:root {
  color-scheme: light;
  --bg: #f4f7fb;
  --surface: #ffffff;
  --surface-subtle: #f8fafc;
  --surface-strong: #edf3fb;
  --text: #10233f;
  --text-soft: #51647f;
  --text-faint: #8190a5;
  --line: #dbe4ef;
  --line-strong: #c9d6e6;
  --primary: #1768d5;
  --primary-strong: #0d4fae;
  --primary-soft: #eaf3ff;
  --green: #16835b;
  --green-soft: #e9f7f1;
  --amber: #b26a06;
  --amber-soft: #fff4de;
  --rose: #c63b56;
  --rose-soft: #fff0f3;
  --shadow-sm: 0 1px 2px rgba(15, 35, 64, .05), 0 8px 24px rgba(28, 55, 90, .05);
  --shadow-md: 0 18px 50px rgba(22, 48, 83, .12);
  --radius-sm: 9px;
  --radius: 14px;
  --radius-lg: 20px;
  --sidebar-width: 264px;
  --content-max: 1440px;
  --ease: 160ms ease;
  font-family: "Segoe UI Variable", "Segoe UI", Inter, system-ui, -apple-system, sans-serif;
  font-synthesis: none;
}

:root[data-theme="dark"] {
  color-scheme: dark;
  --bg: #0b1320;
  --surface: #111c2c;
  --surface-subtle: #162234;
  --surface-strong: #1a2b43;
  --text: #edf4ff;
  --text-soft: #adbed4;
  --text-faint: #7f93ad;
  --line: #26364b;
  --line-strong: #354861;
  --primary: #5da1ff;
  --primary-strong: #87b9ff;
  --primary-soft: #18345a;
  --green: #54c89a;
  --green-soft: #16382d;
  --amber: #f0b85c;
  --amber-soft: #402e16;
  --rose: #ff8197;
  --rose-soft: #48202a;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, .18), 0 12px 30px rgba(0, 0, 0, .16);
  --shadow-md: 0 24px 60px rgba(0, 0, 0, .34);
}

* { box-sizing: border-box; }
html { min-width: 320px; background: var(--bg); scroll-behavior: smooth; }
body { margin: 0; min-width: 320px; min-height: 100vh; min-height: 100dvh; overflow-x: hidden; background: var(--bg); color: var(--text); font-size: 15px; line-height: 1.55; }
button, input, textarea, select { font: inherit; color: inherit; }
button { cursor: pointer; }
button:disabled, input:disabled { cursor: not-allowed; opacity: .56; }
img { display: block; max-width: 100%; }
a { color: inherit; }
h1, h2, h3, p { margin-top: 0; }
h1, h2, h3 { color: var(--text); letter-spacing: -.035em; line-height: 1.16; }
h1 { margin-bottom: 0; font-size: clamp(1.85rem, 3vw, 2.6rem); }
h2 { margin-bottom: .4rem; font-size: clamp(1.45rem, 2vw, 2rem); }
h3 { margin-bottom: .45rem; font-size: 1.08rem; }
::selection { background: var(--primary); color: #fff; }
:focus-visible { outline: 3px solid color-mix(in srgb, var(--primary) 34%, transparent); outline-offset: 2px; }
.muted { color: var(--text-soft); }
.wide { grid-column: 1 / -1; }
.full { width: 100%; }
.ti { flex: 0 0 auto; font-size: 1.2em; line-height: 1; }

.workspace { display: grid; grid-template-columns: var(--sidebar-width) minmax(0, 1fr); min-height: 100vh; min-height: 100dvh; }
.sidebar { position: sticky; top: 0; z-index: 30; display: flex; flex-direction: column; min-width: 0; height: 100vh; height: 100dvh; overflow-y: auto; border-right: 1px solid var(--line); background: color-mix(in srgb, var(--surface) 96%, transparent); padding: 24px 16px 18px; }
.brand { display: flex; align-items: center; gap: 12px; min-width: 0; padding: 0 6px 24px; }
.brand > div:last-of-type { min-width: 0; }
.brand strong, .brand small { display: block; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.brand strong { font-size: 1.03rem; }
.brand small { margin-top: 2px; color: var(--text-faint); font-size: .78rem; }
.brand-mark { display: grid; flex: 0 0 48px; width: 48px; height: 48px; place-items: center; overflow: hidden; border: 1px solid var(--line); border-radius: 13px; background: #fff; box-shadow: var(--shadow-sm); }
.brand-mark img { width: 42px; height: 42px; object-fit: contain; }
.role-caption, .eyebrow { color: var(--text-faint); font-size: .72rem; font-weight: 800; letter-spacing: .12em; text-transform: uppercase; }
.role-caption { padding: 0 12px 10px; }
.side-nav { display: grid; gap: 5px; }
.nav-item { display: flex; align-items: center; gap: 12px; width: 100%; min-height: 45px; border: 1px solid transparent; border-radius: 11px; background: transparent; padding: 0 13px; color: var(--text-soft); font-weight: 650; text-align: left; transition: background var(--ease), color var(--ease), border-color var(--ease), transform var(--ease); }
.nav-item:hover { border-color: var(--line); background: var(--surface-subtle); color: var(--text); }
.nav-item:active { transform: translateY(1px); }
.nav-item.active { border-color: color-mix(in srgb, var(--primary) 20%, var(--line)); background: var(--primary-soft); color: var(--primary-strong); }
.nav-icon { width: 20px; font-size: 1.2rem; }
.side-footer { display: grid; gap: 12px; margin-top: auto; border-top: 1px solid var(--line); padding: 18px 6px 0; }
.mini-profile, .participant-cell { display: flex; align-items: center; gap: 10px; min-width: 0; }
.mini-profile > div, .participant-cell > div { min-width: 0; }
.mini-profile strong, .mini-profile small, .participant-cell strong, .participant-cell small { display: block; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.mini-profile strong, .participant-cell strong { font-size: .88rem; }
.mini-profile small, .participant-cell small { color: var(--text-faint); font-size: .74rem; }
.avatar { display: grid; flex: 0 0 40px; width: 40px; height: 40px; place-items: center; border-radius: 50%; background: var(--primary-soft); color: var(--primary-strong); font-size: .78rem; font-weight: 800; }
.avatar.small { flex-basis: 34px; width: 34px; height: 34px; }
.avatar.large { flex-basis: 54px; width: 54px; height: 54px; font-size: .92rem; }
.theme-button { display: flex; align-items: center; gap: 9px; min-height: 40px; border: 0; border-radius: 9px; background: transparent; padding: 0 10px; color: var(--text-soft); text-align: left; }
.theme-button:hover { background: var(--surface-subtle); color: var(--text); }
.sidebar-close, .mobile-header, .sidebar-backdrop { display: none; }
.main-content { width: 100%; min-width: 0; max-width: var(--content-max); margin: 0 auto; padding: 34px clamp(24px, 4vw, 58px) 72px; }
.topbar { display: flex; align-items: flex-start; justify-content: space-between; gap: 24px; margin-bottom: 42px; }
.topbar-actions { display: flex; align-items: center; gap: 10px; padding-top: 8px; }
.connection-dot { display: inline-flex; align-items: center; gap: 7px; color: var(--text-faint); font-size: .78rem; white-space: nowrap; }
.connection-dot .ti { color: var(--green); font-size: 1rem; }

