:root {
  color-scheme: light;
  --paper: #f6f5f0;
  --white: #fffefa;
  --ink: #202a25;
  --muted: #536052;
  --line: #dce1d6;
  --control-border: #7b8778;
  --green: #d4f47d;
  --green-hover: #c6e86c;
  --darkgreen: #344b37;
  --surface: #edf0e7;
  --success-bg: #e7f1da;
  --success-ink: #2e582a;
  --amber: #fff0cf;
  --warning-ink: #775016;
  --error-bg: #fff0e9;
  --error-ink: #923e21;
  --focus: #38602d;
  --qr-surface: #ffffff;
  --space-1: .25rem;
  --space-2: .5rem;
  --space-3: .75rem;
  --space-4: 1rem;
  --space-5: 1.5rem;
  --space-6: 2rem;
  --space-7: 3rem;
  --radius-sm: .375rem;
  --radius-md: .625rem;
  --text-sm: .875rem;
  --text-base: 1rem;
  --text-title: 2rem;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Arial, sans-serif;
  --ease: cubic-bezier(.22, 1, .36, 1);
  --duration: 160ms;
  --z-skip: 10;
}

* { box-sizing: border-box; }
html { scroll-padding-top: var(--space-4); }
body { margin: 0; background: var(--paper); color: var(--ink); font: var(--text-base)/1.55 var(--font); }
a { color: inherit; text-decoration: none; }
button, input, select, textarea { font: inherit; }
button, summary { cursor: pointer; }
button { color: inherit; }
button, a, input, select, textarea, summary, [tabindex] { outline-offset: 4px; }
:focus-visible { outline: 3px solid var(--focus); }
h1, h2, h3, p { margin-top: 0; }
h1, h2, h3 { overflow-wrap: anywhere; text-wrap: balance; }
h1 { font-size: var(--text-title); line-height: 1.2; letter-spacing: -.025em; font-weight: 650; margin: 0 0 var(--space-3); }
h1.smaller { font-size: var(--text-title); max-width: 40ch; }
h2 { font-size: 1.25rem; line-height: 1.35; letter-spacing: -.015em; }
h3 { font-size: 1.125rem; line-height: 1.4; letter-spacing: -.01em; }
p { max-width: 72ch; text-wrap: pretty; }
strong { font-weight: 650; }
.muted, .small, small { color: var(--muted); }
.small, small { font-size: var(--text-sm); }
.lead { color: var(--muted); font-size: var(--text-base); line-height: 1.6; }
.eyebrow { margin-bottom: var(--space-3); color: var(--muted); font-size: var(--text-sm); overflow-wrap: anywhere; }
.sr-only, caption.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip-path: inset(50%); white-space: nowrap; border: 0; }
.skip-link { position: fixed; top: var(--space-2); left: var(--space-4); z-index: var(--z-skip); transform: translateY(-200%); padding: var(--space-3) var(--space-4); background: var(--white); border: 1px solid var(--focus); border-radius: var(--radius-sm); font-weight: 600; }
.skip-link:focus { transform: translateY(0); }

/* Existing shell and identity, shared by every route. */
.topbar { min-height: 72px; padding: var(--space-3) max(var(--space-5), calc((100% - 1200px)/2)); display: flex; align-items: center; gap: var(--space-5); border-bottom: 1px solid var(--line); background: var(--white); }
.brand { min-height: 44px; font-size: 1.375rem; font-weight: 750; display: inline-flex; align-items: center; gap: var(--space-2); letter-spacing: -.025em; flex-shrink: 0; }
.brand-icon { display: block; height: 32px; width: 32px; flex-shrink: 0; }
.brand-wordmark { display: block; width: 156px; height: 24px; flex-shrink: 0; }
.account { margin-left: auto; display: flex; gap: var(--space-4); align-items: center; min-width: 0; font-size: var(--text-sm); }
.account-name { max-width: 30ch; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.account form { margin: 0; flex-shrink: 0; }
.text-button { min-height: 44px; min-width: 44px; background: transparent; border: 1px solid transparent; border-radius: var(--radius-sm); padding: var(--space-2) var(--space-3); font-size: var(--text-sm); text-decoration: underline; text-underline-offset: 3px; }
