: 800; }.level-card small { color: var(--level-color); font-size: 9px; font-weight: 800; letter-spacing: 1px; }.level-card h3 { margin: 5px 0 9px; font-size: 17px; }.level-card p { margin: 0; color: #7a8697; font-size: 12px; line-height: 1.7; }.level-card > b { position: absolute; right: 17px; bottom: 14px; color: #a9b3c0; }.level-blue { --level-color:#1677ff }.level-cyan { --level-color:#13a8a8 }.level-green { --level-color:#22a06b }.level-yellow { --level-color:#d8a106 }.level-orange { --level-color:#ef7b2d }.level-red { --level-color:#df4b55 }.level-purple { --level-color:#7656d6 }.level-navy { --level-color:#253b62 }
.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }.feature-card { padding: 28px; display: flex; align-items: center; gap: 18px; border-radius: var(--radius); background: #fff; box-shadow: 0 8px 30px rgba(40, 64, 94, .06); }.feature-card:hover { box-shadow: var(--shadow); }.feature-icon { width: 52px; height: 52px; flex: none; display: grid; place-items: center; border-radius: 14px; font-weight: 900; }.feature-card div { flex: 1; }.feature-card h3 { margin: 0 0 7px; font-size: 17px; }.feature-card p { margin: 0; color: var(--muted); font-size: 12px; }.feature-card > b { color: #a9b2c0; }.feature-blue .feature-icon { color: #1677ff; background:#eaf3ff }.feature-orange .feature-icon { color:#ed7a27; background:#fff1e7 }.feature-green .feature-icon { color:#1d9b67; background:#e8f8f0 }
.site-footer { padding-top: 55px; color: #aeb9c9; background: #10213a; }.footer-grid { padding-bottom: 42px; display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 70px; }.brand-footer { color: #fff; }.footer-grid p { max-width: 300px; color: #8290a5; font-size: 12px; line-height: 1.8; }.footer-grid h4 { margin: 0 0 18px; color: #fff; font-size: 14px; }.footer-grid > div > a:not(.brand) { margin: 0 0 11px; display: block; font-size: 12px; }.qr-placeholder { text-align: center; }.qr-placeholder div { width: 82px; height: 82px; margin-bottom: 7px; display: grid; place-items: center; color: #637289; border-radius: 6px; background: #fff; font-size: 12px; }.qr-placeholder span { font-size: 11px; }.copyright { padding: 19px 0; border-top: 1px solid rgba(255,255,255,.08); color: #687890; font-size: 11px; text-align: center; }.simple-footer { margin-top: 40px; padding-top: 0; }

.page-hero { padding: 36px 0; color: #fff; background: linear-gradient(125deg, #102d55, #165ca5); }.page-hero .container { display: flex; align-items: center; justify-content: space-between; }.page-hero .eyebrow { color: #91c4ff; }.page-hero h1 { margin: 7px 0 10px; font-size: 34px; }.page-hero p { margin: 0; color: #c6d9ee; font-size: 14px; }.page-hero-badge { min-width: 112px; padding: 13px 21px; border: 1px solid rgba(255,255,255,.16); border-radius: 12px; background: rgba(255,255,255,.08); text-align: center; }.page-hero-badge b, .page-hero-badge span { display: block; }.page-hero-badge b { font-size: 27px; }.page-hero-badge span { margin-top: 2px; color: #c5d8ed; font-size: 11px; }
.papers-section { min-height: 620px; background: #f7f9fc; }.filter-panel { padding: 6px 25px; border: 1px solid var(--line); border-radius: 13px; background: #fff; }.filter-row { min-height: 65px; display: flex; align-items: center; gap: 34px; border-bottom: 1px solid #edf0f5; }.filter-row:last-child { border: 0; }.filter-row > strong { width: 70px; flex: none; font-size: 13px; }.filter-options { display: flex; flex-wrap: wrap; gap: 8px; }.filter-chip { padding: 7px 14px; color: #657184; border: 0; border-radius: 6px; background: transparent; font-size: 12px; }.filter-chip:hover { color: var(--primary); }.filter-chip.active { color: #fff; background: var(--primary); }.list-toolbar { margin: 34px 0 17px; display: flex; align-items: center; justify-content: space-between; }.list-toolbar h2 { margin: 0; display: inline; font-size: 20px; }.list-toolbar span { margin-left: 12px; color: #939dac; font-size: 12px; }.list-toolbar select { padding: 9px 30px 9px 12px; color: #627085; border: 1px solid #dce3ec; border-radius: 7px; background: #fff; font-size: 12px; }.paper-list { display: grid; gap: 13px; }.paper-card { padding: 24px 26px; display: flex; align-items: center; gap: 22px; border: 1px solid var(--line); border-radius: 13px; background: #fff; transition: .2s ease; }.paper-card:hover { border-color: #b9d6fb; box-shadow: 0 10px 28px rgba(33, 67, 108, .07); }.paper-level { width: 58px; height: 58px; flex: none; display: grid; place-items: center; align-content: center; color: var(--primary); border-radius: 12px; background: #edf5ff; font-size: 24px; font-weight: 900; line-height: 1; }.paper-level small { margin-top: 3px; font-size: 10px; }.paper-info { flex: 1; min-width: 0; }.paper-tags { display: flex; gap: 6px; }.paper-tags span, .paper-tags i { padding: 3px 7px; border-radius: 4px; font-size: 10px; font-style: normal; }.paper-tags span { color: #fff; background: var(--primary); }.paper-tags i { color: #718096; background: #f0f3f7; }.paper-card h3 { margin: 10px 0; font-size: 17px; }.paper-card p { margin: 0; display: flex; flex-wrap: wrap; gap: 22px; color: #8994a3; font-size: 11px; }.mini-progress { width: 180px; height: 3px; margin-top: 11px; overflow: hidden; border-radius: 3px; background: #e9edf2; }.mini-progress i { height: 100%; display: block; background: var(--primary); }.progress-label { color: #94a0b0; font-size: 10px; }.empty-state { padding: 70px 20px; text-align: center; }.empty-state > span { width: 58px; height: 58px; margin: 0 auto 15px; display: grid; place-items: center; color: var(--primary); border-radius: 50%; background: #eaf3ff; font-size: 26px; }.empty-state h3 { margin: 0 0 9px; }.empty-state p { margin: 0 0 20px; color: var(--muted); font-size: 13px; }
.paper-actions { display: flex; flex-direction: column; align-items: center; gap: 7px; }.restart-paper { padding: 0; color: #9b8d82; border: 0; background: transparent; font-size: 11px; line-height: 1.4; }.restart-paper:hover { color: var(--primary); }

.exam-body { min-height: 100vh; background: #f4f7fb; }.exam-header { height: 68px; padding: 0 28px; display: grid; grid-template-columns: 1fr auto 1fr; align-items: center; border-bottom: 1px solid var(--line); background: #fff; }.exam-title { text-align: center; }.exam-title strong, .exam-title span { display: block; }.exam-title strong { font-size: 15px; }.exam-title span { margin-top: 4px; color: #929dad; font-size: 10px; }.exam-timer { justify-self: end; color: #7b8797; font-size: 12px; }.exam-timer b { margin-left: 7px; color: var(--primary); font: 18px Consolas, monospace; }.exam-layout { width: min(1180px, calc(100% - 40px)); margin: 34px auto; display: grid; grid-template-columns: 1fr 285px; gap: 22px; }.exam-main { min-width: 0; }.exam-progress { margin-bottom: 12px; display: flex; align-items: center; gap: 16px; color: #778397; font-size: 11px; }.exam-progress > div { height: 5px; flex: 1; overflow: hidden; border-radius: 5px; background: #e3e9f1; }.exam-progress i { height: 100%; display: block; border-radius: 5px; background: var(--primary); transition: width .25s; }.question-card { min-height: 460px; padding: 35px 42px; border: 1px solid var(--line); border-radius: var(--radius); background: #fff; box-shadow: 0 8px 28px rgba(37, 59, 90, .05); }.question-top { display: flex; align-items: center; justify-content: space-between; }.question-top span { color: var(--primary); font-size: 12px; font-weight: 700; }.question-top i { padding: 5px 9px; color: #718094; border-radius: 5px; background: #f2f5f8; font-size: 10px; font-style: normal; }.question-card h1 { margin: 26px 0 27px; font-size: 21px; line-height: 1.65; }.option-list { display: grid; gap: 12px; }.option { width: 100%; min-height: 57px; padding: 10px 16px; display: flex; align-items: center; gap: 15px; color: #445065; border: 1px solid #e1e7ef; border-radius: 9px; background: #fff; text-align: left; transition: .17s; }.option:hover { border-color: #8ebcf7; background: #f9fbff; }.option > b { width: 30px; height: 30px; display: grid; place-items: center; color: #7b8798; border-radius: 50%; background: #f0f3f7; font-size: 12px; }.option > span { flex: 1; }.option > i { width: 16px; height: 16px; border: 1px solid #cdd5e1; border-radius: 50%; }.option.selected { color: var(--primary); border-color: var(--primary); background: #f2f7ff; }.option.selected > b { color: #fff; background: var(--primary); }.option.selected > i { border: 5px solid var(--primary); }.option.correct { color: #168455; border-color: #57ba8a; background: #f0fbf5; }.option.correct > b { background: var(--green); }.option.wrong { color: var(--red); border-color: #ee8b8f; background: #fff5f5; }.option.wrong > b { background: var(--red); }.explanation { margin-top: 20px; padding: 15px 17px; border-left: 4px solid; border-radius: 6px; background: #f5f7fa; }.explanation p { margin: 7px 0 0; color: #606e81; font-size: 12px; line-height: 1.7; }.explanation-correct { border-color: var(--green); }.explanation-correct strong { color: var(--green); }.explanation-wrong { border-color: var(--red); }.explanation-wrong strong { color: var(--red); }.exam-nav { margin-top: 15px; display: flex; justify-content: space-between; }.answer-sheet { align-self: start; padding: 24px; border: 1px solid var(--line); border-radius: var(--radius); background: #fff; position: sticky; top: 20px; }.answer-sheet h2 { margin: 0 0 13px; font-size: 17px; }.answer-legend { display: flex; gap: 12px; color: #8a95a4; font-size: 9px; }.answer-legend span { display: flex; align-items: center; gap: 4px; }.answer-legend i { width: 7px; height: 7px; border: 1px solid #d5dce5; border-radius: 2px; }.answer-legend i.done { border-color: var(--primary); background: var(--primary); }.answer-legend i.current { border-color: var(--primary); background: #eaf3ff; }.answer-grid { margin: 20px 0 27px; display: grid; grid-template-columns: repeat(5, 1fr); gap: 8px; }.answer-grid button { aspect-ratio: 1; color: #718094; border: 1px solid #dfe5ed; border-radius: 6px; background: #fff; font-size: 11px; }.answer-grid button.done { color: #fff; border-color: var(--primary); background: var(--primary); }.answer-grid button.current { color: var(--primary); outline: 2px solid #afd1ff; outline-offset: 1px; }.answer-grid button.wrong { color: #fff; border-color: var(--red); background: var(--red); }.back-link { margin-top: 15px; display: block; color: #8d98a7; font-size: 11px; text-align: center; }.modal-backdrop { position: fixed; inset: 0; z-index: 50; display: grid; place-items: center; background: rgba(9, 22, 40, .55); backdrop-filter: blur(4px); }.result-modal { width: min(460px, calc(100% - 30px)); padding: 34px; border-radius: 18px; background: #fff; box-shadow: 0 25px 70px rgba(0,0,0,.22); text-align: center; position: relative; }.modal-close { position: absolute; top: 13px; right: 15px; color: #8a95a4; border: 0; background: transparent; font-size: 26px; }.result-ring { width: 105px; height: 105px; margin: 0 auto 18px; display: grid; place-items: center; align-content: center; color: var(--primary); border: 8px solid #e5f0ff; border-radius: 50%; }.result-ring b { font-size: 36px; line-height: 1; }.result-ring small { margin-top: 4px; font-size: 11px; }.result-modal h2 { margin: 0 0 8px; }.result-modal > p { margin: 0; color: var(--muted); font-size: 12px; }.result-stats { margin: 25px 0; display: grid; grid-template-columns: repeat(3, 1fr); border: 1px solid var(--line); border-radius: 10px; }.result-stats div { padding: 14px; border-right: 1px solid var(--line); }.result-stats div:last-child { border: 0; }.result-stats b, .result-stats span { display: block; }.result-stats b { font-size: 20px; }.result-stats span { margin-top: 3px; color: #8b96a5; font-size: 10px; }.result-actions { display: flex; gap: 10px; }.result-actions > * { flex: 1; }

