@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+Thai:wght@400;500;600;700;800&display=swap');

:root {
  --bg: #eaf5ff;
  --bg-2: #dceeff;
  --card: rgba(255,255,255,.94);
  --text: #10213a;
  --muted: #65758d;
  --line: #d7e8f8;
  --primary: #3c91ef;
  --primary-2: #72b9fb;
  --primary-soft: #edf7ff;
  --danger: #ef5d68;
  --success: #1fa971;
  --warning: #f3a52b;
  --shadow: 0 20px 55px rgba(41,107,169,.13);
  --radius: 24px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; min-height: 100vh; font-family: "Noto Sans Thai", system-ui, sans-serif; color: var(--text); background: linear-gradient(135deg, #eef8ff 0%, #e3f2ff 45%, #f7fbff 100%); }
button, input, select { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
button:focus-visible, a:focus-visible { outline: 3px solid rgba(60,145,239,.28); outline-offset: 3px; }
.container { width: min(1080px, calc(100% - 28px)); margin: 0 auto; }
.sky-decor { position: fixed; z-index: -1; border-radius: 999px; background: rgba(137,198,250,.20); filter: blur(.2px); pointer-events: none; }
.sky-left { width: 280px; height: 280px; left: -150px; bottom: 30px; }
.sky-right { width: 360px; height: 170px; right: -130px; top: 150px; border-radius: 45% 45% 35% 35%; }

.btn { border: 0; border-radius: 15px; padding: 13px 20px; color: white; background: linear-gradient(135deg, var(--primary), var(--primary-2)); font-weight: 800; cursor: pointer; box-shadow: 0 10px 22px rgba(60,145,239,.18); transition: transform .18s ease, box-shadow .18s ease, opacity .18s; }
.btn:hover { transform: translateY(-1px); box-shadow: 0 14px 28px rgba(60,145,239,.24); }
.btn:disabled { opacity: .45; cursor: not-allowed; transform: none; }
.btn.ghost { color: var(--text); background: #fff; border: 1px solid var(--line); box-shadow: none; }
.btn.danger { background: linear-gradient(135deg, #ef5d68, #ff8b7f); }
.btn.compact { padding: 9px 13px; font-size: 13px; }
.btn.large { min-height: 54px; font-size: 16px; }
.eyebrow { display: inline-flex; align-items: center; gap: 6px; color: var(--primary); font-size: 12px; font-weight: 800; letter-spacing: .03em; }

.landing-page { padding: 30px 0 60px; }
.landing-container { max-width: 1020px; }
.site-brand { display: flex; align-items: center; gap: 12px; margin-bottom: 22px; }
.site-brand strong, .brand-inline strong { display: block; font-size: 22px; color: var(--primary); }
.site-brand span, .brand-inline span { display: block; color: var(--muted); font-size: 12px; }
.brand-mark { width: 54px; height: 54px; border-radius: 18px; display: grid; place-items: center; font-size: 27px; background: linear-gradient(145deg, #fff, #d8efff); box-shadow: 0 10px 22px rgba(53,136,210,.13); }
.brand-mark.small { width: 42px; height: 42px; border-radius: 14px; font-size: 20px; }
.hero-card { position: relative; overflow: hidden; display: grid; grid-template-columns: 1fr auto; gap: 30px; align-items: center; padding: 38px 42px; border-radius: 30px; color: white; background: linear-gradient(135deg, #3d91ec 0%, #70b7f8 75%); box-shadow: var(--shadow); }
.hero-card::after { content: ""; position: absolute; width: 260px; height: 260px; border-radius: 50%; right: -70px; top: -120px; background: rgba(255,255,255,.13); }
.hero-copy { position: relative; z-index: 1; }
.hero-copy .eyebrow { color: #fff; opacity: .9; }
.hero-copy h1 { margin: 8px 0 4px; font-size: clamp(36px, 6vw, 60px); line-height: 1.08; }
.hero-copy p { max-width: 700px; margin: 0; line-height: 1.8; opacity: .95; }
.hero-pills { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 20px; }
.hero-pills span { padding: 7px 12px; border: 1px solid rgba(255,255,255,.34); border-radius: 999px; background: rgba(255,255,255,.11); font-size: 12px; font-weight: 700; }
.hero-orb { position: relative; z-index: 1; width: 145px; height: 145px; border-radius: 50%; display: grid; place-content: center; text-align: center; background: rgba(255,255,255,.18); border: 1px solid rgba(255,255,255,.3); backdrop-filter: blur(10px); }
.hero-orb strong { font-size: 52px; line-height: 1; }
.hero-orb span { font-size: 14px; }
.setup-grid { display: grid; grid-template-columns: 1fr 280px; gap: 18px; margin-top: 20px; align-items: stretch; }
.setup-card, .info-card { border: 1px solid rgba(255,255,255,.8); background: var(--card); border-radius: var(--radius); padding: 24px; box-shadow: var(--shadow); backdrop-filter: blur(15px); }
.card-title-row { display: flex; justify-content: space-between; gap: 15px; align-items: start; }
.card-title-row h2 { margin: 4px 0 0; font-size: 22px; }
.live-dot { padding: 6px 10px; border-radius: 999px; background: #ebfbf5; color: var(--success); font-size: 11px; font-weight: 800; }
.subject-cards { display: grid; grid-template-columns: repeat(5, 1fr); gap: 10px; margin: 20px 0; }
.subject-card { min-height: 132px; display: flex; flex-direction: column; justify-content: space-between; padding: 15px; border-radius: 18px; background: #f8fbff; border: 1px solid var(--line); }
.subject-card > span { width: 28px; height: 28px; border-radius: 9px; display: grid; place-items: center; background: var(--primary-soft); color: var(--primary); font-weight: 800; }
.subject-card strong { font-size: 13px; line-height: 1.45; }
.subject-card b { color: var(--primary); font-size: 17px; }
.rules-box { padding: 15px 17px; border: 1px dashed #a8d4fa; border-radius: 17px; background: #f3f9ff; }
.rules-box p { margin: 6px 0 0; color: var(--muted); font-size: 13px; line-height: 1.7; }
.landing-actions { display: grid; grid-template-columns: 1fr 1.2fr; gap: 12px; margin-top: 18px; }
.info-card h3 { margin: 5px 0 8px; font-size: 22px; }
.info-card > p { color: var(--muted); line-height: 1.7; font-size: 13px; }
.info-stat { display: flex; gap: 12px; align-items: center; padding: 13px 0; border-top: 1px dashed var(--line); }
.info-stat strong { min-width: 45px; color: var(--primary); font-size: 24px; }
.info-stat span { color: var(--muted); font-size: 12px; }