.navigation { padding: 0 max(var(--space-5), calc((100% - 1200px)/2)); min-height: 56px; display: flex; align-items: stretch; gap: var(--space-5); border-bottom: 1px solid var(--line); }
.navigation > a { display: flex; align-items: center; min-height: 48px; padding: var(--space-2) 0; border-bottom: 2px solid transparent; color: var(--muted); font-size: var(--text-sm); }
.navigation > a[aria-current="page"] { border-bottom-color: var(--darkgreen); color: var(--ink); font-weight: 650; }
.nav-role { margin-left: auto; align-self: center; font-size: var(--text-sm); color: var(--muted); }
.container { width: 100%; max-width: 1248px; margin: auto; padding: var(--space-6) var(--space-5) var(--space-7); min-height: calc(100vh - 220px); }
.page-heading { display: flex; align-items: center; justify-content: space-between; gap: var(--space-5); margin-bottom: var(--space-5); }
.page-heading > div { min-width: 0; }
.page-heading .lead { margin-bottom: 0; }
.page-heading > .button { flex-shrink: 0; }

/* Shared action states. */
.button { min-height: 44px; min-width: 44px; border: 1px solid var(--control-border); border-radius: var(--radius-sm); padding: .625rem var(--space-4); display: inline-flex; align-items: center; justify-content: center; gap: var(--space-2); background: var(--white); color: var(--ink); font-size: var(--text-sm); font-weight: 600; line-height: 1.45; text-align: center; transition: background-color var(--duration) var(--ease), border-color var(--duration) var(--ease); }
.button.primary { background: var(--green); border-color: var(--darkgreen); }
.button.subtle { background: transparent; }
.button.wide { width: 100%; }
.button:active:not(:disabled), .text-button:active:not(:disabled) { background: var(--surface); }
.button.primary:active:not(:disabled) { background: var(--green-hover); }
:is(button, input, select, textarea):disabled { cursor: not-allowed; }
.button:disabled, .text-button:disabled { background: var(--surface); border-color: var(--control-border); color: var(--muted); }
[aria-busy="true"] .button:disabled { cursor: progress; }
.text-link, .auth-bottom a { color: var(--darkgreen); text-decoration: underline; text-underline-offset: 3px; }
.text-link, .back { display: inline-flex; align-items: center; min-height: 44px; font-size: var(--text-sm); }
.back { margin-bottom: var(--space-4); color: var(--darkgreen); text-decoration: underline; text-underline-offset: 3px; }
.actions { display: flex; gap: var(--space-2); align-items: center; flex-wrap: wrap; }
.actions form { margin: 0; }

/* Counts orient the user without dominating the journal. */
.stats { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); border: 1px solid var(--line); border-radius: var(--radius-md); overflow: hidden; background: var(--white); margin-bottom: var(--space-6); }
.stat { padding: var(--space-4) var(--space-5); border-right: 1px solid var(--line); display: flex; flex-direction: column; gap: var(--space-1); min-width: 0; }
.stat:last-child { border-right: 0; }
.stat > span { display: flex; justify-content: space-between; gap: var(--space-2); color: var(--muted); font-size: var(--text-sm); }
.stat > strong { font-size: 1.75rem; font-weight: 600; line-height: 1.3; font-variant-numeric: tabular-nums; }
.stat small { font-size: var(--text-sm); }
.stat-alert { background: var(--amber); }
.stat-alert > span, .stat-alert small { color: var(--warning-ink); }
.section-heading { display: flex; align-items: center; justify-content: space-between; gap: var(--space-4); margin: var(--space-6) 0 var(--space-4); }
.section-heading h2 { margin: 0; }
.section-heading > span, .section-heading h2 span { font-size: var(--text-sm); font-weight: 400; }