.primary-button, .quiet-button, .danger-button, .text-button, .table-action, .card-link, .icon-button, .back-link, .oauth-button, .option-remove, .uploaded-file-remove { display: inline-flex; align-items: center; justify-content: center; gap: 8px; min-height: 42px; border-radius: var(--radius-sm); font-weight: 700; transition: background var(--ease), color var(--ease), border-color var(--ease), transform var(--ease), box-shadow var(--ease); }
.primary-button { border: 1px solid var(--primary); background: var(--primary); padding: 0 17px; color: #fff; box-shadow: 0 5px 14px color-mix(in srgb, var(--primary) 20%, transparent); }
.primary-button:hover { border-color: var(--primary-strong); background: var(--primary-strong); }
.quiet-button, .oauth-button { border: 1px solid var(--line-strong); background: var(--surface); padding: 0 16px; color: var(--text); }
.quiet-button:hover, .oauth-button:hover { border-color: color-mix(in srgb, var(--primary) 42%, var(--line)); background: var(--primary-soft); color: var(--primary-strong); }
.danger-button { border: 1px solid color-mix(in srgb, var(--rose) 50%, var(--line)); background: var(--rose-soft); padding: 0 16px; color: var(--rose); }
.danger-button:hover { border-color: var(--rose); }
.text-button, .back-link, .card-link, .table-action { min-height: 34px; border: 0; background: transparent; padding: 0; color: var(--primary-strong); }
.text-button:hover, .back-link:hover, .card-link:hover, .table-action:hover { color: var(--primary); text-decoration: underline; text-underline-offset: 3px; }
.table-action { min-height: 34px; padding: 0 7px; white-space: nowrap; }
.table-action.danger, .danger-icon { color: var(--rose); }
.icon-button, .sidebar-close, .option-remove, .uploaded-file-remove { flex: 0 0 40px; width: 40px; height: 40px; min-height: 40px; border: 1px solid var(--line); background: var(--surface); padding: 0; color: var(--text-soft); }
.icon-button:hover, .sidebar-close:hover { border-color: var(--line-strong); background: var(--surface-subtle); color: var(--text); }
.primary-button:active, .quiet-button:active, .danger-button:active, .icon-button:active { transform: translateY(1px); }