.exam-shell { min-height: 100vh; padding-bottom: 95px; }
.exam-header { position: sticky; top: 0; z-index: 20; background: rgba(236,247,255,.88); border-bottom: 1px solid rgba(209,230,248,.85); backdrop-filter: blur(18px); }
.exam-header-inner { min-height: 74px; display: flex; justify-content: space-between; align-items: center; gap: 20px; }
.brand-inline { display: flex; align-items: center; gap: 10px; }
.brand-inline strong { font-size: 18px; }
.timer-panel { padding: 8px 14px; min-width: 145px; text-align: center; border-radius: 15px; background: #fff; border: 1px solid var(--line); box-shadow: 0 8px 20px rgba(38,116,181,.08); }
.timer-panel span { display: block; color: var(--muted); font-size: 10px; }
.timer-panel strong { display: block; color: var(--primary); font-size: 23px; letter-spacing: .04em; }
.timer-panel strong.warning { color: var(--warning); }
.timer-panel strong.danger { color: var(--danger); }
.exam-main { padding: 22px 0; }
.exam-container { max-width: 910px; }
.progress-card { border-radius: 22px; background: rgba(255,255,255,.94); border: 1px solid var(--line); padding: 15px 18px; box-shadow: var(--shadow); }
.progress-title, .progress-caption { display: flex; align-items: center; justify-content: space-between; gap: 12px; }
.progress-title strong { font-size: 20px; }
.icon-btn { width: 40px; height: 40px; border-radius: 13px; border: 1px solid var(--line); background: #fff; color: var(--primary); font-weight: 900; cursor: pointer; }
.progress-track { height: 8px; border-radius: 99px; overflow: hidden; margin: 10px 0 7px; background: #e5f1fb; }
.progress-track span { display: block; height: 100%; border-radius: inherit; background: linear-gradient(90deg, var(--primary), var(--primary-2)); }
.progress-caption { color: var(--muted); font-size: 11px; }
.progress-caption strong { color: var(--primary); }
.question-card { position: relative; overflow: hidden; margin: 14px auto 0; padding: 30px; border: 1px solid rgba(255,255,255,.8); border-radius: 28px; background: var(--card); box-shadow: var(--shadow); }
.question-card::after { content: ""; position: absolute; width: 150px; height: 150px; right: -60px; top: -70px; border-radius: 50%; background: #f1f8fe; }
.question-card-top { position: relative; z-index: 1; display: flex; justify-content: space-between; gap: 12px; }
.badge { display: inline-flex; width: fit-content; padding: 6px 10px; border-radius: 999px; color: var(--primary); background: var(--primary-soft); border: 1px solid #d4eaff; font-size: 11px; font-weight: 800; }
.question-code { color: var(--muted); font-size: 11px; }
.question-text { position: relative; z-index: 1; margin: 22px 0 14px; font-size: clamp(21px, 3vw, 29px); line-height: 1.55; }
.passage-box { position: relative; z-index: 1; margin-top: 18px; padding: 17px 19px; border-radius: 17px; background: #fff9e9; border: 1px solid #f5dda0; }
.passage-box strong { color: #9a6912; }
.passage-box p { margin: 7px 0 0; line-height: 1.8; }
.compact-passage { margin: 10px 0 14px; }
.source-actions { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 18px; }
.source-btn { display: inline-flex; align-items: center; justify-content: center; gap: 5px; padding: 9px 12px; border: 1px solid var(--line); border-radius: 12px; color: var(--text); background: #fff; font: inherit; font-size: 12px; font-weight: 700; cursor: pointer; text-decoration: none; }
.source-btn:hover { border-color: #91c9f7; color: var(--primary); }
.source-btn.muted { color: var(--muted); }
.choices { display: grid; gap: 10px; }
.choice { width: 100%; min-height: 60px; display: grid; grid-template-columns: 42px 1fr 22px; gap: 11px; align-items: center; padding: 11px 14px; text-align: left; color: var(--text); background: #fff; border: 1px solid var(--line); border-radius: 16px; cursor: pointer; transition: border-color .15s, background .15s, transform .15s; }
.choice:hover { transform: translateY(-1px); border-color: #9acdf7; background: #fafdff; }
.choice-letter { width: 36px; height: 36px; display: grid; place-items: center; border-radius: 12px; background: #f3f9ff; border: 1px solid var(--line); font-weight: 800; }
.choice i { width: 20px; height: 20px; border: 1.5px solid #c8dced; border-radius: 50%; }
.choice.selected { border-color: var(--primary); background: #f0f8ff; box-shadow: 0 8px 20px rgba(60,145,239,.10); }
.choice.selected .choice-letter { color: white; border-color: var(--primary); background: var(--primary); }
.choice.selected i { border: 6px solid var(--primary); }
.question-footer-info { display: flex; flex-wrap: wrap; gap: 9px; margin-top: 18px; color: var(--muted); font-size: 11px; }
.question-footer-info span { padding: 6px 9px; border-radius: 999px; background: #f5f9fd; }
.bottom-nav { position: fixed; z-index: 25; left: 50%; bottom: 14px; transform: translateX(-50%); width: min(720px, calc(100% - 24px)); display: grid; grid-template-columns: repeat(5, 1fr); padding: 7px; border: 1px solid rgba(216,232,246,.9); border-radius: 22px; background: rgba(255,255,255,.94); box-shadow: 0 16px 35px rgba(37,103,159,.18); backdrop-filter: blur(18px); }
.bottom-nav button { min-height: 54px; border: 0; border-radius: 16px; color: var(--muted); background: transparent; cursor: pointer; }
.bottom-nav button:hover, .bottom-nav button.active { color: var(--primary); background: var(--primary-soft); }
.bottom-nav button:disabled { opacity: .35; cursor: not-allowed; }
.bottom-nav span { display: block; font-size: 19px; font-weight: 900; }
.bottom-nav small { display: block; margin-top: 2px; font-size: 9px; font-weight: 700; }
.bottom-nav .submit-nav { color: white; background: linear-gradient(135deg, var(--primary), var(--primary-2)); }

