/* mcq — Tufte-inspired reading UI */

/* ===========================
   Colour tokens
   =========================== */
:root {
  --bg:      #fffff8;
  --bg-alt:  #f8f4eb;
  --text:    #111;
  --text-dim: #666;
  --text-lt: #999;
  --accent:  #a00000;
  --accent-h: #c00000;
  --border:  #ccc;
  --border-lt: #e0ddd1;
  --code-bg: #f0ede4;
  --green:   #4a7c40;
  --blue:    #3b5998;
  --error-bg: #fdf0f0;
  --error-border: #e8c4c4;
}

/* Dark theme — explicit toggle */
[data-theme="dark"] {
  --bg:      #1a1a1a;
  --bg-alt:  #242420;
  --text:    #d4d0c8;
  --text-dim: #999;
  --text-lt: #666;
  --accent:  #d44040;
  --accent-h: #e85050;
  --border:  #3a3a36;
  --border-lt: #2e2e2a;
  --code-bg: #2a2a24;
  --green:   #6aac58;
  --blue:    #5b89c8;
  --error-bg: #2a1a1a;
  --error-border: #4a2a2a;
}

/* Dark theme — system preference fallback */
@media (prefers-color-scheme: dark) {
  html:not([data-theme]) {
    --bg:      #1a1a1a;
    --bg-alt:  #242420;
    --text:    #d4d0c8;
    --text-dim: #999;
    --text-lt: #666;
    --accent:  #d44040;
    --accent-h: #e85050;
    --border:  #3a3a36;
    --border-lt: #2e2e2a;
    --code-bg: #2a2a24;
    --green:   #6aac58;
    --blue:    #5b89c8;
    --error-bg: #2a1a1a;
    --error-border: #4a2a2a;
  }
}

/* ===========================
   Reset
   =========================== */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { font-size: 16px; -webkit-font-smoothing: antialiased; }

/* ===========================
   Base — Tufte typography
   =========================== */
body {
  font-family: Georgia, "Palatino Linotype", Palatino, "Book Antiqua", serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
}
a { color: var(--accent); text-decoration: none; }
a:hover { color: var(--accent-h); text-decoration: underline; }
p { margin-bottom: 1rem; }
h1, h2, h3, h4 {
  font-weight: 400;
  font-style: italic;
  color: var(--text);
}
h2 { font-size: 1.625rem; margin-bottom: 0.25rem; }
code {
  font-family: Menlo, "DejaVu Sans Mono", Consolas, monospace;
  font-size: 0.8125rem;
  color: var(--text);
  background: var(--code-bg);
  padding: 0.125rem 0.375rem;
  border-radius: 2px;
}

/* ===========================
   Top navigation — minimal
   =========================== */
.topnav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 5%;
  height: 44px;
  background: var(--bg);
  border-bottom: 1px solid var(--border-lt);
}
.topnav-brand {
  font-size: 0.875rem;
  font-weight: 400;
  font-variant: small-caps;
  letter-spacing: 0.1em;
  color: var(--text);
  text-decoration: none;
}
.topnav-brand:hover { color: var(--accent); text-decoration: none; }
.topnav-right {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}
.topnav-user {
  font-size: 0.8125rem;
  color: var(--text-dim);
}
.theme-toggle {
  background: none;
  border: none;
  cursor: pointer;
  font-size: 1rem;
  padding: 0.25rem;
  line-height: 1;
  color: var(--text-dim);
}
.theme-toggle:hover {
  background: none;
  border: none;
  color: var(--text);
}

/* ===========================
   Page containers
   =========================== */
.page-container {
  width: 70%;
  max-width: 900px;
  margin: 0 auto;
  padding: 2rem 0;
}
.auth-container {
  max-width: 380px;
  margin: 6rem auto 2rem;
  padding: 0 1rem;
}

@media (max-width: 768px) {
  .page-container {
    width: auto;
    padding: 1.5rem 1rem;
  }
}

/* ===========================
   Auth pages
   =========================== */
.auth-header {
  text-align: center;
  margin-bottom: 2rem;
}
.auth-header .brand {
  font-size: 1.5rem;
  font-weight: 400;
  font-variant: small-caps;
  letter-spacing: 0.1em;
  color: var(--text);
}
.auth-header .tagline {
  font-size: 0.75rem;
  color: var(--text-lt);
  font-style: italic;
  margin-top: 0.25rem;
}

