@font-face {
  font-family:'Iansui Chalk';
  src:url('assets/iansui-chalk.woff') format('woff');
  font-style:normal;
  font-weight:400;
  font-display:swap
}
:root {
  --white:#f7f5dc;
  --yellow:#ffe594;
  --green:#b9e5a6;
  --red:#ffaaa6;
  --muted:#b6c9bc;
  --ink:#173b30;
  --font:'Iansui Chalk','DFKai-SB','BiauKai','Noto Sans TC',sans-serif;
  color-scheme:dark
}
* {
  box-sizing:border-box
}
html {
  scroll-behavior:smooth
}
body {
  margin:0;
  background:#d8bd91;
  color:var(--white);
  font-family:var(--font);
  font-size:18px;
  line-height:1.65
}
button,input {
  font:inherit
}
a {
  color:inherit;
  text-decoration:none
}
button {
  cursor:pointer
}
button:focus-visible,a:focus-visible {
  outline:3px dashed var(--yellow);
  outline-offset:4px
}
::selection {
  background:var(--yellow);
  color:var(--ink)
}
.wall {
  min-height:100vh;
  padding:18px clamp(12px,2.8vw,42px) 24px;
  background:radial-gradient(circle at 12% 5%,#f3dcb0 0,transparent 30%),radial-gradient(circle at 85% 100%,#b99969 0,transparent 35%),repeating-linear-gradient(95deg,#d6ba8d 0 26px,#d3b587 27px 28px)
}
.class-header {
  max-width:1480px;
  margin:0 auto 17px;
  display:flex;
  align-items:center;
  gap:24px;
  color:#254539
}
.wordmark {
  display:flex;
  align-items:center;
  gap:11px;
  font-size:24px;
  font-weight:700;
  line-height:1
}
.wordmark small {
  font-size:18px;
  display:block;
  margin-top:4px
}
.school-badge {
  background:#2c6550;
  border:3px solid #f5e1b8;
  color:#fff7df;
  border-radius:50%;
  width:47px;
  height:47px;
  display:grid;
  place-items:center;
  box-shadow:2px 3px 0 #8c6b43;
  position:relative
}
.school-badge span {
  font-size:10px;
  position:absolute;
  right:5px;
  top:4px;
  color:#ffe799
}
.header-note {
  margin-left:auto;
  font-size:17px
}
.repo-link {
  border:2px solid #2c6550;
  border-radius:22px;
  padding:5px 15px;
  font-size:16px;
  white-space:nowrap
}
.repo-link:hover {
  background:#2c6550;
  color:#fff
}
.board-frame {
  max-width:1480px;
  margin:auto;
  background:linear-gradient(135deg,#8a4c29,#c7874c 12%,#8e542e 25%,#aa693c 80%,#7c4528);
  border:12px solid #9d6039;
  border-radius:9px;
  box-shadow:0 6px 0 #663921,0 20px 38px #5f45265e,inset 0 0 0 2px #dca56a
}
.board {
  position:relative;
  min-height:690px;
  padding:22px clamp(20px,4vw,64px) 60px;
  background:radial-gradient(circle at 50% 50%,#285044 0,#1d4035 68%,#16372f 100%);
  box-shadow:inset 0 0 28px 6px #0b2c24aa;
  overflow:hidden
}
.board:before {
  content:'';
  pointer-events:none;
  position:absolute;
  inset:0;
  opacity:.22;
  background-image:repeating-linear-gradient(2deg,transparent 0 4px,#c9e9d40a 5px 6px),radial-gradient(#e5ffea22 .45px,transparent .6px);
  background-size:auto,4px 4px
}
.board>* {
  position:relative
}
.board-top {
  display:flex;
  justify-content:space-between;
  gap:20px;
  color:#c4d5bd;
  border-bottom:1px dashed #85a390a8;
  padding-bottom:8px;
  font-size:13px;
  letter-spacing:.06em
}
.lesson-nav {
  display:flex;
  gap:8px;
  overflow-x:auto;
  padding:20px 1px 17px;
  scrollbar-color:#a4bda2 transparent
}
.lesson-tab {
  white-space:nowrap;
  min-height:41px;
  padding:5px 15px;
  border:1.5px solid #b8cfb793;
  border-radius:100px;
  font-size:16px;
  color:#d2decd;
  transition:.18s background,.18s transform
}
.lesson-tab b {
  color:var(--yellow);
  font-weight:400
}
.lesson-tab.current,.lesson-tab:hover {
  background:#f6f3de;
  color:#1c4a39;