.modal { position: fixed; inset: 0; z-index: 100; display: none; align-items: center; justify-content: center; padding: 18px; }
.modal.open { display: flex; }
.modal-backdrop { position: absolute; inset: 0; background: rgba(32,57,80,.58); backdrop-filter: blur(5px); }
.modal-card { position: relative; z-index: 1; width: min(760px, 100%); max-height: calc(100vh - 36px); overflow: auto; border: 1px solid rgba(255,255,255,.8); border-radius: 24px; background: #fff; box-shadow: 0 30px 70px rgba(12,43,68,.26); }
.small-card { max-width: 460px; padding: 28px; text-align: center; }
.modal-close { width: 42px; height: 42px; border: 1px solid var(--line); border-radius: 14px; color: var(--primary); background: #fff; font-size: 27px; cursor: pointer; }
.modal-close:not(.inline) { position: absolute; top: 14px; right: 14px; }
.modal-icon { width: 54px; height: 54px; display: grid; place-items: center; margin: 0 auto 12px; border-radius: 50%; color: white; background: var(--danger); font-size: 28px; font-weight: 900; }
.modal-actions { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; margin-top: 20px; }
.modal-head, .pdf-head { display: flex; align-items: center; justify-content: space-between; gap: 14px; padding: 14px 16px; border-bottom: 1px solid var(--line); background: #fff; }
.modal-head strong, .pdf-head strong { display: block; font-size: 17px; }
.modal-head small, .pdf-head span { display: block; margin-top: 2px; color: var(--muted); font-size: 11px; }
.sticky-head { position: sticky; top: 0; z-index: 2; }
.list-card { max-width: 820px; }
.question-list-body { padding: 15px; }
.question-list-section { padding: 10px 0 18px; }
.question-list-section + .question-list-section { border-top: 1px dashed var(--line); }
.question-list-section h3 { margin: 0 0 10px; color: var(--primary); font-size: 14px; }
.modal-number-grid { display: grid; grid-template-columns: repeat(10, 1fr); gap: 7px; }
.modal-q-number { aspect-ratio: 1; border: 1px solid var(--line); border-radius: 12px; color: var(--text); background: #f7fbff; font-weight: 800; cursor: pointer; }
.modal-q-number.answered { color: white; border-color: var(--primary); background: var(--primary); }
.modal-q-number.flagged { box-shadow: inset 0 0 0 3px #ffd36e; }
.modal-q-number.current { outline: 3px solid rgba(60,145,239,.25); }
.lecture-card { max-width: 1120px; }
.lecture-body { padding: 16px; background: #f6fbff; }
.lecture-section { padding: 18px; border: 1px solid var(--line); border-radius: 18px; background: #fbfdff; }
.lecture-section + .lecture-section { margin-top: 12px; }
.lecture-section h3 { margin: 0 0 9px; color: var(--primary); }
.lecture-section ul { margin: 0; padding-left: 23px; line-height: 1.8; }
.lecture-sources { display: flex; flex-wrap: wrap; gap: 7px; margin-top: 13px; }