.page-intro, .section-heading, .class-header, .panel-heading, .table-head, .composer-header, .config-heading, .form-title { display: flex; align-items: flex-start; justify-content: space-between; gap: 24px; }
.page-intro { align-items: center; margin-bottom: 32px; }
.page-intro .lede { margin-bottom: 5px; color: var(--text); font-size: clamp(1.05rem, 1.5vw, 1.3rem); font-weight: 750; }
.page-intro p:last-child { margin-bottom: 0; }
.section-heading { align-items: end; margin: 42px 0 17px; }
.section-heading h2 { margin: 4px 0 0; font-size: 1.25rem; }
.breadcrumb { display: flex; align-items: center; gap: 10px; min-width: 0; margin: -14px 0 26px; color: var(--text-faint); font-size: .82rem; }
.breadcrumb > span:last-child { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.class-header { align-items: end; margin-bottom: 22px; }
.class-header > div:first-child { min-width: 0; }
.class-header h2 { margin: 7px 0; }
.class-header p { max-width: 760px; margin-bottom: 0; color: var(--text-soft); }
.header-actions, .action-row, .form-actions, .question-tab-actions, .bulk-member-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 10px; }
.header-actions { justify-content: flex-end; }
.panel, .table-card, .form-card, .question-composer, .result-card, .loading-card { border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); box-shadow: var(--shadow-sm); }
.panel, .table-card, .form-card, .question-composer { padding: clamp(18px, 2.5vw, 28px); }
.loading-card { display: grid; min-height: 220px; place-items: center; color: var(--text-soft); }
.panel-heading { margin-bottom: 22px; }
.panel-heading p { margin: 6px 0 0; }
.stats-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 16px; }
.stat-card { position: relative; min-width: 0; overflow: hidden; border: 1px solid var(--line); border-top: 3px solid var(--primary); border-radius: var(--radius); background: var(--surface); padding: 22px; box-shadow: var(--shadow-sm); }
.stat-card::after { position: absolute; right: -26px; bottom: -28px; width: 86px; height: 86px; border-radius: 50%; background: var(--primary-soft); content: ""; }
.stat-card.green { border-top-color: var(--green); }
.stat-card.green::after { background: var(--green-soft); }
.stat-card.amber { border-top-color: var(--amber); }
.stat-card.amber::after { background: var(--amber-soft); }
.stat-card.rose { border-top-color: var(--rose); }
.stat-card.rose::after { background: var(--rose-soft); }
.stat-label, .stat-detail { color: var(--text-soft); font-size: .8rem; }
.stat-value { margin: 11px 0 3px; font-size: 2rem; font-weight: 800; letter-spacing: -.04em; }
.class-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 320px), 1fr)); gap: 18px; }
.class-card { display: flex; flex-direction: column; min-width: 0; min-height: 300px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); padding: 24px; box-shadow: var(--shadow-sm); transition: border-color var(--ease), transform var(--ease), box-shadow var(--ease); }
.class-card:hover { border-color: var(--line-strong); transform: translateY(-2px); box-shadow: var(--shadow-md); }
.class-card-top { display: flex; align-items: center; justify-content: space-between; gap: 10px; }
.software-label { color: var(--primary-strong); font-size: .72rem; font-weight: 850; letter-spacing: .11em; text-transform: uppercase; }
.class-card h3 { margin: 18px 0 8px; font-size: 1.26rem; }
.class-card > p { flex: 1; margin-bottom: 20px; color: var(--text-soft); }
.class-meta { display: flex; flex-wrap: wrap; gap: 8px 16px; border-bottom: 1px solid var(--line); padding-bottom: 14px; color: var(--text-faint); font-size: .76rem; }
.class-progress { margin-top: 14px; }
.class-progress > div:first-child { display: flex; justify-content: space-between; gap: 10px; color: var(--text-soft); font-size: .78rem; }
.class-progress strong { color: var(--text); }
.progress-track { height: 6px; margin: 9px 0 14px; overflow: hidden; border-radius: 999px; background: var(--surface-strong); }
.progress-track i { display: block; height: 100%; border-radius: inherit; background: var(--primary); }
.class-progress.status-only { border-top: 1px solid var(--line); padding-top: 14px; }
.card-link { align-self: flex-end; margin-top: auto; }
.status-pill { display: inline-flex; align-items: center; width: fit-content; min-height: 28px; border-radius: 999px; padding: 4px 10px; background: var(--primary-soft); color: var(--primary-strong); font-size: .7rem; font-weight: 800; line-height: 1.15; }
.status-pill.green { background: var(--green-soft); color: var(--green); }
.status-pill.amber { background: var(--amber-soft); color: var(--amber); }
.status-pill.rose { background: var(--rose-soft); color: var(--rose); }
.empty-state { display: grid; min-height: 260px; place-items: center; align-content: center; border: 1px dashed var(--line-strong); border-radius: var(--radius); background: var(--surface-subtle); padding: 38px 24px; text-align: center; }
.empty-state h3 { margin: 13px 0 6px; }
.empty-state p { max-width: 420px; margin-bottom: 18px; color: var(--text-soft); }
.empty-mark { display: grid; width: 48px; height: 48px; place-items: center; border-radius: 13px; background: var(--primary-soft); color: var(--primary-strong); font-size: 1.45rem; }

form label, .form-card label, .question-composer label { display: grid; gap: 7px; min-width: 0; color: var(--text-soft); font-size: .79rem; font-weight: 700; }
.field-hint { color: var(--muted); font-size: .72rem; font-weight: 500; line-height: 1.45; }
input, textarea, select { width: 100%; min-width: 0; border: 1px solid var(--line-strong); border-radius: var(--radius-sm); background: var(--surface); padding: 11px 12px; color: var(--text); outline: none; transition: border-color var(--ease), box-shadow var(--ease), background var(--ease); }
input { min-height: 43px; }
textarea { resize: vertical; }
input:focus, textarea:focus, select:focus { border-color: var(--primary); box-shadow: 0 0 0 3px color-mix(in srgb, var(--primary) 13%, transparent); }
input[type="checkbox"], input[type="radio"] { width: 17px; min-height: 17px; height: 17px; padding: 0; accent-color: var(--primary); }
input[type="file"] { min-height: auto; border: 0; background: transparent; padding: 0; }
.form-card, .settings-form, .inline-form { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; margin-bottom: 24px; }
.inline-form { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.inline-form > div:first-child, .form-title { grid-column: 1 / -1; }
.form-title { align-items: center; }
.form-title strong { font-size: 1.08rem; }
.form-hint { margin: -3px 0 0; color: var(--text-faint); font-size: .78rem; }
.check-label { display: flex !important; grid-auto-flow: column; align-items: center; justify-content: flex-start; gap: 9px !important; align-self: end; min-height: 43px; }
.join-form { grid-template-columns: minmax(0, 1fr) auto; align-items: end; }