.mistake-hero { background: linear-gradient(125deg, #3d315f, #674fa4); }.mistake-toolbar { margin-bottom: 20px; display: flex; align-items: center; justify-content: space-between; }.mistake-toolbar h2 { margin: 0; font-size: 21px; }.mistake-list { display: grid; gap: 15px; }.mistake-card { padding: 25px; display: grid; grid-template-columns: 42px 1fr auto; gap: 20px; border: 1px solid var(--line); border-radius: 13px; background: #fff; box-shadow: 0 5px 20px rgba(32, 52, 80, .04); }.mistake-number { width: 38px; height: 38px; display: grid; place-items: center; color: var(--red); border-radius: 10px; background: #fff0f0; font-weight: 800; }.mistake-content small { color: #8a95a6; }.mistake-content h3 { margin: 9px 0 15px; font-size: 16px; }.mistake-content > p { margin: 5px 0; color: #677386; font-size: 12px; }.wrong-text { color: var(--red); }.correct-text { color: var(--green); }.mistake-explanation { margin-top: 16px; padding: 12px 14px; border-radius: 7px; background: #f5f7fa; font-size: 12px; line-height: 1.7; }.mistake-explanation strong { margin-right: 12px; color: #40506a; }.mistake-actions { min-width: 80px; display: flex; flex-direction: column; align-items: flex-end; gap: 13px; }.remove-mistake { padding: 6px 10px; color: #6e7a8d; border: 1px solid #dce3eb; border-radius: 6px; background: #fff; font-size: 11px; }

@media (max-width: 980px) {
  .level-grid { grid-template-columns: repeat(2, 1fr); }.hero-grid { grid-template-columns: 1fr 1fr; gap: 35px; }.float-card-done { right: -5px; }.exam-layout { grid-template-columns: 1fr 245px; }.footer-grid { gap: 35px; }
}
@media (max-width: 760px) {
  .container { width: min(100% - 28px, 1180px); }.site-header { height: 62px; }.nav-wrap { gap: 15px; }.nav-toggle { display: block; }.header-action { display: none; }.main-nav { height: auto; padding: 8px; display: none; position: absolute; top: 62px; left: 14px; right: 14px; border: 1px solid var(--line); border-radius: 10px; background: #fff; box-shadow: var(--shadow); }.main-nav.open { display: block; }.main-nav a { height: 42px; padding: 0 12px; }.main-nav a.active::after { display: none; }.hero { min-height: auto; }.hero-grid { min-height: auto; padding: 65px 0 50px; display: block; }.hero-copy h1 { font-size: 41px; }.hero-visual { display: none; }.hero-stats { gap: 20px; }.hero-stats div { padding-right: 20px; }.notice { padding: 12px 0; }.notice time { display: none; }.section { padding: 55px 0; }.section-heading { display: block; }.section-heading > p { margin-top: 13px; }.section-heading .text-link { display: inline-block; margin-top: 14px; }.level-grid, .feature-grid { grid-template-columns: 1fr; }.level-card { min-height: 145px; }.footer-grid { grid-template-columns: 1fr 1fr; }.footer-grid > div:first-child { grid-column: 1/-1; }.qr-placeholder { display: none; }.page-hero { padding: 32px 0; }.page-hero h1 { font-size: 29px; }.page-hero-badge { display: none; }.filter-row { padding: 15px 0; display: block; }.filter-options { margin-top: 10px; }.paper-card { align-items: flex-start; flex-wrap: wrap; }.paper-card .button { margin-left: 80px; }.paper-card p { gap: 10px 16px; }.exam-header { height: auto; min-height: 66px; padding: 10px 15px; grid-template-columns: 1fr auto; }.exam-header .brand span:last-child { display: none; }.exam-title { display: none; }.exam-layout { width: calc(100% - 24px); margin: 18px auto; display: flex; flex-direction: column; }.question-card { min-height: 430px; padding: 25px 20px; }.question-card h1 { font-size: 18px; }.answer-sheet { position: static; order: -1; }.answer-sheet h2, .answer-legend { display: none; }.answer-grid { margin: 0 0 18px; grid-template-columns: repeat(10, 1fr); gap: 5px; }.answer-sheet .button, .answer-sheet .back-link { display: none; }.exam-nav::after { content: "提交试卷"; min-height: 44px; padding: 11px 16px; display: grid; place-items: center; color: #fff; border-radius: 9px; background: var(--primary); font-size: 13px; font-weight: 700; }.mistake-card { grid-template-columns: 38px 1fr; }.mistake-actions { grid-column: 2; flex-direction: row; align-items: center; }.result-modal { padding: 30px 22px; }