  border-color:#f6f3de;
  transform:translateY(-2px)
}
.lesson-tab.current b,.lesson-tab:hover b {
  color:#8e5735
}
#lesson {
  max-width:1230px;
  margin:0 auto;
  outline:none;
  padding:10px 0 30px;
  min-height:520px
}
.loading,.no-script {
  text-align:center;
  padding:90px 0;
  color:var(--yellow)
}
.no-script {
  padding:15px
}
.no-script a {
  text-decoration:underline
}
.lesson-head {
  display:flex;
  justify-content:space-between;
  align-items:flex-start;
  gap:20px;
  margin:4px 0 26px
}
.kicker {
  font-size:15px;
  color:var(--yellow);
  letter-spacing:.08em;
  margin:0 0 7px
}
.lesson-head h1 {
  font-size:clamp(31px,3.7vw,53px);
  font-weight:400;
  line-height:1.25;
  margin:0;
  letter-spacing:.02em;
  text-shadow:1px 1px 1px #ffffff3b
}
.lesson-head h1 .yellow,.yellow-text {
  color:var(--yellow)
}
.green-text {
  color:var(--green)
}
.red-text {
  color:var(--red)
}
.white-text {
  color:var(--white)
}
.head-scribble {
  font-size:clamp(30px,6vw,75px);
  color:#b4d8ac91;
  transform:rotate(-12deg);
  line-height:1
}
.lead {
  font-size:clamp(18px,1.7vw,22px);
  line-height:1.85;
  color:#e1e9d8;
  margin:0 0 26px;
  max-width:1020px
}
.lead strong {
  font-weight:400;
  color:var(--yellow)
}
.chalk-line {
  height:2px;
  background:repeating-linear-gradient(90deg,#c8e1c8a6 0 13px,transparent 14px 19px);
  margin:26px 0
}
.two-col {
  display:grid;
  grid-template-columns:minmax(0,1fr) minmax(0,1fr);
  gap:clamp(18px,3vw,46px)
}
.three-col {
  display:grid;
  grid-template-columns:repeat(3,minmax(0,1fr));
  gap:16px
}
.chalk-card {
  border:2px solid #d1e0c6b8;
  border-radius:5px;
  padding:20px 23px;
  background:#1a423738;
  box-shadow:inset 0 0 0 1px #ffffff1c;
  transform:rotate(-.3deg)
}
.chalk-card:nth-child(even) {
  transform:rotate(.4deg)
}
.chalk-card.yellow {
  border-color:#f6dc92
}
.chalk-card.green {
  border-color:#bce7b2
}
.chalk-card.red {
  border-color:#f4a6a2
}
.chalk-card h2,.chalk-card h3 {
  font-weight:400;
  font-size:25px;
  margin:0 0 10px;
  color:var(--yellow)
}
.chalk-card h3 {
  font-size:22px
}
.chalk-card.green h2,.chalk-card.green h3 {
  color:var(--green)
}
.chalk-card.red h2,.chalk-card.red h3 {
  color:var(--red)
}
.chalk-card p {
  margin:0 0 12px;
  color:#e5e9d7
}
.chalk-card p:last-child {
  margin-bottom:0
}
.chalk-card small {
  font-size:15px;
  color:#bccfc0
}
.card-icon {
  font-size:36px;
  display:block;
  margin-bottom:5px;
  color:#f6e1a1
}
.chalk-list {
  margin:0;
  padding-left:23px
}
.chalk-list li {
  margin:8px 0
}
.role-arrow {
  text-align:center;
  color:var(--green);
  font-size:25px;
  margin:14px 0
}
.mini-label {
  font-size:14px;
  letter-spacing:.1em;
  color:var(--yellow);
  margin:0 0 8px
}
.question {
  border-left:4px solid var(--yellow);
  padding:5px 0 8px 20px;
  margin:28px 0 18px
}
.question h2 {
  font-size:24px;
  font-weight:400;
  color:var(--yellow);
  margin:0 0 6px
}
.question p {
  margin:0;
  color:#e4e9d9
}
.options {
  display:flex;
  flex-wrap:wrap;
  gap:10px
}
.chalk-button {
  display:inline-flex;
  align-items:center;
  justify-content:center;
  min-height:45px;
  gap:8px;
  padding:6px 20px;
  border:2px solid #e5efd9;
  border-radius:4px;
  color:var(--white);
  background:transparent;
  font-size:18px;
  text-align:center;
  box-shadow:2px 2px 0 #081e19a9;
  transition:.15s transform,.15s background
}
.chalk-button:hover {
  transform:translateY(-2px);
  background:#e5efd920
}
.chalk-button.primary {