.tabs { display: flex; gap: 2px; overflow-x: auto; border-bottom: 1px solid var(--line); margin-bottom: 26px; scrollbar-width: none; }
.tabs::-webkit-scrollbar { display: none; }
.tab { flex: 0 0 auto; min-height: 46px; border: 0; border-bottom: 2px solid transparent; background: transparent; padding: 0 14px; color: var(--text-soft); font-weight: 700; white-space: nowrap; }
.tab:hover { color: var(--text); }
.tab.active { border-color: var(--primary); color: var(--primary-strong); }
.table-card { padding: 0; overflow: hidden; }
.table-head { align-items: center; padding: 22px 24px; }
.table-head h2 { margin: 3px 0 0; font-size: 1.2rem; }
.table-wrap, .bulk-member-table-wrap { width: 100%; min-width: 0; overflow-x: auto; }
table { width: 100%; border-collapse: collapse; }
th, td { border-top: 1px solid var(--line); padding: 15px 18px; text-align: left; vertical-align: middle; }
th { background: var(--surface-subtle); color: var(--text-faint); font-size: .7rem; font-weight: 850; letter-spacing: .06em; text-transform: uppercase; white-space: nowrap; }
td { color: var(--text-soft); font-size: .84rem; }
td strong, td small { display: block; }
td strong { color: var(--text); }
td small { margin-top: 3px; color: var(--text-faint); }
tbody tr:hover { background: color-mix(in srgb, var(--primary-soft) 34%, transparent); }
.participant-table-wrap table, .table-card table { min-width: 720px; }

.detail-grid, .account-grid { display: grid; grid-template-columns: minmax(0, 1.6fr) minmax(290px, .74fr); gap: 18px; }
.instruction-copy { color: var(--text-soft); }
.rule-list, .metric-list, .profile-detail { display: grid; margin: 22px 0; border-top: 1px solid var(--line); }
.rule-list > div, .metric-list > div, .profile-detail > div { display: flex; align-items: center; justify-content: space-between; gap: 20px; border-bottom: 1px solid var(--line); padding: 13px 0; }
.rule-list span, .metric-list span, .profile-detail span { color: var(--text-faint); font-size: .8rem; }
.code-value { color: var(--primary-strong); letter-spacing: .12em; }
.participant-status p { color: var(--text-soft); }
.setting-row { display: flex; align-items: center; justify-content: space-between; gap: 20px; border-top: 1px solid var(--line); padding: 16px 0; }
.setting-row strong, .setting-row small { display: block; }
.setting-row small { margin-top: 4px; color: var(--text-faint); }

.member-panel { padding: 0; overflow: hidden; }
.member-panel > .panel-heading { margin: 0; padding: 24px; }
.member-add-collapsed { border-top: 1px solid var(--line); padding: 18px 24px; }
.member-add-grid { display: grid; grid-template-columns: minmax(260px, .68fr) minmax(420px, 1.32fr); gap: 16px; border-top: 1px solid var(--line); background: var(--surface-subtle); padding: 20px 24px; }
.member-add-card { display: grid; align-content: start; gap: 16px; min-width: 0; border: 1px solid var(--line); border-radius: 12px; background: var(--surface); padding: 20px; }
.member-add-card h3 { margin: 5px 0; }
.member-add-card p { margin-bottom: 0; }
.bulk-member-table-wrap { border: 1px solid var(--line); border-radius: 10px; }
.bulk-member-table th, .bulk-member-table td { padding: 10px 12px; }
.bulk-member-table input { min-width: 220px; }
.bulk-member-actions { justify-content: space-between; }
.member-actions { display: flex; align-items: center; gap: 7px; }