.lecture-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 280px), 1fr)); gap: var(--space-4); }
.lecture-card { min-width: 0; background: var(--white); border: 1px solid var(--line); border-radius: var(--radius-md); padding: var(--space-5); display: flex; flex-direction: column; transition: border-color var(--duration) var(--ease), background-color var(--duration) var(--ease); }
.card-top { display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: var(--space-2); margin-bottom: var(--space-4); font-size: var(--text-sm); }
.lecture-card h3 { margin-bottom: var(--space-2); }
.lecture-card > p { color: var(--muted); font-size: var(--text-sm); margin-bottom: var(--space-5); }
.card-bottom { border-top: 1px solid var(--line); padding-top: var(--space-4); display: flex; align-items: center; justify-content: space-between; margin-top: auto; font-size: var(--text-sm); color: var(--muted); gap: var(--space-3); }
.card-bottom > span:first-child { overflow-wrap: anywhere; }
.arrow { flex-shrink: 0; font-size: 1.25rem; color: var(--darkgreen); }
.badge { display: inline-block; font-size: var(--text-sm); font-weight: 500; border: 1px solid var(--line); padding: var(--space-1) var(--space-2); border-radius: var(--radius-sm); background: var(--surface); color: var(--muted); overflow-wrap: anywhere; }
a.badge { display: inline-flex; align-items: center; min-height: 44px; text-decoration: underline; text-underline-offset: 3px; border-color: var(--control-border); }
.badge.green { background: var(--success-bg); color: var(--success-ink); }
.badge.warning { background: var(--amber); color: var(--warning-ink); }

/* Panels, notices and progressively disclosed details. */
.panel { min-width: 0; border: 1px solid var(--line); border-radius: var(--radius-md); background: var(--white); padding: var(--space-5); margin-bottom: var(--space-5); }
.panel.compact { padding: var(--space-3) var(--space-5); margin-top: var(--space-5); }
.panel h2 { margin-bottom: var(--space-3); }
.panel p { color: var(--muted); overflow-wrap: anywhere; }
summary { min-height: 44px; padding: var(--space-2) 0; font-size: var(--text-sm); font-weight: 600; }
details[open] > summary { margin-bottom: var(--space-3); }
.info-strip { display: flex; gap: var(--space-4); align-items: flex-start; margin-top: var(--space-6); padding: var(--space-5) 0 0; border-top: 1px solid var(--line); }
.info-strip p { font-size: var(--text-sm); color: var(--muted); margin: 0; }
.info-strip strong { color: var(--ink); }
.empty { border: 1px dashed var(--control-border); border-radius: var(--radius-md); padding: var(--space-6) var(--space-5); text-align: center; }
.empty p { color: var(--muted); margin-inline: auto; }
.empty-icon { display: inline-grid; place-items: center; width: 44px; height: 44px; background: var(--surface); border-radius: var(--radius-md); font-size: 1.5rem; margin-bottom: var(--space-4); color: var(--darkgreen); }
.notice { padding: var(--space-4); background: var(--surface); color: var(--ink); border: 1px solid var(--line); border-radius: var(--radius-sm); margin-bottom: var(--space-5); font-size: var(--text-sm); overflow-wrap: anywhere; }
.notice.warning { background: var(--amber); color: var(--warning-ink); }
.notice.error { background: var(--error-bg); color: var(--error-ink); }
.notice.success { background: var(--success-bg); color: var(--success-ink); }
.notice p { margin: var(--space-2) 0; color: inherit; }
.notice ul { padding-left: var(--space-5); margin-bottom: 0; }
.notice a { text-decoration: underline; text-underline-offset: 3px; }

/* Native controls remain familiar and readable on a phone. */
label { display: block; font-size: var(--text-sm); font-weight: 600; color: var(--ink); margin-bottom: var(--space-2); }
