*, *::before, *::after {
  box-sizing: border-box;
}

:root {
  --color-bg: #fafaf8;
  --color-text: #1a1a1a;
  --color-muted: #5c5c5c;
  --color-accent: #6b4e9b;
  --color-border: #e0ddd8;
  --font-sans: system-ui, -apple-system, sans-serif;
  --max-width: 860px;
}

html {
  background-color: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-sans);
  line-height: 1.6;
}

body {
  margin: 0;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

main {
  flex: 1;
  padding: 2rem 1rem;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  width: 100%;
}

a {
  color: var(--color-accent);
  text-decoration: underline;
}

a:hover {
  text-decoration: none;
}

/* Header */
header {
  border-bottom: 1px solid var(--color-border);
  padding: 1rem;
}

header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.5rem 1.5rem;
  padding-right: 3rem;
}

.site-name {
  font-weight: 700;
  font-size: 1.5rem;
  text-decoration: none;
  color: var(--color-text);
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
}


nav ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 1.25rem;
}

nav a {
  text-decoration: none;
  color: var(--color-muted);
  font-size: 0.95rem;
}

nav a:hover,
nav a[aria-current="page"] {
  color: var(--color-accent);
}

nav a[aria-current="page"] {
  font-weight: 600;
}

/* Footer */
footer {
  border-top: 1px solid var(--color-border);
  padding: 1.5rem 1rem;
  color: var(--color-muted);
  font-size: 0.875rem;
}

footer p {
  margin: 0;
}

/* Typography */
h1,
h2,
h3 {
  line-height: 1.2;
}

h1 {
  font-size: 2rem;
  margin-top: 0;
}

h2 {
  font-size: 1.5rem;
}

p {
  max-width: 65ch;
}

/* Home hero */
.hero {
  padding: 3rem 0 2rem;
}

.hero h1 {
  font-size: 2.5rem;
  margin-bottom: 0.5rem;
}

.hero-title {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.375rem 0.75rem;
}

.hero-intro {
  white-space: nowrap;
  font-size: clamp(2.5rem, 6.5vw, 4.3rem);
  font-weight: 900;
  line-height: 1;
}

.hero-wordmark {
  height: clamp(3rem, 8vw, 5rem);
  width: auto;
  max-width: 100%;
  vertical-align: middle;
}

.hero-photo {
  aspect-ratio: 1;
  width: clamp(4.75rem, 12vw, 6.5rem);
  height: clamp(4.75rem, 12vw, 6.5rem);
  border: 1px solid var(--color-border);
  border-radius: 50%;
  object-fit: cover;
  object-position: 54% 36%;
  box-shadow: 0 0.75rem 1.75rem rgba(26, 26, 26, 0.12);
}

.tagline {
  font-size: 1.15rem;
  color: var(--color-muted);
  max-width: 55ch;
  margin-top: 0;
}

section {
  margin-bottom: 2.5rem;
}

.quick-links ul {
  list-style: none;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.quick-links a {
  font-size: 1.05rem;
}

/* Project groups (projects page) */
/* Project group sections */
.project-group {
  margin-bottom: 2.5rem;
}

.project-group:last-child {
  margin-bottom: 0;
}

.group-heading {
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-muted);
  margin-bottom: 0.25rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--color-accent);
}


.project-filters {
  border: 1px solid var(--color-border);
  border-radius: 6px;
  background: #fff;
  margin: 1.5rem 0 2rem;
  padding: 1rem;
}

.project-filter-label {
  color: var(--color-muted);
  font-size: 0.9rem;
  font-weight: 600;
  margin: 0 0 0.65rem;
}

.project-filter-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.project-filter-button {
  border: 1px solid var(--color-border);
  border-radius: 999px;
  background: #fff;
  color: var(--color-text);
  cursor: pointer;
  font: inherit;
  font-size: 0.9rem;
  font-weight: 600;
  line-height: 1.2;
  min-height: 2.25rem;
  padding: 0.45rem 0.85rem;
}

.project-filter-button:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

.project-filter-button:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

.project-filter-button[aria-pressed="true"] {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: #fff;
}

.project-filter-summary,
.project-filter-empty {
  color: var(--color-muted);
  font-size: 0.875rem;
}

.project-filter-summary {
  margin: 0.75rem 0 0;
}

.project-filter-empty {
  margin: -1rem 0 2rem;
}

/* Card list */
.area-cards {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  margin-top: 0.75rem;
}