.question-panel { overflow: hidden; }
.question-list { display: grid; gap: 12px; }
.question-card { min-width: 0; border: 1px solid var(--line); border-radius: 13px; background: var(--surface); padding: 18px; transition: border-color var(--ease), background var(--ease), box-shadow var(--ease), transform var(--ease); }
.question-card[data-action="edit-question"] { cursor: pointer; }
.question-card[data-action="edit-question"]:hover { border-color: color-mix(in srgb, var(--primary) 45%, var(--line)); background: color-mix(in srgb, var(--primary-soft) 30%, var(--surface)); box-shadow: var(--shadow-sm); }
.question-card.is-editing { border-color: color-mix(in srgb, var(--primary) 54%, var(--line)); background: var(--primary-soft); padding: 0; }
.question-card.dragging { opacity: .5; }
.question-card.drag-over { border-color: var(--primary); transform: translateY(3px); }
.question-card h3 { margin: 14px 0 8px; overflow-wrap: anywhere; }
.question-card-top, .question-order, .question-card-tools, .question-card-meta { display: flex; align-items: center; gap: 10px; }
.question-card-top { justify-content: space-between; }
.question-card-meta { flex-wrap: wrap; color: var(--text-faint); font-size: .76rem; }
.question-card-meta span + span::before { margin-right: 10px; content: "•"; }
.question-number { display: grid; flex: 0 0 34px; width: 34px; height: 34px; place-items: center; border-radius: 9px; background: var(--primary-soft); color: var(--primary-strong); font-weight: 800; }
.drag-handle { display: inline-flex; align-items: center; justify-content: center; width: 32px; height: 36px; color: var(--text-faint); cursor: grab; }
.drag-handle:active { cursor: grabbing; }
.inline-edit-note { color: var(--primary-strong); font-size: .76rem; font-weight: 700; }
.question-attachment { margin-top: 11px; color: var(--text-faint); font-size: .76rem; overflow-wrap: anywhere; }
.question-composer { display: grid; gap: 20px; margin: 0; border: 0; border-radius: 12px; background: color-mix(in srgb, var(--surface) 88%, var(--primary-soft)); box-shadow: none; }
.composer-header { align-items: center; }
.question-type-picker { display: grid; grid-template-columns: minmax(220px, .6fr) minmax(0, 1.4fr); gap: 14px; align-items: end; }
.type-explainer, .auto-grade-note, .manual-grade-note { border-radius: 10px; background: var(--surface); padding: 13px 15px; color: var(--text-soft); font-size: .8rem; }
.question-config { display: grid; gap: 14px; border: 1px solid var(--line); border-radius: 12px; background: var(--surface); padding: 18px; }
.config-heading { align-items: center; }
.config-heading span { color: var(--text-faint); font-size: .76rem; }
.choice-builder { display: grid; gap: 9px; }
.choice-row { display: grid !important; grid-template-columns: 22px 34px minmax(0, 1fr) 40px; align-items: center; gap: 9px !important; }
.choice-letter, .uploaded-file-icon, .upload-job-icon { display: grid; place-items: center; border-radius: 8px; background: var(--surface-strong); color: var(--primary-strong); font-weight: 800; }
.choice-letter { width: 34px; height: 34px; }
.option-remove { color: var(--rose); }
.config-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 14px; }
.auto-grade-note { background: var(--green-soft); color: var(--green); }
.manual-grade-note { display: flex; gap: 12px; background: var(--amber-soft); color: var(--amber); }
.manual-grade-note p { margin: 3px 0 0; color: inherit; }
.config-icon { font-weight: 900; }
.keyword-field > span, .reference-upload > span { color: var(--text-faint); font-weight: 500; }
.reference-upload { border: 1px dashed var(--line-strong); border-radius: 11px; padding: 16px; }
.reference-upload small { color: var(--text-faint); font-weight: 500; overflow-wrap: anywhere; }
.composer-footer { display: flex; align-items: end; justify-content: space-between; gap: 18px; }
.composer-footer > label { width: min(180px, 100%); }
.save-hint { color: var(--text-faint); font-size: .76rem; }

.filter-row { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 16px; }
.filter-chip { min-height: 35px; border: 1px solid var(--line); border-radius: 999px; background: var(--surface); padding: 0 13px; color: var(--text-soft); font-weight: 700; }
.filter-chip.active { border-color: var(--primary); background: var(--primary-soft); color: var(--primary-strong); }
.answer-review { margin-top: 18px; border-top: 1px solid var(--line); }
.answer-review-row { display: grid; grid-template-columns: minmax(0, 1fr) minmax(300px, .58fr); gap: 24px; border-bottom: 1px solid var(--line); padding: 20px 0; }
.answer-review-row > div { min-width: 0; }
.answer-review-row p { margin-bottom: 0; color: var(--text-soft); overflow-wrap: anywhere; }
.grade-form { display: grid; grid-template-columns: minmax(90px, .45fr) minmax(140px, 1fr) auto; gap: 9px; align-items: center; }
.submission-files { grid-column: 1 / -1; min-width: 0; margin-top: 10px; }
.submission-files > strong { display: block; margin-bottom: 8px; color: var(--text-soft); font-size: .72rem; letter-spacing: .06em; text-transform: uppercase; }
.submission-file { display: flex; align-items: center; gap: 10px; width: 100%; min-width: 0; border: 1px solid var(--line); border-radius: 10px; background: var(--surface-subtle); padding: 10px 12px; color: var(--primary-strong); text-align: left; }
.submission-file + .submission-file { margin-top: 8px; }
.submission-file span { min-width: 0; flex: 1; overflow-wrap: anywhere; word-break: break-word; }
.uploaded-file-list, .upload-job-list { display: grid; gap: 8px; margin-top: 14px; }
.uploaded-file-heading { display: flex; justify-content: space-between; gap: 12px; color: var(--text-soft); font-size: .78rem; }
.uploaded-file-item, .upload-job { display: grid; grid-template-columns: 36px minmax(0, 1fr) auto 40px; align-items: center; gap: 10px; min-width: 0; border: 1px solid var(--line); border-radius: 10px; background: var(--surface); padding: 9px 10px; }
.uploaded-file-item > span:nth-child(2), .upload-job > span:nth-child(2) { min-width: 0; overflow-wrap: anywhere; word-break: break-word; }
.uploaded-file-item small, .upload-job small { color: var(--text-faint); }
.uploaded-file-icon, .upload-job-icon { width: 36px; height: 36px; font-size: .65rem; }
.uploaded-file-remove { color: var(--rose); }
.upload-job { grid-template-columns: 36px minmax(0, 1fr) auto; }
.upload-job.uploading .upload-job-icon { animation: pulse 1s ease infinite; }