}
@media (max-width: 440px) {
  .hero-actions { flex-direction: column; }.hero-actions .button { width: 100%; }.hero-stats { justify-content: space-between; }.hero-stats div { padding-right: 13px; }.hero-stats strong { font-size: 20px; }.paper-level { width: 49px; height: 49px; }.paper-card { gap: 14px; padding: 19px 16px; }.paper-card h3 { font-size: 15px; }.paper-card .button { width: 100%; margin: 0; }.answer-grid { grid-template-columns: repeat(5, 1fr); }.footer-grid { grid-template-columns: 1fr; }.footer-grid > div:first-child { grid-column: auto; }
}

@media (max-width: 760px) {
  .answer-sheet .button { display: flex; }
  .exam-nav::after { display: none; }
}

/* Orange brand theme */
:root {
  --primary: #f47b20;
  --primary-dark: #d95d08;
  --navy: #2d2926;
  --text: #2f2b28;
  --muted: #756d67;
  --line: #eee5dc;
  --soft: #fff8f1;
  --shadow: 0 16px 42px rgba(126, 72, 28, .11);
}

body { background: #fffdfb; }
.brand { gap: 12px; }
.brand-logo { width: auto; height: 42px; max-width: 150px; display: block; object-fit: contain; }
.brand-copy { padding-left: 11px; border-left: 1px solid #eadfd5; }
.brand-footer .brand-logo { padding: 4px 7px; border-radius: 8px; background: #fff; }
.brand-footer .brand-copy { border-color: rgba(255,255,255,.18); }
.site-header { border-bottom-color: #f1e7dd; background: rgba(255, 253, 250, .95); }
.header-action, .button-primary { background: linear-gradient(135deg, #ff933e, #ef6d13); box-shadow: 0 9px 20px rgba(244, 123, 32, .23); }
.button-primary:hover, .header-action:hover { background: linear-gradient(135deg, #f48632, #d95d08); }
.button-light { border-color: #e8d9cc; background: #fffdfb; }
.button-light:hover { border-color: #f3a66c; }
.hero { background: radial-gradient(circle at 84% 18%, rgba(255, 153, 68, .2), transparent 30%), linear-gradient(135deg, #fffdf9 0%, #fff1e3 100%); }
.hero::before, .hero::after { border-color: rgba(244, 123, 32, .11); }
.hero-copy h1 { color: #312a25; }
.hero-copy h1 em::after { background: rgba(244, 123, 32, .17); }
.hero-copy > p { color: #72675f; }
.hero-stats div { border-color: #ead9ca; }
.hero-stats strong { color: #4b3424; }
.code-window { background: #302923; border-color: rgba(255,255,255,.1); box-shadow: 0 30px 60px rgba(105, 55, 19, .2); }
.window-bar { background: #251f1b; }
.code-window code b { color: #ffad69; }
.code-window code mark { color: #ffc273; }
.float-card-done { color: #d96513; }
.float-card-done.is-empty { color: #9a8d83; }
.daily-card { width: 100%; margin-top: 12px; padding: 28px; border: 1px solid rgba(255,255,255,.8); border-radius: 22px; background: rgba(255,255,255,.94); box-shadow: 0 28px 65px rgba(105,55,19,.16); transform: rotate(1deg); }
.daily-card-head { display: flex; align-items: center; justify-content: space-between; }
.daily-card-head span { color: #e87522; font-size: 10px; font-weight: 800; letter-spacing: 1.5px; }
.daily-card-head h2 { margin: 4px 0 0; color: #372b23; font-size: 23px; }
.daily-card-head > b { padding: 7px 12px; color: #a56d43; border-radius: 999px; background: #fff0e3; font-size: 11px; }
.daily-card-head > b.is-done { color: #168455; background: #e9f8f0; }
.daily-goal { margin: 24px 0 14px; display: grid; grid-template-columns: 80px 1fr; align-items: center; gap: 18px; }
.daily-goal-ring { width: 80px; height: 80px; display: grid; place-content: center; border: 7px solid #ffe2cc; border-top-color: var(--primary); border-radius: 50%; text-align: center; }
.daily-goal-ring strong, .daily-goal-ring small { display: block; }
.daily-goal-ring strong { color: var(--primary); font-size: 25px; line-height: 1; }
.daily-goal-ring small { margin-top: 4px; color: #a38c7a; font-size: 9px; }
.daily-goal h3 { margin: 0 0 7px; color: #47382e; font-size: 16px; }
.daily-goal p { margin: 0; color: #958477; font-size: 11px; line-height: 1.6; }