  color:#193c30;
  background:var(--yellow);
  border-color:var(--yellow)
}
.chalk-button.primary:hover {
  background:#fff0b7
}
.chalk-button.small {
  min-height:37px;
  font-size:16px;
  padding:4px 12px
}
.answer-slot {
  min-height:12px;
  margin-top:18px
}
.feedback {
  border:2px dashed var(--green);
  padding:16px 20px;
  color:var(--green);
  background:#14372bb0
}
.feedback.bad {
  border-color:var(--red);
  color:var(--red)
}
.feedback strong {
  display:block;
  font-size:23px;
  font-weight:400
}
.feedback p {
  color:var(--white);
  margin:5px 0 12px
}
.feedback a {
  border-bottom:1px dashed currentColor
}
.lesson-actions {
  display:flex;
  justify-content:space-between;
  gap:14px;
  margin-top:30px;
  align-items:center
}
.lesson-actions .chalk-button {
  min-width:130px
}
.side-note {
  color:#c8ddc9;
  font-size:16px
}
.goal-strip {
  display:flex;
  align-items:stretch;
  gap:12px
}
.goal-strip>.chalk-card {
  flex:1
}
.goal-strip .join {
  color:var(--yellow);
  font-size:30px;
  align-self:center
}
.sample-goal {
  padding:19px 23px;
  border:2px dashed var(--green);
  border-radius:5px;
  font-size:20px;
  line-height:1.9;
  color:#e6f1de;
  margin:24px 0
}
.sample-goal .pill {
  color:var(--ink);
  background:var(--green);
  font-size:14px;
  padding:3px 10px;
  border-radius:15px;
  margin-right:10px
}
.bad-goal {
  color:var(--red);
  text-decoration:line-through;
  text-decoration-thickness:1px
}
.ticket-layout {
  display:grid;
  grid-template-columns:minmax(0,1.15fr) minmax(260px,.85fr);
  gap:24px
}
.code-board {
  border:2px solid #c4d5bb;
  background:#143529a8;
  padding:20px 22px;
  font:18px/1.85 var(--font);
  white-space:pre-wrap;
  overflow-wrap:anywhere;
  color:var(--white);
  margin:0
}
.code-board .yellow-text,.code-board .green-text {
  font-weight:400
}
.stepper {
  display:flex;
  gap:8px;
  flex-wrap:wrap;
  margin-bottom:15px
}
.stepper span {
  padding:4px 11px;
  border:1px dashed #b5c7b6;
  color:#c4dac2;
  border-radius:3px;
  font-size:16px
}
.status-chip {
  display:inline-block;
  padding:3px 13px;
  border:2px solid currentColor;
  transform:rotate(-3deg);
  margin-bottom:13px
}
.status-open {
  color:var(--yellow)
}
.status-doing {
  color:var(--green)
}
.status-done {
  color:var(--white)
}
.simulation {
  min-height:254px;
  border:2px dashed #d7e9cc8a;
  padding:19px 22px
}
.simulation h3 {
  font-size:24px;
  font-weight:400;
  margin:0 0 8px
}
.simulation p {
  margin:0 0 15px
}
.simulation .muted {
  color:#c0d3c0;
  font-size:16px
}
.flow-grid {
  display:grid;
  grid-template-columns:repeat(4,minmax(0,1fr));
  gap:10px
}
.flow-box {
  border:2px solid #cee3c8;
  padding:17px;
  min-height:155px
}
.flow-box .num {
  font-size:28px;
  color:var(--yellow)
}
.flow-box h3 {
  font-weight:400;
  font-size:23px;
  margin:6px 0
}
.flow-box p {
  font-size:16px;
  margin:0;
  color:#d2e0cf
}
.flow-box:nth-child(2) {
  border-color:var(--green)
}
.flow-box:nth-child(3) {
  border-color:var(--red)
}
.flow-box:nth-child(4) {
  border-color:var(--yellow)
}
.highlight {
  color:var(--yellow)
}
.command {
  font-size:17px;
  line-height:1.6;
  display:block;
  background:#143529;
  border:1.5px dashed #bdcebc;
  padding:13px 17px;
  margin:14px 0;
  overflow-wrap:anywhere;
  white-space:pre-wrap;
  color:#dff1d7
}
.small-print {
  font-size:15px;
  color:#bfd4bf
}
.numbered {
  counter-reset:item;
  list-style:none;
  padding:0;
  margin:0
}
.numbered li {