.formula-tabs { position: sticky; z-index: 2; top: 70px; display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); gap: 8px; margin: -2px 0 14px; padding: 8px; border: 1px solid var(--line); border-radius: 18px; background: rgba(255,255,255,.96); box-shadow: 0 10px 28px rgba(42,103,159,.10); backdrop-filter: blur(16px); }
.formula-tab { min-height: 58px; display: flex; align-items: center; justify-content: center; gap: 7px; padding: 9px 7px; color: var(--muted); border: 1px solid transparent; border-radius: 13px; background: transparent; cursor: pointer; font-weight: 700; transition: .16s ease; }
.formula-tab span { min-width: 29px; height: 29px; display: grid; place-items: center; padding: 0 4px; border-radius: 9px; background: #f0f7fd; font-size: 14px; font-weight: 900; }
.formula-tab strong { font-size: 11px; line-height: 1.35; }
.formula-tab:hover { border-color: var(--line); background: #f8fbfe; }
.formula-tab.active { color: var(--primary); border-color: #9ccff8; background: #edf7ff; box-shadow: 0 7px 17px rgba(60,145,239,.09); }

.formula-guide { display: grid; gap: 14px; }
.formula-hero { display: grid; grid-template-columns: 64px 1fr; gap: 15px; align-items: center; padding: 22px 24px; border-radius: 22px; color: white; background: linear-gradient(135deg, #368eea, #75bafb); box-shadow: 0 16px 34px rgba(49,128,199,.16); }
.formula-hero.formula-aptitude { background: linear-gradient(135deg, #6c65d8, #9a8cf2); }
.formula-hero.formula-english { background: linear-gradient(135deg, #1b9b7b, #58c7a7); }
.formula-hero.formula-thai { background: linear-gradient(135deg, #e8863a, #f6b461); }
.formula-hero.formula-digital { background: linear-gradient(135deg, #247caa, #53b8cc); }
.formula-hero-icon { width: 58px; height: 58px; display: grid; place-items: center; border: 1px solid rgba(255,255,255,.35); border-radius: 18px; background: rgba(255,255,255,.16); font-size: 26px; font-weight: 900; }
.formula-hero span { display: block; font-size: 10px; font-weight: 800; opacity: .82; }
.formula-hero h2 { margin: 2px 0 1px; font-size: clamp(24px, 3vw, 34px); line-height: 1.25; }
.formula-hero p { margin: 0; font-size: 12px; opacity: .92; }
.formula-intro { margin: 0; padding: 15px 17px; color: #41566f; border: 1px solid var(--line); border-radius: 16px; background: white; font-size: 12px; line-height: 1.8; }

.formula-quick-card { padding: 18px 20px; border: 1px solid #b6daf8; border-radius: 18px; background: linear-gradient(135deg, #eef8ff, #fff); }
.formula-section-title { display: flex; align-items: center; gap: 10px; }
.formula-section-title > span { width: 37px; height: 37px; display: grid; place-items: center; border-radius: 11px; background: white; font-size: 18px; }
.formula-section-title strong, .formula-section-title small { display: block; }
.formula-section-title strong { color: var(--primary); font-size: 14px; }
.formula-section-title small { margin-top: 2px; color: var(--muted); font-size: 9px; }
.formula-quick-card ol { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 7px 25px; margin: 14px 0 0; padding-left: 23px; }
.formula-quick-card li { padding-left: 2px; color: #3d526a; font-size: 11px; line-height: 1.68; }
.formula-quick-card li::marker { color: var(--primary); font-weight: 900; }