.daily-progress { height: 7px; overflow: hidden; border-radius: 99px; background: #f3e8df; }
.daily-progress i { width: 0; height: 100%; display: block; border-radius: inherit; background: linear-gradient(90deg,#ff9a4c,#ef6d13); transition: width .4s ease; }
.daily-tasks { margin-top: 20px; display: grid; gap: 9px; }
.daily-tasks a { padding: 13px 14px; display: grid; grid-template-columns: 32px 1fr auto; align-items: center; gap: 12px; color: inherit; border: 1px solid #f0e4da; border-radius: 11px; background: #fffcf9; transition: .18s ease; }
.daily-tasks a:hover { border-color: #f3a66c; transform: translateX(3px); }
.daily-tasks a > span { width: 30px; height: 30px; display: grid; place-items: center; color: #e76c16; border-radius: 8px; background: #fff0e3; font-size: 10px; font-weight: 800; }
.daily-tasks strong, .daily-tasks small { display: block; }
.daily-tasks strong { color: #4d3b2f; font-size: 12px; }
.daily-tasks small { margin-top: 3px; color: #a08f82; font-size: 9px; }
.daily-tasks a > b { color: #e66d19; font-size: 10px; }
.daily-quote { margin: 17px 0 0; color: #9a887a; font-size: 10px; line-height: 1.6; text-align: center; }
.notice-section { background: #fffaf5; }
.notice > span { background: var(--primary); }
.level-card:hover, .paper-card:hover { border-color: #f2b789; box-shadow: var(--shadow); }
.level-blue, .level-cyan, .level-green, .level-yellow, .level-orange, .level-red, .level-purple, .level-navy { --level-color: #f47b20; }
.level-card:nth-child(even) { background: #fffcf8; }
.feature-blue .feature-icon, .feature-orange .feature-icon, .feature-green .feature-icon { color: #e56811; background: #fff0e3; }
.section-soft, .papers-section, .records-section { background: #fff8f1; }
.site-footer { background: #302923; }
.page-hero { background: radial-gradient(circle at 80% 20%, rgba(255,255,255,.13), transparent 25%), linear-gradient(125deg, #c95208, #f68631); }
.page-hero .eyebrow { color: #ffe0c5; }
.page-hero p, .page-hero-badge span { color: #fff0e3; }
.mistake-hero { background: linear-gradient(125deg, #9d3d08, #e66d19); }
.records-hero { background: linear-gradient(125deg, #b84908, #ff8a32); }
.filter-panel, .paper-card, .question-card, .answer-sheet, .mistake-card, .record-card { border-color: #eee2d7; }
.filter-row { border-color: #f2e8df; }
.paper-level, .empty-state > span { background: #fff0e3; }
.paper-tags i { background: #f7f0e9; }
.mini-progress, .exam-progress > div { background: #eee5dc; }
.option:hover { border-color: #f3a66c; background: #fffaf5; }
.option.selected { background: #fff4e9; }
.answer-grid button.current { outline-color: #ffc99e; }
.result-ring { border-color: #ffe5d0; }

.record-summary { margin: 25px 0 38px; display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
.record-summary article { padding: 24px; border: 1px solid #eee0d3; border-radius: 14px; background: #fff; box-shadow: 0 8px 26px rgba(122, 72, 34, .05); }
.record-summary span, .record-summary b, .record-summary small { display: block; }
.record-summary span { color: #7b6e64; font-size: 12px; }
.record-summary b { margin: 9px 0 5px; color: var(--primary); font-size: 31px; }
.record-summary small { color: #a0958b; font-size: 10px; }
.record-toolbar { margin-bottom: 17px; display: flex; align-items: center; justify-content: space-between; }
.record-toolbar h2 { margin: 0; display: inline; font-size: 21px; }
.record-toolbar span { margin-left: 12px; color: #9a8f86; font-size: 11px; }
.record-list { display: grid; gap: 13px; }
.record-card { padding: 21px 24px; display: grid; grid-template-columns: 42px 1fr 75px 92px; align-items: center; gap: 18px; border: 1px solid; border-radius: 13px; background: #fff; }
.record-rank { width: 38px; height: 38px; display: grid; place-items: center; color: var(--primary); border-radius: 10px; background: #fff0e3; font-weight: 800; }
.record-main small { color: #a0948b; font-size: 10px; }