/* ===========================
   Cards
   =========================== */
.card {
  background: var(--bg);
  border: none;
  border-radius: 0;
  padding: 0;
  margin-bottom: 1rem;
}
.auth-container .card {
  background: var(--bg-alt);
  border: 1px solid var(--border-lt);
  border-radius: 4px;
  padding: 1.5rem;
}

/* ===========================
   Alerts
   =========================== */
.error {
  background: var(--error-bg);
  color: var(--accent);
  border: 1px solid var(--error-border);
  padding: 0.625rem 1rem;
  border-radius: 3px;
  margin-bottom: 1rem;
  font-size: 0.875rem;
}

/* ===========================
   Buttons
   =========================== */
button, .btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.375rem 1rem;
  font-size: 0.8125rem;
  font-weight: 400;
  font-family: inherit;
  border: 1px solid var(--border);
  border-radius: 3px;
  cursor: pointer;
  text-decoration: none;
  white-space: nowrap;
  transition: background 0.12s, border-color 0.12s;
  line-height: 1.4;
  background: var(--bg);
  color: var(--text);
}
button:hover, .btn:hover {
  background: var(--bg-alt);
  border-color: var(--text-lt);
  text-decoration: none;
  color: var(--text);
}
.btn-ghost {
  background: transparent;
  color: var(--text-dim);
  border-color: var(--border-lt);
}
.btn-ghost:hover {
  background: var(--bg-alt);
  color: var(--text);
  border-color: var(--border);
  text-decoration: none;
}
.btn-sm {
  padding: 0.1875rem 0.625rem;
  font-size: 0.75rem;
}
.btn-danger {
  color: var(--accent);
  border-color: var(--accent);
}
.btn-danger:hover {
  background: var(--accent);
  color: var(--bg);
}

/* ===========================
   Forms
   =========================== */
.form-group { margin-bottom: 1rem; }
.form-group label {
  display: block;
  font-size: 0.75rem;
  font-weight: 400;
  font-variant: small-caps;
  letter-spacing: 0.06em;
  color: var(--text-dim);
  margin-bottom: 0.375rem;
}
.form-group input {
  width: 100%;
  padding: 0.5rem 0.625rem;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 3px;
  color: var(--text);
  font-size: 0.9375rem;
  font-family: inherit;
  transition: border-color 0.12s;
  -webkit-appearance: none;
  appearance: none;
}
.form-group input:focus {
  outline: none;
  border-color: var(--text-dim);
}
.form-group input::placeholder { color: var(--border); }
.form-actions { margin-top: 0.5rem; }

/* ===========================
   Document list
   =========================== */
.doc-list {
  margin-top: 1.5rem;
  border-top: 1px solid var(--border-lt);
}
.doc-item {
  display: block;
  padding: 0.875rem 0;
  text-decoration: none;
  border-bottom: 1px solid var(--border-lt);
  transition: background 0.1s;
}
.doc-item:hover {
  background: var(--bg-alt);
  text-decoration: none;
  padding-left: 0.5rem;
  padding-right: 0.5rem;
  margin-left: -0.5rem;
  margin-right: -0.5rem;
}
.doc-item.doc-read {
  opacity: 0.5;
}
.doc-title {
  font-size: 1.0625rem;
  font-weight: 400;
  color: var(--text);
  margin-bottom: 0.125rem;
}
.doc-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  font-size: 0.75rem;
  color: var(--text-lt);
  font-style: italic;
}
.doc-badge {
  display: inline-block;
  padding: 0 0.375rem;
  border-radius: 2px;
  font-size: 0.625rem;
  font-weight: 400;
  font-style: normal;
  font-variant: small-caps;
  letter-spacing: 0.06em;
}
.doc-badge.unread {
  background: transparent;
  color: var(--accent);
}
.doc-badge.read {
  background: transparent;
  color: var(--green);
}