.exam-shell { width: min(1180px, 100%); margin: 0 auto; }
.exam-top { display: flex; align-items: flex-start; justify-content: space-between; gap: 24px; margin-bottom: 26px; }
.exam-top p { margin: 8px 0 0; }
.timer-box { display: grid; flex: 0 0 150px; min-height: 92px; place-items: center; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); padding: 12px; box-shadow: var(--shadow-sm); }
.timer-box span { color: var(--text-faint); font-size: .75rem; }
.timer-box strong { color: var(--primary-strong); font-size: 1.8rem; letter-spacing: .04em; }
.exam-progress-bar { display: flex; align-items: center; justify-content: space-between; gap: 18px; margin-bottom: 18px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); padding: 14px 16px; }
.exam-progress-bar > span { color: var(--text-soft); font-size: .8rem; white-space: nowrap; }
.exam-progress-dots { display: flex; flex-wrap: wrap; justify-content: flex-end; gap: 7px; }
.exam-dot, .exam-index-item { display: grid; width: 36px; height: 36px; place-items: center; border: 1px solid var(--line-strong); border-radius: 9px; background: var(--surface); color: var(--text-soft); font-weight: 800; }
.exam-dot.done, .exam-index-item.done { border-color: color-mix(in srgb, var(--green) 55%, var(--line)); background: var(--green-soft); color: var(--green); }
.exam-dot.active { border-color: var(--primary); box-shadow: 0 0 0 3px color-mix(in srgb, var(--primary) 12%, transparent); color: var(--primary-strong); }
.exam-question { min-width: 0; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); padding: clamp(18px, 3vw, 30px); box-shadow: var(--shadow-sm); }
.question-heading { display: flex; align-items: flex-start; gap: 15px; }
.question-heading > div { min-width: 0; }
.question-heading h2 { margin: 7px 0 0; font-size: clamp(1.1rem, 2vw, 1.35rem); overflow-wrap: anywhere; }
.question-reference { overflow: hidden; border: 1px solid var(--line); border-radius: 12px; background: var(--surface-subtle); margin: 22px 0; padding: 12px; }
.question-reference img { max-height: 520px; margin: 0 auto; object-fit: contain; }
.question-reference figcaption { margin-top: 9px; color: var(--text-faint); font-size: .73rem; text-align: center; }
.question-reference-link { display: inline-flex; align-items: center; gap: 8px; margin: 18px 0; color: var(--primary-strong); font-weight: 700; }
.option-list { display: grid; gap: 10px; margin-top: 22px; }
.option-card { display: grid !important; grid-template-columns: 20px 36px minmax(0, 1fr); align-items: center; gap: 12px !important; border: 1px solid var(--line); border-radius: 11px; background: var(--surface); padding: 13px 15px; color: var(--text-soft) !important; cursor: pointer; }
.option-card:hover { border-color: var(--line-strong); background: var(--surface-subtle); }
.option-card:has(input:checked) { border-color: var(--primary); background: var(--primary-soft); color: var(--text) !important; }
.option-letter { display: grid; width: 34px; height: 34px; place-items: center; border-radius: 8px; background: var(--surface-strong); color: var(--text); font-weight: 850; }
.answer-textarea { min-height: 180px; margin-top: 22px; }
.file-upload-area { margin-top: 22px; }
.upload-drop { position: relative; display: grid !important; min-height: 150px; place-items: center; align-content: center; border: 1px dashed var(--line-strong); border-radius: 12px; background: var(--surface-subtle); padding: 24px; text-align: center; cursor: pointer; }
.upload-drop > .ti { color: var(--primary-strong); font-size: 1.8rem; }
.upload-drop input { position: absolute; inset: 0; width: 100%; height: 100%; opacity: 0; cursor: pointer; }
.upload-drop strong { color: var(--text); }
.upload-drop span { color: var(--text-faint); font-weight: 500; }
.autosave-note { margin-top: 17px; color: var(--text-faint); font-size: .75rem; }
.exam-navigation { display: grid; grid-template-columns: 1fr auto 1fr; align-items: center; gap: 14px; margin-top: 18px; }
.exam-navigation > :first-child { justify-self: start; }
.exam-navigation > :last-child { justify-self: end; }
.exam-navigation > span { color: var(--text-faint); font-size: .78rem; text-align: center; }
.exam-layout { display: grid; grid-template-columns: 190px minmax(0, 1fr); gap: 20px; }
.exam-index { display: grid; align-content: start; gap: 9px; }
.exam-questions { min-width: 0; }