input, select, textarea { display: block; width: 100%; min-width: 0; min-height: 44px; border: 1px solid var(--control-border); border-radius: var(--radius-sm); background: var(--white); padding: .625rem var(--space-3); margin-top: var(--space-2); color: var(--ink); font-size: var(--text-base); }
textarea { resize: vertical; }
input::placeholder, textarea::placeholder { color: var(--muted); opacity: 1; }
input:focus, textarea:focus, select:focus { border-color: var(--focus); outline: 3px solid var(--focus); outline-offset: 2px; }
[aria-invalid="true"] { border-color: var(--error-ink); }
input[type="checkbox"] { width: 24px; min-height: 24px; display: inline-block; vertical-align: middle; }
.helptext { font-size: var(--text-sm); color: var(--muted); display: block; line-height: 1.6; margin: var(--space-2) 0 0; }
.helptext ul { padding-left: var(--space-5); margin-bottom: 0; }
.errorlist { font-size: var(--text-sm); color: var(--error-ink); padding-left: var(--space-5); margin: var(--space-2) 0; }
.field { margin-bottom: var(--space-5); }
.field .helptext { font-weight: 400; }
.form-panel { max-width: 680px; }
.report-list { list-style: none; padding: 0; margin: var(--space-5) 0; }
.report-list > li { border-top: 1px solid var(--line); padding: var(--space-5) 0; }
.report-heading { display: flex; align-items: baseline; justify-content: space-between; gap: var(--space-4); }
.report-heading h2 { margin: 0; min-width: 0; }
.report-heading .badge { flex-shrink: 0; }
.report-list .small { margin: var(--space-2) 0; overflow-wrap: anywhere; }
.report-description { white-space: pre-wrap; overflow-wrap: anywhere; }
.inline-form { display: flex; align-items: flex-end; gap: var(--space-4); margin-top: var(--space-4); }
.inline-form label { margin: 0; flex: 1; }

/* The attendance journal remains a real, keyboard-scrollable table. */
.window-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--space-4); }
.window-grid .panel { margin-bottom: 0; }
.window-grid .eyebrow { color: var(--ink); font-weight: 600; }
.window-grid p { font-size: var(--text-sm); }
.live-dot { display: inline-block; width: 8px; height: 8px; background: var(--success-ink); border-radius: 50%; margin-right: var(--space-2); }
.table-hint { margin: var(--space-3) 0; font-size: var(--text-sm); color: var(--muted); }
.table-wrap { position: relative; max-width: 100%; overflow-x: auto; background: var(--white); border: 1px solid var(--line); border-radius: var(--radius-md); }
table { border-collapse: collapse; width: 100%; font-size: var(--text-sm); text-align: left; }
th { background: var(--surface); color: var(--ink); font-weight: 600; padding: var(--space-4); vertical-align: top; }
td { padding: var(--space-4); border-top: 1px solid var(--line); vertical-align: top; overflow-wrap: anywhere; }
td strong { font-weight: 650; }
.attendance-table { min-width: 760px; }
.attendance-table th:first-child { min-width: 200px; }
.history-table { min-width: 600px; }
.empty-cell { text-align: center; padding: var(--space-6) var(--space-4); color: var(--muted); }
.check { display: inline-grid; place-items: center; width: 28px; height: 28px; background: var(--surface); color: var(--muted); border-radius: 50%; }
.check.yes { background: var(--success-bg); color: var(--success-ink); }
.detail-content { min-width: 240px; max-width: 340px; padding-top: var(--space-3); }
.detail-content form { display: grid; gap: var(--space-3); }
.detail-content .button { margin-top: var(--space-2); }
.detail-content p { color: var(--muted); }
.detail-content label { margin: 0; }
.approval { display: grid; grid-template-columns: minmax(0, 1.3fr) minmax(0, 1fr); gap: var(--space-6); }