.formula-groups { display: grid; gap: 10px; }
.formula-group { overflow: hidden; border: 1px solid var(--line); border-radius: 18px; background: white; }
.formula-group[open] { border-color: #9dcff6; box-shadow: 0 10px 24px rgba(45,113,171,.07); }
.formula-group summary { min-height: 68px; display: grid; grid-template-columns: 36px 1fr 24px; gap: 11px; align-items: center; padding: 12px 16px; cursor: pointer; list-style: none; }
.formula-group summary::-webkit-details-marker { display: none; }
.formula-group summary > span { width: 34px; height: 34px; display: grid; place-items: center; color: var(--primary); border-radius: 11px; background: var(--primary-soft); font-size: 12px; font-weight: 900; }
.formula-group summary strong, .formula-group summary small { display: block; }
.formula-group summary strong { font-size: 14px; line-height: 1.45; }
.formula-group summary small { margin-top: 3px; color: var(--muted); font-size: 10px; line-height: 1.45; }
.formula-group summary i { color: var(--primary); font-size: 19px; font-style: normal; transition: transform .15s ease; }
.formula-group[open] summary i { transform: rotate(180deg); }
.formula-group-body { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 10px; padding: 13px; border-top: 1px dashed var(--line); background: #f9fcff; }
.formula-item { min-width: 0; padding: 15px; border: 1px solid #dceaf7; border-radius: 15px; background: white; }
.formula-item-head { display: grid; gap: 8px; }
.formula-item-head strong { color: #213b59; font-size: 13px; }
.formula-item-head code { display: block; width: fit-content; max-width: 100%; padding: 7px 9px; white-space: normal; overflow-wrap: anywhere; color: #176db8; border: 1px solid #cce6fa; border-radius: 9px; background: #eff8ff; font-family: "Noto Sans Thai", system-ui, sans-serif; font-size: 11px; font-weight: 800; line-height: 1.55; }
.formula-item > p { margin: 9px 0 0; color: #53667c; font-size: 10px; line-height: 1.72; }
.formula-example, .formula-trap { display: grid; grid-template-columns: 54px 1fr; gap: 7px; margin-top: 9px; padding: 8px 9px; border-radius: 10px; font-size: 9px; line-height: 1.6; }
.formula-example { color: #297354; background: #eefaf5; border: 1px solid #cceee0; }
.formula-trap { color: #8b5b15; background: #fff8e9; border: 1px solid #f4dfac; }
.formula-example b, .formula-trap b { font-weight: 900; }
.formula-checklist { padding: 16px 18px; border: 1px solid #d7ccff; border-radius: 17px; background: linear-gradient(135deg, #f7f4ff, #fff); }
.formula-checklist > strong { color: #6b55ae; font-size: 13px; }
.formula-checklist > div { display: flex; flex-wrap: wrap; gap: 7px; margin-top: 10px; }
.formula-checklist span { padding: 7px 10px; color: #66558d; border: 1px solid #dfd6fa; border-radius: 999px; background: white; font-size: 9px; font-weight: 700; }
.pdf-card { width: min(1100px, 100%); height: min(870px, calc(100vh - 34px)); overflow: hidden; }
.pdf-head { height: 68px; }
.pdf-actions { display: flex; gap: 8px; align-items: center; }
.pdf-card iframe { width: 100%; height: calc(100% - 68px); border: 0; background: #edf3f8; }
.reference-card { max-width: 540px; padding: 30px; }
.reference-card h2 { margin: 8px 0; }
.reference-card p { color: var(--muted); line-height: 1.75; }

.result-page { padding: 35px 0 70px; }
.result-container { max-width: 940px; }
.result-hero { padding: 30px; text-align: center; border-radius: 28px; color: white; background: linear-gradient(135deg, #3d91ec, #78bdf9); box-shadow: var(--shadow); }
.result-hero .eyebrow { color: white; }
.result-hero h1 { margin: 5px 0 12px; }
.score-ring { width: 150px; height: 150px; display: grid; place-content: center; margin: 0 auto 10px; border-radius: 50%; background: rgba(255,255,255,.18); border: 1px solid rgba(255,255,255,.35); }
.score-ring strong { font-size: 58px; line-height: 1; }
.score-ring span { font-size: 13px; }
.result-hero p { margin: 0; opacity: .95; }
.result-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 10px; margin: 15px 0; }
.subject-result { padding: 15px; border: 1px solid var(--line); border-radius: 17px; background: #fff; box-shadow: 0 9px 22px rgba(53,112,163,.07); }
.subject-result span { display: block; min-height: 38px; color: var(--muted); font-size: 12px; }
.subject-result strong { color: var(--primary); font-size: 22px; }
.result-actions { display: flex; flex-wrap: wrap; gap: 8px; margin: 14px 0; }
.review-list { display: grid; gap: 14px; }
.review-card { padding: 21px; border: 1px solid var(--line); border-left: 5px solid var(--line); border-radius: 20px; background: #fff; box-shadow: 0 10px 28px rgba(40,100,154,.07); }
.review-card.correct { border-left-color: var(--success); }
.review-card.wrong { border-left-color: var(--danger); }
.review-card.unanswered { border-left-color: var(--warning); }
.review-head { display: flex; justify-content: space-between; gap: 15px; align-items: start; }
.review-head h3 { margin: 8px 0 0; font-size: 17px; line-height: 1.65; }
.status-pill { padding: 6px 10px; border-radius: 999px; font-size: 11px; font-weight: 800; }
.status-pill.correct { color: var(--success); background: #eaf9f3; }
.status-pill.wrong { color: var(--danger); background: #fff0f1; }
.status-pill.unanswered { color: #a66a09; background: #fff7e6; }
.review-answer { display: grid; gap: 5px; margin-top: 14px; padding: 13px 15px; border-radius: 14px; background: #f7fafc; }
.correct-text { color: var(--success); font-weight: 700; }
.wrong-text { color: var(--danger); font-weight: 700; }
.lecture-note { margin-top: 13px; padding: 15px; border-radius: 15px; background: #f2f8ff; border: 1px solid #dceeff; }
.lecture-note strong { color: var(--primary); }
.lecture-note p { margin: 6px 0 0; line-height: 1.75; color: #42556d; }
.review-source { display: flex; flex-wrap: wrap; gap: 8px 12px; align-items: center; margin-top: 12px; }
.review-source > span { color: var(--muted); font-size: 11px; flex: 1 1 320px; }
.empty-note { padding: 30px; text-align: center; border-radius: 18px; background: #fff; color: var(--muted); }