.auth-layout { display: grid; grid-template-columns: minmax(360px, .9fr) minmax(480px, 1.1fr); min-width: 0; min-height: 100vh; min-height: 100dvh; }
.auth-visual { position: relative; display: flex; flex-direction: column; min-width: 0; overflow: hidden; background: linear-gradient(145deg, #0b315f 0%, #0b57b8 72%, #1978e8 100%); padding: clamp(28px, 5vw, 72px); color: #fff; }
.auth-visual::after { position: absolute; right: -15%; bottom: -20%; width: 70%; aspect-ratio: 1; border: 1px solid rgba(255,255,255,.16); border-radius: 50%; box-shadow: 0 0 0 70px rgba(255,255,255,.035), 0 0 0 140px rgba(255,255,255,.025); content: ""; }
.brand.inverse { position: relative; z-index: 1; padding: 0; }
.brand.inverse .brand-mark { background: #fff; }
.brand.inverse strong { color: #fff; }
.brand.inverse small { color: rgba(255,255,255,.68); }
.auth-message { position: relative; z-index: 1; max-width: 620px; margin: auto 0; padding: 90px 0; }
.auth-message .eyebrow { color: #9ecbff; }
.auth-message h1 { margin: 18px 0; color: #fff; font-size: clamp(2.4rem, 5vw, 5rem); }
.auth-message em { color: #aad1ff; font-style: normal; }
.auth-message p { max-width: 520px; color: rgba(255,255,255,.76); font-size: 1.05rem; }
.auth-footer { position: relative; z-index: 1; color: rgba(255,255,255,.58); font-size: .72rem; }
.auth-panel { display: grid; min-width: 0; place-items: center; padding: clamp(24px, 6vw, 80px); }
.auth-card { width: min(440px, 100%); min-width: 0; }
.auth-card h2 { margin: 10px 0; }
.auth-card form { display: grid; gap: 15px; margin-top: 24px; }
.oauth-button { margin-top: 12px; }
.demo-accounts { display: grid; gap: 3px; margin-top: 18px; border: 1px solid var(--line); border-radius: 10px; background: var(--surface-subtle); padding: 13px; color: var(--text-faint); font-size: .74rem; }
.demo-accounts strong { color: var(--text-soft); }
.auth-links { display: flex; justify-content: space-between; gap: 12px; margin-top: 20px; }
.auth-links button { display: inline-flex; align-items: center; gap: 7px; border: 0; background: transparent; padding: 0; color: var(--primary-strong); }
.callout { border-radius: 10px; padding: 12px 14px; font-size: .82rem; }
.callout.warning { background: var(--amber-soft); color: var(--amber); }
.result-card { width: min(720px, 100%); margin: 70px auto 0; padding: clamp(28px, 5vw, 54px); text-align: center; }
.result-score { margin: 28px 0; color: var(--primary-strong); font-size: clamp(3.5rem, 8vw, 6rem); font-weight: 850; letter-spacing: -.06em; }
.result-score span { font-size: 1rem; letter-spacing: 0; }
.toast { position: fixed; right: 22px; bottom: 22px; z-index: 90; max-width: min(430px, calc(100vw - 32px)); border: 1px solid var(--line); border-radius: 11px; background: var(--surface); padding: 13px 16px; color: var(--text); box-shadow: var(--shadow-md); opacity: 0; pointer-events: none; transform: translateY(10px); transition: opacity var(--ease), transform var(--ease); }
.toast.visible { opacity: 1; transform: translateY(0); }
.toast.error { border-color: color-mix(in srgb, var(--rose) 45%, var(--line)); color: var(--rose); }
.ui-modal-backdrop { position: fixed; inset: 0; z-index: 100; display: grid; place-items: center; background: rgba(7, 17, 31, .56); padding: 20px; backdrop-filter: blur(4px); }
.ui-modal { width: min(470px, 100%); border: 1px solid var(--line); border-radius: var(--radius-lg); background: var(--surface); padding: 26px; box-shadow: var(--shadow-md); }
.ui-modal h2 { margin: 9px 0; font-size: 1.45rem; }
.ui-modal p { color: var(--text-soft); }
.ui-modal-actions { display: flex; justify-content: flex-end; gap: 10px; margin-top: 24px; }
.switch-control { display: flex; align-items: center; justify-content: space-between; gap: 18px; min-height: 58px; border: 1px solid var(--line); border-radius: 12px; background: var(--surface); padding: 12px 14px; cursor: pointer; }
.switch-control > span:first-child { display: grid; gap: 3px; }
.switch-control small { color: var(--text-faint); font-weight: 500; }
.switch-control input { position: absolute; width: 1px; height: 1px; opacity: 0; pointer-events: none; }
.switch-track { position: relative; flex: 0 0 auto; width: 46px; height: 26px; border-radius: 999px; background: var(--line-strong); transition: background var(--ease); }
.switch-track::after { content: ""; position: absolute; top: 3px; left: 3px; width: 20px; height: 20px; border-radius: 50%; background: #fff; box-shadow: 0 2px 7px rgba(7, 17, 31, .2); transition: transform var(--ease); }
.switch-control input:checked + .switch-track { background: var(--primary); }
.switch-control input:checked + .switch-track::after { transform: translateX(20px); }
.switch-control:focus-within { border-color: var(--primary); box-shadow: 0 0 0 3px var(--primary-soft); }
.file-type-restriction { display: grid; gap: 12px; }
.file-type-options { display: grid; gap: 14px; border: 1px solid var(--line); border-radius: 12px; background: var(--surface-subtle); padding: 16px; }
.file-type-options.is-hidden { display: none; }
.file-type-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 9px; }
.file-type-option { display: flex; align-items: center; gap: 9px; min-height: 42px; border: 1px solid var(--line); border-radius: 9px; background: var(--surface); padding: 9px 11px; color: var(--text-soft); cursor: pointer; }
.file-type-option:has(input:checked) { border-color: var(--primary); background: var(--primary-soft); color: var(--primary-strong); }
.file-type-option input { width: 17px; height: 17px; margin: 0; accent-color: var(--primary); }
.file-type-option .ti { font-size: 1.1rem; }
.custom-extension { display: grid; gap: 7px; }

@keyframes pulse { 50% { opacity: .45; transform: scale(.92); } }

@media (max-width: 1180px) {
  :root { --sidebar-width: 232px; }
  .stats-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .inline-form { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .detail-grid, .account-grid { grid-template-columns: 1fr; }
  .member-add-grid { grid-template-columns: 1fr; }
}