.record-main h3 { margin: 7px 0 10px; font-size: 15px; }
.record-meta { display: flex; flex-wrap: wrap; gap: 17px; color: #7c7168; font-size: 11px; }
.record-score { text-align: center; }
.record-score b { color: #7f756d; font-size: 28px; }
.record-score span { margin-left: 2px; color: #9d938b; font-size: 10px; }
.record-score.is-good b { color: var(--primary); }
.record-actions { display: grid; gap: 8px; }
.record-actions .button { width: 100%; padding-inline: 10px; }
.record-detail { grid-column: 1 / -1; margin-top: 4px; padding-top: 18px; border-top: 1px solid #f1e6dc; }
.record-detail-list { display: grid; gap: 10px; }
.record-question { padding: 14px 16px; border: 1px solid #eee3d9; border-left: 4px solid #c9b9aa; border-radius: 10px; background: #fffdfb; }
.record-question.is-correct { border-left-color: var(--green); }
.record-question.is-wrong { border-left-color: var(--red); }
.record-question.is-unanswered { border-left-color: #b8aa9e; }
.record-question-top { margin-bottom: 9px; display: flex; align-items: center; justify-content: space-between; gap: 12px; }
.record-question-top b { font-size: 13px; }
.record-question-top span { padding: 3px 8px; border-radius: 999px; background: #f5eee8; color: #806f62; font-size: 11px; font-weight: 700; }
.record-question.is-correct .record-question-top span { color: #168455; background: #e9f8f0; }
.record-question.is-wrong .record-question-top span { color: var(--red); background: #fff0f0; }
.record-question-title { color: #40362f; font-size: 13px; line-height: 1.7; }
.record-question-title p { margin: 0 0 8px; }
.record-question-title img { max-width: 100%; height: auto; }
.record-question-answer { margin-top: 10px; display: grid; gap: 6px; color: #74675e; font-size: 12px; line-height: 1.6; }
.record-question-answer p { margin: 0; display: inline; }
.record-question-explanation { margin-top: 12px; padding: 12px 14px; border-radius: 8px; background: #fff6ee; color: #68584d; font-size: 12px; line-height: 1.75; }
.record-question-explanation strong { display: block; margin-bottom: 5px; color: #3f352e; font-size: 12px; }
.record-question-explanation p { margin: 0; }
.record-detail-empty { padding: 18px; color: #8b7b6e; border-radius: 10px; background: #fff8f1; font-size: 12px; text-align: center; }
.filter-options-scroll { max-height: 84px; overflow-y: auto; padding: 4px 0; }
.question-title { margin: 26px 0 27px; font-size: 18px; line-height: 1.75; }
.question-title p { margin: 0 0 12px; }
.question-title img, .option img { max-width: 100%; height: auto; }
.question-code { max-width: 100%; margin: 14px 0; padding: 16px 18px; overflow-x: auto; border: 1px solid #eadfd5; border-radius: 9px; background: #2f2925; color: #f9eee5; font: 15px/1.7 Consolas, Monaco, monospace; white-space: pre; }
.option span { min-width: 0; line-height: 1.65; }
.option span p { margin: 0; }
.knowledge-hero { background: radial-gradient(circle at 80% 20%, rgba(255,255,255,.15), transparent 25%), linear-gradient(125deg, #b84408, #fb8a36); }
.knowledge-setup { overflow: hidden; border: 1px solid #eee0d3; border-radius: 16px; background: #fff; box-shadow: 0 12px 35px rgba(122, 72, 34, .06); }
.knowledge-step { padding: 27px 30px; border-bottom: 1px solid #f2e8df; }
.knowledge-step-title { margin-bottom: 20px; display: flex; align-items: center; gap: 13px; }
.knowledge-step-title > b { width: 34px; height: 34px; flex: none; display: grid; place-items: center; color: #fff; border-radius: 10px; background: linear-gradient(135deg, #ff963f, #ef6d13); font-size: 14px; }
.knowledge-step-title h2 { margin: 0 0 4px; font-size: 18px; }
.knowledge-step-title p { margin: 0; color: #908274; font-size: 11px; }
.knowledge-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px; }
.knowledge-card { min-height: 88px; padding: 16px; display: grid; grid-template-columns: 1fr auto; align-items: center; gap: 5px 12px; color: #4f463f; border: 1px solid #eadfd5; border-radius: 11px; background: #fffdfa; text-align: left; transition: .18s ease; }