@media (max-width: 900px) {
  .setup-grid { grid-template-columns: 1fr; }
  .info-card { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px; }
  .info-card > .eyebrow, .info-card > h3, .info-card > p { grid-column: 1 / -1; }
  .info-stat { display: block; }
  .subject-cards { grid-template-columns: repeat(3, 1fr); }
  .result-grid { grid-template-columns: repeat(3, 1fr); }
}

@media (max-width: 680px) {
  .container { width: min(100% - 18px, 1080px); }
  .landing-page { padding-top: 14px; }
  .site-brand { margin: 0 5px 14px; }
  .site-brand strong { font-size: 18px; }
  .hero-card { grid-template-columns: 1fr; padding: 27px 23px; }
  .hero-orb { display: none; }
  .subject-cards { grid-template-columns: repeat(2, 1fr); }
  .subject-card { min-height: 116px; }
  .landing-actions { grid-template-columns: 1fr; }
  .info-card { grid-template-columns: 1fr; }
  .info-card > * { grid-column: auto; }
  .exam-header-inner { min-height: 66px; }
  .brand-inline span { display: none; }
  .brand-inline strong { font-size: 14px; }
  .timer-panel { min-width: 122px; padding: 6px 10px; }
  .timer-panel strong { font-size: 19px; }
  .question-card { padding: 21px 16px; border-radius: 22px; }
  .question-text { font-size: 21px; }
  .choice { grid-template-columns: 38px 1fr 20px; }
  .bottom-nav { bottom: 8px; }
  .bottom-nav small { font-size: 8px; }
  .modal { padding: 8px; }
  .modal-card { max-height: calc(100vh - 16px); border-radius: 20px; }
  .modal-number-grid { grid-template-columns: repeat(5, 1fr); }
  .modal-actions { grid-template-columns: 1fr; }
  .pdf-card { height: calc(100vh - 16px); }
  .pdf-head { padding: 10px; }
  .pdf-actions .btn { display: none; }
  .result-grid { grid-template-columns: repeat(2, 1fr); }
  .review-head { display: block; }
  .status-pill { display: inline-block; margin-top: 9px; }
  .formula-tabs { top: 70px; display: flex; overflow-x: auto; justify-content: flex-start; padding: 6px; }
  .formula-tab { min-width: 115px; }
  .formula-hero { grid-template-columns: 49px 1fr; padding: 18px 16px; }
  .formula-hero-icon { width: 46px; height: 46px; border-radius: 14px; font-size: 21px; }
  .formula-hero p { font-size: 10px; }
  .formula-intro { font-size: 10px; }
  .formula-quick-card { padding: 15px; }
  .formula-quick-card ol { grid-template-columns: 1fr; }
  .formula-group summary { grid-template-columns: 32px 1fr 20px; padding: 11px; }
  .formula-group summary > span { width: 30px; height: 30px; }
  .formula-group summary strong { font-size: 12px; }
  .formula-group summary small { font-size: 9px; }
  .formula-group-body { grid-template-columns: 1fr; padding: 9px; }
  .formula-item { padding: 12px; }
  .formula-example, .formula-trap { grid-template-columns: 49px 1fr; }
}

