@import url("https://cdn.jsdelivr.net/gh/jwarby/pygments-css@master/github.css");
:root {
  --bg-white: #f9f7f2;
  --primary-color: #4287f5;
  --secondary-color: #2c3e50;
  --text-color: #333;

  --bg-white-half: #fcfbf6;
  /*https://www.realtimecolors.com/?colors=333333-f9f7f2-4287f5-2c3e50-00a9ff&fonts=Inter-Inter*/
}

.primary-color {
  color: var(--primary-color);
}
.secondary-color {
  color: var(--secondary-color);
}

html {
  min-height: 100%;
  min-width: 100%;
  -webkit-background-size: cover;
  -moz-background-size: cover;
  -o-background-size: cover;
  background-size: cover;
  scroll-behavior: smooth;
}

body {
  font-family: "Helvetica", sans-serif;
  line-height: 1.6;
  color: var(--text-color);
  margin: 0;
  padding: 0;
  background-color: var(--bg-white);
  transition: all 0.2s ease;
}
textarea {
  font-family: "Helvetica", sans-serif;
  color: var(--text-color);
  background-color: var(--bg-white);
  width: 100%;
  display: inline-block;
  border: 1px solid var(--text-color);
  border-radius: 4px;
  box-sizing: border-box;
  line-height: 1.25em;
  min-height: 5em;
}
blockquote {
  border-left: 4px solid #ccc;
  margin: 1rem 0;
  padding-left: 1rem;
  color: #555;
  font-style: italic;
}

input[type="text"],
input[type="password"],
select {
  width: 100%;
  padding: 12px 20px;
  margin: 8px 0;
  display: inline-block;
  border: 1px solid var(--text-color);
  background-color: var(--bg-white);
  color: var(--text-color);
  font-family: "Helvetica", sans-serif;

  border-radius: 4px;
  box-sizing: border-box;
}

/* .container textarea {
  display: inline-block;
  margin: 0 auto;
} */

.w800 {
  width: 800px;
}

.no-cursor {
  cursor: none;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 40px;
}

.hstack {
  display: flex;
  flex-direction: row;
  align-items: center;
  gap: 1rem;
}
.vstack {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
}

.serif {
  font-family: "Rosart", serif;
}

.mono {
  font-family: "PitchSans", "Courier New", monospace;
}

code {
  font-family: "Source Code Pro", monospace;
}

input {
  font-family: "Helvetica", sans-serif;
  color: var(--text-color);
  background-color: var(--bg-white);
  border: 1px;
}

h1,
h2 {
  text-align: center;
}

h3,
h4,
h5,
h6 {
  text-align: left;
}

h1 {
  font-weight: 600;
  font-size: 5.3rem;
  font-family: "Helvetica", sans-serif;
  letter-spacing: -2;
  line-height: 1.15;
}

h1 .normal {
  font-weight: 400;
  font-size: 3.5rem;
  font-family: "Helvetica", sans-serif;
  letter-spacing: normal;
}
/* 
table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 20px;
  background-color: var(--bg-white);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

th,
td {
  border: 1px solid #ddd;
  padding: 8px;
  text-align: left;
  font-size: 12px;
}

th {
  background-color: var(--bg-white);
  font-weight: 500;
  color: var(--secondary-color);
  font-family: "Pitch Sans", Courier, monospace;
  font-size: 16px;
  text-transform: uppercase;
  text-align: center;
}

tbody td {
  height: 30px;
  font-weight: 400;
  cursor: pointer;
}

tbody td:hover {
  background-color: var(--bg-white);
} */

form {
  width: 80%;
}
button,
input[type="submit"] {
  display: inline-block;
  padding: 10px 20px;
  border: 1px solid black;
  background-color: white;
  color: black;
  cursor: pointer;
  transition: all 0.3s;
  font-family: Courier, monospace;
  font-weight: 500;
  font-size: 16px;
  text-transform: uppercase;
  border-radius: 999px;
}

button:hover {
  background-color: var(--primary-color);
  border-color: var(--primary-color);
  color: var(--bg-white);
}

input[type="submit"]:hover {
  background-color: var(--secondary-color);
  border-color: var(--secondary-color);
  color: var(--bg-white);
}

a:visited {
  color: inherit;
}

iframe {
  border: none;
}

.hidden,
.hide {
  display: none;
}

@media (max-width: 767px) {
  th,
  td {
    font-size: 10px;
    padding: 6px;
  }

  h1 {
    font-size: 24px;
  }
}

@media (max-width: 480px) {
  th,
  td {
    font-size: 9px;
    padding: 4px;
  }

  h1 {
    font-size: 20px;
  }
}

@media (max-width: 320px) {
  th,
  td {
    font-size: 8px;
    padding: 2px;
  }

  h1 {
    font-size: 18px;
  }
  .container {
    padding: 5px;
  }
}

/* Adaptive take up space within a stack, used for content or for pushing items. */
.spacer {
  flex: 1;
}

div.center {
  max-width: 650px;
  text-align: left;
  margin: auto;
}
div.center ol,
div.center ul {
  text-align: left;
}
.lesson-link {
  align-items: flex-start;
}
/* Lessons list */
ul.lessons-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.lesson-item {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 14px 0;
  border: 1px solid #123;
  border-radius: 24px;
  padding: 24px;
}

.lesson-link {
  display: flex;
  gap: 12px;
  text-decoration: none;
  color: inherit;
}

.lesson-thumb {
  width: 96px;
  height: 96px;
  border-radius: 8px;
  object-fit: cover;
  background: #eee;
  flex-shrink: 0;
}

.lesson-text {
  display: flex;
  flex-direction: column;
  padding-left: 10px;
  margin-top: -4px;
}

.lesson-title {
  font-weight: 600;
  margin: 0;
}

.lesson-subtitle {
  margin-top: 2px;
  color: #555;
  font-size: 0.95em;
}

.coming-soon {
  opacity: 0.8;
}

/* MathJax (CHTML) responsive sizing and layout */
/* Base: inherit surrounding text size; ensure long display equations can scroll on small screens */
mjx-container[jax="CHTML"][display="true"] {
  overflow-x: auto;
  overflow-y: hidden;
}

/* Slightly increase math size on smaller screens for readability */
@media (max-width: 800px) {
  mjx-container[jax="CHTML"] {
    font-size: 18px !important; /* ~1.125em for inline math */
  }
  mjx-container[jax="CHTML"][display="true"] {
    font-size: 18px !important; /* a bit larger for display math */
  }
}

@media (max-width: 480px) {
  mjx-container[jax="CHTML"] {
    font-size: 18px !important;
  }
  mjx-container[jax="CHTML"][display="true"] {
    font-size: 18px !important;
  }
}