.approval h2 { margin: var(--space-4) 0 var(--space-2); overflow-wrap: anywhere; }
.approval p { font-size: var(--text-sm); }
.approval form { display: grid; align-content: start; gap: var(--space-3); }
.approval form .button { justify-self: start; }
.timeline > div { display: flex; gap: var(--space-4); border-top: 1px solid var(--line); padding-top: var(--space-4); margin-top: var(--space-4); }
.timeline time { font-size: var(--text-sm); color: var(--muted); min-width: 125px; font-variant-numeric: tabular-nums; }
.timeline p { font-size: var(--text-sm); margin-bottom: var(--space-3); }
.narrow { max-width: 620px; margin: var(--space-4) auto; }
.auth-layout { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: var(--space-7); align-items: start; margin: var(--space-6) auto; max-width: 1040px; }
.auth-intro { padding-block: var(--space-5); }
.auth-intro h1 { max-width: 24ch; }
.intro-steps { padding-left: var(--space-5); color: var(--muted); }
.intro-steps li { padding: var(--space-2) 0; }
.auth-panel { max-width: 480px; width: 100%; }
.auth-panel h2 { font-size: 1.5rem; margin: 0 0 var(--space-3); }
.auth-panel > p { font-size: var(--text-sm); }
.auth-panel .text-link { margin-top: var(--space-3); }
.auth-bottom { border-top: 1px solid var(--line); padding-top: var(--space-4); margin-top: var(--space-5); font-size: var(--text-sm); color: var(--muted); }
.auth-bottom a { display: inline-flex; align-items: center; min-height: 44px; margin-left: var(--space-2); }
footer { padding: var(--space-4) max(var(--space-5), calc((100% - 1200px)/2)); border-top: 1px solid var(--line); display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: var(--space-4); font-size: var(--text-sm); color: var(--muted); }

/* Projector announcements are separate from its changing countdown. */
.projector-page .navigation, .projector-page footer { display: none; }
.projector-page .container { max-width: 1400px; }
.projector h1 { font-size: 2rem; margin-bottom: var(--space-5); }
.projector-layout { display: grid; grid-template-columns: minmax(280px, 560px) minmax(0, 1fr); gap: var(--space-7); align-items: center; }
.qr-image { aspect-ratio: 1; min-width: 0; background: var(--qr-surface); border: 1px solid var(--line); border-radius: var(--radius-md); display: grid; place-items: center; padding: var(--space-3); }
.qr-image svg { width: 100%; height: 100%; display: block; }
.qr-layer { grid-area: 1 / 1; width: 100%; height: 100%; min-width: 0; background: var(--qr-surface); }
.qr-layer-enter { animation: qr-reveal 160ms cubic-bezier(0.25, 1, 0.5, 1); }
@keyframes qr-reveal { from { opacity: 0; } to { opacity: 1; } }
.qr-image p { color: var(--muted); text-align: center; padding: var(--space-5); }
.projector-layout h2 { font-size: 2rem; margin: var(--space-5) 0 var(--space-4); }
.projector-layout p { color: var(--muted); }
.qr-timer { display: flex; gap: var(--space-4); align-items: center; margin: var(--space-5) 0; }
.qr-timer > span:first-child { font-size: 3rem; line-height: 1; min-width: 2ch; font-variant-numeric: tabular-nums; }
.qr-timer > span:last-child { max-width: 14ch; font-size: var(--text-sm); color: var(--muted); }
#qr-status { font-size: var(--text-base); min-height: 3.2em; }
.scan-placeholder { text-align: center; padding: var(--space-5) 0; color: var(--darkgreen); }
.scan-icon { display: block; font-size: 3rem; line-height: 1; margin-bottom: var(--space-4); }
.scan-placeholder p { margin-inline: auto; font-size: var(--text-sm); }
.scanner-panel { border-color: var(--control-border); }
.scanner-panel[data-state="success"] { border-color: var(--success-ink); }
.scanner-panel[data-state="error"] { border-color: var(--error-ink); }