/* v5: แท็บสรุปส่วนสำคัญจากบทอ่าน */
.home-tabs { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; margin: 0 0 18px; padding: 7px; border: 1px solid rgba(210,230,247,.95); border-radius: 21px; background: rgba(255,255,255,.78); box-shadow: 0 12px 30px rgba(41,107,169,.09); backdrop-filter: blur(14px); }
.home-tab { min-height: 67px; display: grid; grid-template-columns: 42px 1fr; grid-template-rows: auto auto; column-gap: 10px; align-items: center; padding: 10px 15px; text-align: left; color: var(--muted); border: 1px solid transparent; border-radius: 16px; background: transparent; cursor: pointer; transition: .18s ease; }
.home-tab > span { grid-row: 1 / 3; width: 40px; height: 40px; display: grid; place-items: center; border-radius: 13px; background: #f2f8fd; font-size: 20px; }
.home-tab strong { align-self: end; color: var(--text); font-size: 14px; }
.home-tab small { align-self: start; font-size: 10px; }
.home-tab:hover { border-color: var(--line); background: #fbfdff; }
.home-tab.active { color: var(--primary); border-color: #aad5fa; background: var(--primary-soft); box-shadow: 0 8px 20px rgba(60,145,239,.09); }
.home-tab.active > span { background: #fff; }
.home-tab.active strong { color: var(--primary); }

.study-container { max-width: 1180px; }
.study-hero { display: flex; justify-content: space-between; align-items: center; gap: 25px; padding: 28px 31px; margin-bottom: 18px; border-radius: 26px; border: 1px solid rgba(255,255,255,.85); color: white; background: linear-gradient(135deg, #3288e8, #72b8f8); box-shadow: var(--shadow); }
.study-hero h1 { margin: 5px 0 6px; font-size: clamp(27px, 4vw, 42px); }
.study-hero p { max-width: 760px; margin: 0; line-height: 1.75; opacity: .94; }
.study-hero .eyebrow { color: white; }
.study-hero .btn { flex: 0 0 auto; min-width: 220px; }

.study-layout { display: grid; grid-template-columns: 300px minmax(0, 1fr); gap: 17px; align-items: start; }
.study-topic-panel { position: sticky; top: 16px; padding: 17px; border: 1px solid rgba(255,255,255,.82); border-radius: 23px; background: rgba(255,255,255,.94); box-shadow: var(--shadow); }
.study-topic-title { display: flex; justify-content: space-between; gap: 10px; align-items: end; margin-bottom: 12px; }
.study-topic-title strong { font-size: 17px; }
.study-topic-title small { color: var(--muted); font-size: 10px; }
.study-topic-tabs { display: grid; gap: 8px; }
.study-topic-tab { width: 100%; min-height: 68px; display: grid; grid-template-columns: 40px 1fr 20px; gap: 9px; align-items: center; padding: 10px; text-align: left; color: var(--text); border: 1px solid var(--line); border-radius: 15px; background: #f9fcff; cursor: pointer; transition: .16s ease; }
.study-topic-tab > span { width: 38px; height: 38px; display: grid; place-items: center; border-radius: 12px; background: #fff; font-size: 19px; }
.study-topic-tab strong { display: block; font-size: 11px; line-height: 1.45; }
.study-topic-tab small { display: block; margin-top: 3px; color: var(--muted); font-size: 9px; }
.study-topic-tab i { color: #9cb3c8; font-size: 25px; font-style: normal; }
.study-topic-tab:hover { transform: translateX(2px); border-color: #9fcff7; }
.study-topic-tab.active { color: var(--primary); border-color: #8fc9f8; background: #edf7ff; box-shadow: 0 7px 18px rgba(60,145,239,.1); }
.study-topic-tab.active strong { color: var(--primary); }
.study-topic-tab.active i { color: var(--primary); }
.study-note { margin-top: 13px; padding: 13px; border-radius: 14px; background: #f3f8fd; border: 1px dashed #bfdcf3; }
.study-note strong { color: var(--primary); font-size: 12px; }
.study-note p { margin: 5px 0 0; color: var(--muted); font-size: 10px; line-height: 1.7; }

.study-content { min-width: 0; }
.reading-guide-detail { padding: 24px; border: 1px solid rgba(255,255,255,.85); border-radius: 25px; background: rgba(255,255,255,.95); box-shadow: var(--shadow); }
.reading-guide-head { display: grid; grid-template-columns: 62px 1fr; gap: 15px; align-items: start; padding-bottom: 18px; border-bottom: 1px dashed var(--line); }
.reading-guide-icon { width: 60px; height: 60px; display: grid; place-items: center; border-radius: 19px; background: linear-gradient(145deg, #e6f4ff, #fff); border: 1px solid var(--line); font-size: 29px; }
.reading-guide-head h2 { margin: 5px 0 7px; font-size: clamp(23px, 3vw, 31px); }
.reading-guide-head p { margin: 0; color: var(--muted); line-height: 1.8; font-size: 13px; }
.reading-warning { margin-top: 15px; padding: 15px 17px; border-radius: 15px; border: 1px solid #f3d38e; background: #fff8e9; }
.reading-warning strong { color: #9d680d; }
.reading-warning p { margin: 5px 0 0; color: #755522; line-height: 1.7; font-size: 12px; }