/* Individual expandable cards */
.area-card {
  border: 1px solid var(--color-border);
  border-radius: 6px;
  padding: 0;
  background: #fff;
}

.project-card summary {
  font-weight: 600;
  font-size: 1.1rem;
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.85rem 1rem;
  margin: 0;
  border-radius: 6px;
  transition: background 0.1s ease;
}

.project-card summary:hover {
  background: #f5f4f0;
}

.project-card summary::marker,
.project-card summary::-webkit-details-marker {
  display: none;
  content: "";
}

.project-card summary::before {
  content: "+";
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 1.25rem;
  height: 1.25rem;
  font-size: 1rem;
  font-weight: 400;
  line-height: 1;
  border-radius: 50%;
  border: 1px solid var(--color-border);
  color: var(--color-muted);
  flex-shrink: 0;
}

.project-card[open] summary::before {
  content: "\2013";
}

.project-card summary:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

.project-card-body {
  padding: 0 1rem 1rem 2.75rem;
}

.area-card p {
  margin-bottom: 0.5rem;
}

.area-card-note {
  font-size: 0.875rem;
  color: var(--color-muted);
}

/* Mathist Consulting intro (home page) */
.mathist-intro {
  border-top: 1px solid var(--color-border);
  padding-top: 2rem;
}

.mathist-link a {
  font-size: 1.05rem;
  font-weight: 600;
}

/* Public welcome letter */
.letter-page {
  border: 1px solid var(--color-border);
  border-radius: 6px;
  background: #fff;
  padding: clamp(1.25rem, 4vw, 2.5rem);
}

.letter-kicker {
  color: var(--color-muted);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  margin: 0 0 0.5rem;
  text-transform: uppercase;
}

.letter-page h1 {
  margin-bottom: 1.25rem;
}

.letter-page h2 {
  margin-top: 2rem;
}

.link-list {
  padding-left: 1.25rem;
}

.link-list li {
  margin-bottom: 0.35rem;
}

.letter-signoff {
  color: var(--color-muted);
  font-weight: 600;
  margin-top: 2rem;
}

/* Contact form */
.contact-links {
  padding-left: 1.25rem;
}

.privacy-note,
.field-help {
  color: var(--color-muted);
  font-size: 0.95rem;
}

.contact-form,
.status-panel {
  max-width: 720px;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  background: #fff;
  padding: 1.25rem;
}

.form-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
}

.form-field {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  margin-bottom: 1rem;
}

.form-field label,
.checkbox-field label {
  font-weight: 600;
}

.form-field label span {
  color: var(--color-muted);
  font-size: 0.85rem;
  font-weight: 500;
}

.form-field input,
.form-field select,
.form-field textarea {
  width: 100%;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  color: var(--color-text);
  font: inherit;
  padding: 0.65rem 0.75rem;
}

.form-field textarea {
  min-height: 11rem;
  resize: vertical;
}

.form-field input:focus,
.form-field select:focus,
.form-field textarea:focus {
  border-color: var(--color-accent);
  outline: 2px solid color-mix(in srgb, var(--color-accent) 25%, transparent);
  outline-offset: 2px;
}

.honeypot {
  position: absolute;
  left: -9999px;
}

.form-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  align-items: center;
  margin: 1rem 0 0;
}

.button {
  border: 1px solid var(--color-accent);
  border-radius: 6px;
  background: var(--color-accent);
  color: #fff;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font: inherit;
  font-weight: 600;
  min-height: 2.75rem;
  padding: 0.65rem 1rem;
  text-decoration: none;
}

.button:hover {
  text-decoration: none;
}

.button-secondary {
  background: #fff;
  color: var(--color-accent);
}

.form-error-message {
  border-left: 4px solid #b3261e;
  color: #7f1d1d;
  background: #fff4f2;
  padding: 0.75rem 1rem;
}

.status-panel-success {
  border-color: #8eb897;
}

.status-panel-error {
  border-color: #d9a19a;
}

@media (max-width: 720px) {
  main {
    padding-top: 1.25rem;
  }

  .hero {
    padding: 2rem 0 1rem;
  }
}

@media (max-width: 640px) {
  header .container {
    padding-right: 0;
  }

  nav ul,
  .form-grid {
    flex-wrap: wrap;
    grid-template-columns: 1fr;
  }
}