.knowledge-card:hover { border-color: #f3a66c; transform: translateY(-1px); box-shadow: 0 8px 18px rgba(190, 95, 24, .08); }
.knowledge-card span { font-size: 14px; font-weight: 700; }
.knowledge-card small { grid-column: 1; color: #9a8b7e; font-size: 10px; }
.knowledge-card i { grid-column: 2; grid-row: 1 / 3; color: #c4b3a5; font-style: normal; }
.knowledge-card.active { color: var(--primary-dark); border-color: var(--primary); background: #fff4e9; box-shadow: inset 0 0 0 1px var(--primary); }
.knowledge-card.active i { color: var(--primary); }
.practice-count-row { display: flex; align-items: center; justify-content: space-between; gap: 30px; }
.practice-count-row .knowledge-step-title { margin-bottom: 0; }
.knowledge-start { padding: 23px 30px; display: flex; align-items: center; justify-content: space-between; gap: 25px; background: #fff9f3; }
.knowledge-start strong, .knowledge-start span { display: block; }
.knowledge-start strong { margin-bottom: 6px; font-size: 15px; }
.knowledge-start span { color: #8f8074; font-size: 11px; }
.instant-tip { margin-top: 18px; padding: 12px 15px; color: #8d6d55; border-radius: 7px; background: #fff7ef; font-size: 11px; text-align: center; }
.option:disabled { cursor: default; opacity: 1; }
.option:disabled:hover { transform: none; }
.explanation { padding: 19px 21px; }
.explanation strong { font-size: 16px; }
.explanation p { margin-top: 9px; font-size: 15px; line-height: 1.85; }
.option span .question-code { margin: 6px 0; font-size: 14px; text-align: left; }
.programming-editor { margin-top: 24px; }
.programming-editor label { margin-bottom: 9px; display: block; color: #5e4d41; font-size: 13px; font-weight: 700; }
.programming-editor textarea { width: 100%; min-height: 280px; padding: 18px; resize: vertical; color: #f8eee6; border: 1px solid #463b34; border-radius: 10px; outline: none; background: #2f2925; font: 14px/1.75 Consolas, Monaco, monospace; tab-size: 4; }
.programming-editor textarea:focus { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(244,123,32,.12); }
.programming-editor textarea:disabled { color: #bbaea4; background: #39322d; }
.programming-reference { margin-top: 22px; padding: 18px 20px; border: 1px solid #f0d8c5; border-radius: 10px; background: #fff9f3; }
.programming-reference > strong { display: block; margin-bottom: 12px; color: #d9610d; font-size: 15px; }
.programming-reference p { margin: 7px 0; line-height: 1.75; }
.programming-reference pre { margin: 10px 0 0; }
.answer-grid button.programming { color: #8b5a35; border-style: dashed; background: #fff8f1; }
.answer-grid button.programming.done { color: #fff; border-style: solid; background: #d8752e; }

@media (max-width: 980px) {
  .main-nav { gap: 22px; }
  .record-summary { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 760px) {
  .hero-copy h1 { font-size: 34px; }
  .brand-logo { height: 34px; max-width: 118px; }
  .brand-copy { display: none; }
  .record-card { grid-template-columns: 38px 1fr 58px; padding: 18px 15px; gap: 11px; }
  .record-actions { grid-column: 2 / -1; grid-template-columns: 1fr 1fr; }
  .record-card .button { justify-self: stretch; }
  .record-toolbar span { display: none; }
  .knowledge-step { padding: 22px 18px; }
  .knowledge-grid { grid-template-columns: 1fr 1fr; }
  .practice-count-row, .knowledge-start { align-items: stretch; flex-direction: column; }
  .knowledge-start { padding: 20px 18px; }
  .knowledge-start .button { width: 100%; }
}

@media (max-width: 440px) {
  .knowledge-grid { grid-template-columns: 1fr; }
}
@media (max-width: 440px) {
  .record-summary { grid-template-columns: 1fr 1fr; gap: 10px; }
  .record-summary article { padding: 18px 15px; }
  .record-summary b { font-size: 25px; }
}

@media (max-width: 760px) {
  .paper-actions { width: 100%; align-items: stretch; }
  .paper-actions .button { width: 100%; margin: 0; }
  .restart-paper { text-align: center; }
}