.quick-summary-card { margin-top: 17px; padding: 18px 20px; border-radius: 18px; border: 1px solid #b8dcfa; background: linear-gradient(135deg, #eff8ff, #fbfdff); }
.summary-card-title { display: flex; align-items: center; gap: 10px; margin-bottom: 11px; }
.summary-card-title > span { width: 38px; height: 38px; display: grid; place-items: center; border-radius: 12px; background: #fff; font-size: 19px; }
.summary-card-title strong, .summary-card-title small { display: block; }
.summary-card-title strong { color: var(--primary); font-size: 15px; }
.summary-card-title small { margin-top: 2px; color: var(--muted); font-size: 10px; }
.quick-summary-card ol { margin: 0; padding-left: 23px; }
.quick-summary-card li { padding: 5px 0 5px 4px; line-height: 1.72; font-size: 13px; }
.quick-summary-card li::marker { color: var(--primary); font-weight: 800; }

.reading-sections { display: grid; gap: 9px; margin-top: 15px; }
.reading-section { overflow: hidden; border: 1px solid var(--line); border-radius: 16px; background: #fff; }
.reading-section[open] { border-color: #a8d5f8; box-shadow: 0 8px 20px rgba(46,126,192,.06); }
.reading-section summary { min-height: 57px; display: grid; grid-template-columns: 32px 1fr 24px; gap: 10px; align-items: center; padding: 11px 14px; cursor: pointer; list-style: none; }
.reading-section summary::-webkit-details-marker { display: none; }
.reading-section summary > span { width: 30px; height: 30px; display: grid; place-items: center; border-radius: 10px; color: var(--primary); background: var(--primary-soft); font-weight: 800; font-size: 11px; }
.reading-section summary strong { font-size: 13px; line-height: 1.5; }
.reading-section summary i { color: var(--primary); font-style: normal; font-size: 19px; transition: transform .15s ease; }
.reading-section[open] summary i { transform: rotate(180deg); }
.reading-section-body { padding: 0 17px 16px 55px; border-top: 1px dashed var(--line); }
.reading-section-body ul { margin: 13px 0 0; padding-left: 20px; }
.reading-section-body li { padding: 4px 0; color: #3d5067; font-size: 12px; line-height: 1.75; }
.reading-section-body li::marker { color: var(--primary); }

.memory-card { margin-top: 15px; padding: 17px 19px; border-radius: 17px; border: 1px solid #d7ccff; background: linear-gradient(135deg, #f8f5ff, #fff); }
.memory-card > div { display: flex; align-items: center; gap: 8px; }
.memory-card > div span { font-size: 21px; }
.memory-card > div strong { color: #7056bd; }
.memory-card ul { display: grid; grid-template-columns: repeat(2, minmax(0,1fr)); gap: 7px 20px; margin: 12px 0 0; padding-left: 19px; }
.memory-card li { color: #584b75; font-size: 11px; line-height: 1.65; }

.reading-reference-card { display: flex; justify-content: space-between; gap: 18px; align-items: center; margin-top: 15px; padding: 16px 18px; border: 1px solid var(--line); border-radius: 17px; background: #f9fcff; }
.reading-reference-card strong, .reading-reference-card small { display: block; }
.reading-reference-card small { margin-top: 3px; color: var(--muted); font-size: 10px; }
.reading-reference-card .lecture-sources { justify-content: flex-end; margin: 0; }

@media (max-width: 900px) {
  .study-layout { grid-template-columns: 1fr; }
  .study-topic-panel { position: static; }
  .study-topic-tabs { grid-template-columns: repeat(2, minmax(0,1fr)); }
  .study-topic-tab:hover { transform: none; }
  .reading-reference-card { display: block; }
  .reading-reference-card .lecture-sources { justify-content: flex-start; margin-top: 12px; }
}

@media (max-width: 680px) {
  .home-tabs { gap: 6px; padding: 5px; border-radius: 17px; }
  .home-tab { min-height: 61px; grid-template-columns: 34px 1fr; padding: 8px 9px; }
  .home-tab > span { width: 32px; height: 32px; border-radius: 10px; font-size: 16px; }
  .home-tab strong { font-size: 11px; }
  .home-tab small { font-size: 8px; }
  .study-hero { display: block; padding: 23px 19px; }
  .study-hero p { font-size: 12px; }
  .study-hero .btn { width: 100%; min-width: 0; margin-top: 16px; }
  .study-topic-tabs { grid-template-columns: 1fr; }
  .reading-guide-detail { padding: 16px; border-radius: 20px; }
  .reading-guide-head { grid-template-columns: 48px 1fr; gap: 11px; }
  .reading-guide-icon { width: 47px; height: 47px; border-radius: 15px; font-size: 23px; }
  .reading-guide-head p { font-size: 11px; }
  .quick-summary-card { padding: 15px; }
  .quick-summary-card li { font-size: 11px; }
  .reading-section-body { padding-left: 17px; }
  .memory-card ul { grid-template-columns: 1fr; }
  .reading-reference-card { padding: 14px; }
  .source-btn { width: 100%; justify-content: center; }
}