@media (max-width: 520px) {
  .hero-title {
    align-items: flex-start;
    flex-direction: column;
  }

  .hero-wordmark {
    height: auto;
    max-height: 4rem;
  }
}


/* Calendar events */
.event-panel {
  border: 1px solid var(--color-border);
  border-radius: 6px;
  background: #fff;
  margin: 1.5rem 0 2rem;
  padding: 1rem;
}

.event-panel-heading,
.admin-header,
.admin-actions {
  align-items: center;
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  justify-content: space-between;
}

.keyword-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.keyword-button,
.keyword-pill,
.primary-button,
.text-button {
  border: 1px solid var(--color-border);
  border-radius: 999px;
  font: inherit;
  font-size: 0.9rem;
  line-height: 1.2;
  min-height: 2.25rem;
  padding: 0.45rem 0.85rem;
}

.keyword-button,
.primary-button,
.text-button {
  cursor: pointer;
}

.keyword-button,
.text-button {
  background: #fff;
  color: var(--color-text);
}

.keyword-button:hover,
.text-button:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

.keyword-button[aria-pressed="true"],
.primary-button {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: #fff;
}

.keyword-pill {
  background: #f2eff6;
  color: var(--color-accent);
  display: inline-flex;
}

.event-status,
.muted-small,
.event-meta,
.event-date {
  color: var(--color-muted);
}

.event-status,
.muted-small {
  font-size: 0.92rem;
}

.event-list {
  display: grid;
  gap: 0.85rem;
}

.event-item {
  border-bottom: 1px solid var(--color-border);
  padding: 1rem 0;
}

.event-item h3 {
  margin: 0.2rem 0;
}

.event-date {
  font-size: 0.9rem;
  font-weight: 700;
}

.event-keywords {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.event-keywords span {
  color: var(--color-muted);
  font-size: 0.85rem;
}

.event-cancelled {
  color: #9b2f2f;
  font-size: 0.85rem;
  margin-left: 0.25rem;
}

.admin-shell {
  max-width: 980px;
}

.admin-form,
.keyword-admin {
  display: grid;
  gap: 0.9rem;
}

.admin-form label,
.keyword-admin label {
  display: grid;
  font-weight: 600;
  gap: 0.35rem;
}

.admin-form input,
.admin-form textarea,
.admin-form select,
.keyword-admin input {
  border: 1px solid var(--color-border);
  border-radius: 6px;
  font: inherit;
  padding: 0.65rem 0.75rem;
  width: 100%;
}

.admin-grid {
  display: grid;
  gap: 0.9rem;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.admin-note,
.admin-warning {
  font-size: 0.92rem;
  margin: 0.25rem 0 1rem;
}

.admin-note {
  color: var(--color-muted);
}

.admin-warning {
  background: #fff7e8;
  border: 1px solid #e8c78f;
  border-radius: 6px;
  color: #62420c;
  padding: 0.75rem 0.9rem;
}

.admin-checkbox {
  align-items: center;
  color: var(--color-muted);
  display: inline-flex;
  font-weight: 500;
  gap: 0.5rem;
  min-height: 2.8rem;
}

.admin-checkbox input {
  width: auto;
}

@media (max-width: 680px) {
  .admin-grid {
    grid-template-columns: 1fr;
  }
}


.visually-hidden {
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  height: 1px;
  overflow: hidden;
  position: absolute;
  white-space: nowrap;
  width: 1px;
}

.event-list.area-cards {
  margin-top: 0.75rem;
}

.event-item {
  background: #fff;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  padding: 0;
}

.event-card-body,
.admin-event-list .event-item {
  padding: 1rem;
}

.event-item p {
  margin: 0.45rem 0;
}

.event-keywords {
  margin-top: 0.75rem;
}

.event-keywords span {
  background: #f2eff6;
  border: 1px solid var(--color-border);
  border-radius: 999px;
  color: var(--color-accent);
  display: inline-flex;
  font-size: 0.85rem;
  font-weight: 600;
  line-height: 1.2;
  min-height: 1.9rem;
  padding: 0.35rem 0.7rem;
}

.keyword-admin + .keyword-list {
  margin-top: 1rem;
}

.admin-editor[hidden],
[data-event-list-panel][hidden],
[data-series-list-panel][hidden],
[data-blackout-list-panel][hidden] {
  display: none;
}