/* ===========================
   Read view — two-column layout
   =========================== */
.read-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 2rem 2rem 2rem 0;
}
.read-layout {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 2rem;
  align-items: start;
}
.read-main {
  max-width: 900px;
  min-width: 0;
}
.read-toc {
  position: sticky;
  top: 1rem;
  max-height: calc(100vh - 2rem);
  overflow-y: auto;
  padding: 0.5rem 0;
  font-size: 0.875rem;
  line-height: 1.5;
  border-right: 1px solid var(--border-lt);
  padding-right: 1rem;
}
.read-toc ul {
  list-style: none;
  padding: 0;
  margin: 0;
}
.read-toc li {
  margin-bottom: 0.25rem;
}
.read-toc a {
  color: var(--text-lt);
  text-decoration: none;
  display: block;
  padding: 0.125rem 0;
  transition: color 0.1s;
}
.read-toc a:hover {
  color: var(--text);
  text-decoration: none;
}
.read-toc a.toc-active {
  color: var(--accent);
}

@media (max-width: 900px) {
  .read-container {
    padding: 1.5rem 1rem;
  }
  .read-layout {
    grid-template-columns: 1fr;
  }
  .read-toc {
    position: static;
    max-height: none;
    border-right: none;
    border-bottom: 1px solid var(--border-lt);
    padding-right: 0;
    padding-bottom: 0.75rem;
    margin-bottom: 0.5rem;
  }
}

.read-header {
  margin-bottom: 1.5rem;
}
.read-header h2 {
  font-size: 2rem;
  font-style: italic;
  font-weight: 400;
  line-height: 1.3;
}
.read-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  font-size: 0.8125rem;
  color: var(--text-lt);
  font-style: italic;
  margin-top: 0.375rem;
  margin-bottom: 0.75rem;
}
.read-actions {
  display: flex;
  gap: 0.5rem;
}

/* ===========================
   Markdown body — Tufte prose
   =========================== */
.markdown-body {
  font-size: 1.0625rem;
  line-height: 1.8;
  padding-top: 0.5rem;
  border-top: 1px solid var(--border-lt);
}
.markdown-body h1 {
  font-size: 2rem;
  font-weight: 400;
  font-style: italic;
  margin: 2rem 0 0.75rem;
}
.markdown-body h2 {
  font-size: 1.5rem;
  font-weight: 400;
  font-style: italic;
  margin: 1.75rem 0 0.5rem;
}
.markdown-body h3 {
  font-size: 1.1875rem;
  font-weight: 400;
  font-style: italic;
  margin: 1.5rem 0 0.5rem;
}
.markdown-body h4 {
  font-size: 1.0625rem;
  font-weight: 400;
  font-style: italic;
  margin: 1.25rem 0 0.375rem;
}
.markdown-body p { margin-bottom: 1rem; }
.markdown-body ul, .markdown-body ol {
  margin-bottom: 1rem;
  padding-left: 1.5rem;
}
.markdown-body li {
  margin-bottom: 0.375rem;
}
.markdown-body pre {
  background: var(--code-bg);
  border: none;
  border-radius: 0;
  padding: 1rem 1.25rem;
  overflow-x: auto;
  margin: 1rem 0;
  font-size: 0.8125rem;
  line-height: 1.6;
}
.markdown-body pre code {
  background: none;
  padding: 0;
  font-size: inherit;
  color: var(--text);
}
.markdown-body blockquote {
  border-left: none;
  padding: 0;
  margin: 1rem 0 1rem 1.5rem;
  font-style: italic;
  color: var(--text-dim);
}
.markdown-body table {
  width: 100%;
  border-collapse: collapse;
  margin: 1rem 0;
  font-size: 0.875rem;
}
.markdown-body th, .markdown-body td {
  padding: 0.375rem 0.75rem;
  border-bottom: 1px solid var(--border-lt);
  text-align: left;
}
.markdown-body th {
  background: transparent;
  font-weight: 400;
  font-variant: small-caps;
  letter-spacing: 0.04em;
  border-bottom: 2px solid var(--border);
}
.markdown-body hr {
  border: none;
  border-top: 1px solid var(--border-lt);
  margin: 2rem 0;
}
.markdown-body a { color: var(--accent); }
.markdown-body a:hover { color: var(--accent-h); }
.markdown-body img {
  max-width: 100%;
  height: auto;
}
.markdown-body strong { font-weight: 700; }