video { width: 100%; aspect-ratio: 4/3; object-fit: cover; border-radius: var(--radius-sm); background: var(--ink); margin-bottom: var(--space-4); max-height: 400px; }
#scan-result { padding: var(--space-4) 0; font-size: var(--text-base); margin: 0; min-height: 5em; }
#scan-result[data-state="error"] { color: var(--error-ink); }
#scan-result[data-state="success"] { color: var(--success-ink); font-weight: 600; }
.spot-student { display: flex; gap: var(--space-5); align-items: center; padding: var(--space-4) 0; border-bottom: 1px solid var(--line); }
.spot-student:last-child { border: 0; }
.spot-number { color: var(--darkgreen); font-size: 1.5rem; font-variant-numeric: tabular-nums; }
.spot-student h2 { margin: 0; }
.spot-student p { margin: var(--space-1) 0 0; font-size: var(--text-sm); }
[hidden] { display: none !important; }

@media (hover: hover) {
  .button:hover:not(:disabled), .text-button:hover:not(:disabled) { background: var(--surface); border-color: var(--darkgreen); }
  .button.primary:hover:not(:disabled) { background: var(--green-hover); }
  a.lecture-card:hover { border-color: var(--darkgreen); }
  a.stat:hover { background: var(--surface); }
  .navigation > a:hover { color: var(--ink); border-bottom-color: var(--control-border); }
  a.text-link:hover, a.back:hover { text-decoration-thickness: 2px; }
}
@media (max-width: 960px) {
  .nav-role { display: none; }
  .stats { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .stat:nth-child(2) { border-right: 0; }
  .stat:nth-child(-n+2) { border-bottom: 1px solid var(--line); }
  .projector-layout { gap: var(--space-5); }
  .auth-layout { gap: var(--space-5); }
}
@media (max-width: 700px) {
  :root { --text-title: 1.75rem; }
  .topbar { padding: var(--space-2) var(--space-4); flex-wrap: wrap; gap: var(--space-2) var(--space-4); }
  .brand { font-size: 1.25rem; }
  .account { gap: var(--space-2); }
  .account-name { display: none; }
  .navigation { padding-inline: var(--space-4); gap: 0 var(--space-5); flex-wrap: wrap; }
  .container { padding: var(--space-5) var(--space-4) var(--space-6); }
  .page-heading { align-items: stretch; flex-direction: column; gap: var(--space-4); }
  .page-heading > .button { align-self: flex-start; }
  .stat { padding: var(--space-4); display: grid; grid-template-columns: minmax(0, 1fr) auto; align-items: center; gap: var(--space-2); }
  .stat small { display: none; }
  .stat > span > span { display: none; }
  .stat > strong { font-size: 1.5rem; }
  .section-heading { align-items: flex-start; flex-direction: column; gap: var(--space-3); }
  .lecture-grid, .window-grid, .approval, .projector-layout { grid-template-columns: minmax(0, 1fr); }
  .panel, .lecture-card { padding: var(--space-4); }
  .panel.compact { padding: var(--space-2) var(--space-4); }
  .approval { gap: var(--space-4); }
  .inline-form { flex-direction: column; align-items: stretch; }
  .inline-form .button { align-self: flex-start; }
  .auth-layout { display: flex; flex-direction: column; margin: 0; gap: var(--space-5); }
  .auth-intro { padding: 0; }
  .auth-intro .intro-steps { display: none; }
  .auth-panel { max-width: none; }
  .timeline > div { display: block; }
  .timeline time { display: block; margin-bottom: var(--space-2); }
  .projector h1, .projector-layout h2 { font-size: 1.75rem; }
  .projector .qr-image { max-width: 560px; width: 100%; justify-self: center; }
  .scanner-panel .actions { flex-direction: column; align-items: stretch; }
  .scanner-panel .actions .button { width: 100%; }
  footer { padding: var(--space-4); }
  footer span:last-child { display: none; }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation: none !important; transition: none !important; scroll-behavior: auto !important; }
}