  display:flex;
  gap:14px;
  margin:10px 0
}
.numbered li:before {
  counter-increment:item;
  content:counter(item);
  border:1px solid var(--yellow);
  color:var(--yellow);
  height:28px;
  min-width:28px;
  text-align:center;
  line-height:25px;
  border-radius:50%
}
.cta-bar {
  border:2px solid var(--yellow);
  padding:16px 21px;
  display:flex;
  justify-content:space-between;
  gap:15px;
  align-items:center;
  margin-top:23px
}
.cta-bar strong {
  font-size:22px;
  color:var(--yellow);
  font-weight:400
}
.cta-bar p {
  font-size:16px;
  margin:0;
  color:#dce6d5
}
.chalk-tray {
  position:absolute;
  bottom:7px;
  left:18px;
  right:18px;
  height:24px;
  border-top:2px solid #c4b184aa;
  display:flex;
  gap:13px;
  align-items:center;
  padding-left:23px
}
.chalk-piece {
  width:43px;
  height:9px;
  border-radius:7px;
  display:inline-block;
  box-shadow:1px 3px 2px #091e17
}
.chalk-piece.white {
  background:#e9eddf
}
.chalk-piece.yellow {
  background:var(--yellow);
  transform:rotate(-6deg)
}
.chalk-piece.green {
  background:var(--green);
  transform:rotate(4deg)
}
.chalk-piece.red {
  background:var(--red);
  transform:rotate(-4deg)
}
.eraser {
  margin-left:auto;
  width:70px;
  height:19px;
  background:#ad7a55;
  border-radius:3px 3px 8px 8px;
  box-shadow:inset 0 -5px #544b45
}
.class-footer {
  max-width:1480px;
  margin:16px auto 0;
  display:flex;
  justify-content:space-between;
  gap:20px;
  color:#315346;
  font-size:15px
}
@media(max-width:1000px) {
  .three-col,.flow-grid {
    grid-template-columns:repeat(2,minmax(0,1fr))
  }
  .goal-strip {
    flex-wrap:wrap
  }
  .goal-strip .join {
    display:none
  }
  .goal-strip>.chalk-card {
    flex:1 1 44%
  }
  .ticket-layout {
    grid-template-columns:1fr
  }
  .header-note {
    display:none
  }
}
@media(max-width:700px) {
  body {
    font-size:17px
  }
  .wall {
    padding:8px 8px 20px
  }
  .class-header {
    margin:4px 9px 12px
  }
  .wordmark {
    font-size:19px
  }
  .wordmark small {
    font-size:15px
  }
  .school-badge {
    height:39px;
    width:39px
  }
  .repo-link {
    margin-left:auto;
    font-size:13px;
    padding:4px 9px
  }
  .board-frame {
    border-width:7px
  }
  .board {
    padding:14px 17px 48px;
    min-height:700px
  }
  .board-top {
    font-size:11px
  }
  .board-top span:last-child {
    display:none
  }
  .lesson-nav {
    margin:0 -3px;
    gap:5px;
    padding:16px 2px
  }
  .lesson-tab {
    font-size:14px;
    padding:4px 11px;
    min-height:38px
  }
  .lesson-head {
    margin:4px 0 20px
  }
  .head-scribble {
    display:none
  }
  .lead {
    font-size:17px
  }
  .two-col,.three-col,.flow-grid {
    grid-template-columns:1fr
  }
  .chalk-card {
    padding:15px 18px
  }
  .chalk-card h2 {
    font-size:22px
  }
  .goal-strip>.chalk-card {
    flex-basis:100%
  }
  .code-board {
    font-size:16px;
    padding:14px
  }
  .lesson-actions {
    align-items:stretch
  }
  .lesson-actions .chalk-button {
    min-width:0
  }
  .lesson-actions .side-note {
    display:none
  }
  .cta-bar {
    display:block
  }
  .cta-bar .chalk-button {
    margin-top:12px
  }
  .class-footer {
    display:block;
    text-align:center;
    font-size:13px
  }
  .class-footer span {
    display:block;
    margin:5px
  }
  .chalk-tray {
    height:17px
  }
  .eraser {
    height:15px
  }
}
@media(prefers-reduced-motion:reduce) {
  html {
    scroll-behavior:auto
  }
  .lesson-tab,.chalk-button {
    transition:none
  }
}