@media (max-width: 860px) {
  .workspace { display: block; padding-top: 64px; }
  .mobile-header { position: fixed; inset: 0 0 auto; z-index: 25; display: flex; align-items: center; justify-content: space-between; height: 64px; border-bottom: 1px solid var(--line); background: color-mix(in srgb, var(--surface) 94%, transparent); padding: 0 16px; backdrop-filter: blur(14px); }
  .mobile-brand { display: flex; align-items: center; gap: 9px; }
  .mobile-brand img { width: 34px; height: 34px; object-fit: contain; }
  .sidebar { position: fixed; inset: 0 auto 0 0; z-index: 50; width: min(84vw, 300px); height: 100dvh; box-shadow: var(--shadow-md); transform: translateX(-105%); transition: transform 220ms ease; }
  .sidebar.open { transform: translateX(0); }
  .sidebar-close { display: inline-flex; margin-left: auto; }
  .sidebar-backdrop { position: fixed; inset: 0; z-index: 40; display: block; border: 0; background: rgba(7, 17, 31, .5); opacity: 0; pointer-events: none; transition: opacity 220ms ease; }
  .sidebar-backdrop.visible { opacity: 1; pointer-events: auto; }
  .main-content { padding: 26px 20px 56px; }
  .topbar { margin-bottom: 30px; }
  .topbar-actions .icon-button { display: none; }
  .member-panel > .panel-heading, .member-add-collapsed { padding-inline: 18px; }
  .member-add-grid { padding: 16px 18px; }
  .answer-review-row { grid-template-columns: 1fr; }
  .grade-form { max-width: 100%; }
  .auth-layout { grid-template-columns: minmax(0, 1fr); }
  .auth-visual { min-height: 280px; padding: 28px; }
  .auth-message { padding: 48px 0 22px; }
  .auth-message h1 { font-size: clamp(2.2rem, 10vw, 3.7rem); }
  .auth-message h1, .auth-message em { max-width: 100%; overflow-wrap: anywhere; }
  .auth-footer { display: none; }
  .auth-panel { padding: 38px 22px 56px; }
}

@media (max-width: 640px) {
  body { font-size: 14px; }
  .main-content { padding-inline: 15px; }
  .topbar { align-items: center; gap: 12px; margin-bottom: 24px; }
  .topbar h1 { font-size: 1.65rem; }
  .topbar .eyebrow { display: none; }
  .connection-dot span { display: none; }
  .page-intro, .section-heading, .class-header, .panel-heading, .table-head, .composer-header, .form-title { align-items: stretch; flex-direction: column; gap: 13px; }
  .page-intro { margin-bottom: 24px; }
  .page-intro > button, .page-intro > .primary-button, .page-intro > .quiet-button { width: 100%; }
  .section-heading { margin-top: 32px; }
  .header-actions { justify-content: flex-start; }
  .stats-grid, .form-card, .settings-form, .inline-form, .join-form, .question-type-picker, .config-grid { grid-template-columns: 1fr; }
  .stat-card { padding: 17px; }
  .stat-value { font-size: 1.65rem; }
  .class-card { min-height: 270px; padding: 19px; }
  .panel, .form-card, .question-composer { padding: 17px; }
  .member-panel { padding: 0; }
  .tabs { margin-inline: -15px; padding-inline: 8px; }
  .tab { padding-inline: 11px; }
  .composer-footer { align-items: stretch; flex-direction: column; }
  .composer-footer > label { width: 100%; }
  .question-card { padding: 14px; }
  .question-card-tools .inline-edit-note { display: none; }
  .choice-row { grid-template-columns: 20px 32px minmax(0, 1fr) 38px; }
  .exam-top { align-items: stretch; flex-direction: column; }
  .timer-box { grid-auto-flow: column; flex-basis: auto; min-height: 62px; justify-content: space-between; padding-inline: 16px; }
  .timer-box strong { font-size: 1.5rem; }
  .exam-progress-bar { align-items: stretch; flex-direction: column; }
  .exam-progress-dots { justify-content: flex-start; }
  .exam-question { padding: 17px; }
  .question-heading { gap: 10px; }
  .option-card { grid-template-columns: 18px 32px minmax(0, 1fr); padding: 11px; }
  .exam-navigation { grid-template-columns: 1fr 1fr; }
  .exam-navigation > span { grid-column: 1 / -1; grid-row: 1; }
  .exam-navigation > :first-child { grid-column: 1; grid-row: 2; width: 100%; }
  .exam-navigation > :last-child { grid-column: 2; grid-row: 2; width: 100%; }
  .uploaded-file-item { grid-template-columns: 34px minmax(0, 1fr) 38px; }
  .uploaded-file-item small { grid-column: 2; }
  .upload-job { grid-template-columns: 34px minmax(0, 1fr); }
  .upload-job small { grid-column: 2; }
  .grade-form { grid-template-columns: 1fr; }
  .grade-form button { width: 100%; }
  .auth-visual { min-height: 235px; }
  .auth-message { padding: 30px 0 0; }
  .auth-message p { display: none; }
  .auth-panel { padding-inline: 18px; }
  .ui-modal-actions { display: grid; grid-template-columns: 1fr 1fr; }
  .file-type-grid { grid-template-columns: 1fr; }
  .toast { right: 16px; bottom: 16px; left: 16px; max-width: none; }
}

@media (max-width: 420px) {
  .mobile-brand strong { font-size: .92rem; }
  .class-meta { gap: 6px 12px; }
  .question-card-top { align-items: flex-start; }
  .question-card-tools { justify-content: flex-end; }
  .question-card-tools .table-action { min-width: 40px; overflow: hidden; }
  .exam-navigation { gap: 8px; }
  .exam-navigation button { padding-inline: 10px; font-size: .8rem; }
  .auth-links { align-items: flex-start; flex-direction: column; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: .01ms !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; }
}