:root {
  color-scheme: light;
  --ink: #1b2333;
  --muted: #5d6678;
  --paper: #f6f8fb;
  --surface: #ffffff;
  --line: #dbe2ec;
  --red: #b1040e;
  --red-dark: #820000;
  --teal: #007c89;
  --gold: #c69214;
  --plum: #6a4c93;
  --shadow: 0 18px 50px rgba(27, 35, 51, 0.13);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.55;
}

a {
  color: inherit;
}

img {
  display: block;
  max-width: 100%;
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: 0.75rem;
  z-index: 30;
  padding: 0.5rem 0.75rem;
  color: #ffffff;
  background: var(--red-dark);
  transform: translateY(-160%);
}

.skip-link:focus {
  transform: translateY(0);
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 68px;
  padding: 0 5vw;
  color: var(--ink);
  background: rgba(246, 248, 251, 0.92);
  border-bottom: 1px solid rgba(219, 226, 236, 0.85);
  backdrop-filter: blur(16px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
  font-weight: 800;
  text-decoration: none;
}

.brand-mark {
  display: grid;
  width: 42px;
  height: 42px;
  place-items: center;
  color: #ffffff;
  background: var(--red);
  border-radius: 8px;
  box-shadow: 0 10px 22px rgba(177, 4, 14, 0.22);
}

.brand-text {
  font-size: 1.05rem;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 1.1rem;
  color: var(--muted);
  font-size: 0.95rem;
  font-weight: 700;
}

.site-nav a {
  text-decoration: none;
}

.site-nav a:hover,
.site-nav a:focus-visible {
  color: var(--red);
}

.hero {
  position: relative;
  display: grid;
  min-height: 68svh;
  overflow: hidden;
  color: #ffffff;
  background: #152033 url("../Notes/18-IceCreamStore.assets/image-20240530213214062.png") center / cover no-repeat;
}

.hero::before {
  position: absolute;
  inset: 0;
  content: "";
  background: rgba(8, 16, 30, 0.68);
}

.hero-backdrop {
  position: absolute;
  inset: auto 5vw 3rem auto;
  width: min(46vw, 540px);
  height: min(32vw, 360px);
  background:
    url("../Notes/lec8.assets/heap1.png") center / cover no-repeat,
    #ffffff;
  border: 1px solid rgba(255, 255, 255, 0.28);
  border-radius: 8px;
  box-shadow: var(--shadow);
  filter: brightness(1.8) contrast(1.12);
  opacity: 0.96;
}

.hero-inner {
  position: relative;
  z-index: 1;
  width: min(1120px, 90vw);
  margin: 0 auto;
  padding: 7rem 0 5rem;
}

.eyebrow {
  margin: 0 0 0.75rem;
  color: var(--gold);
  font-size: 0.78rem;
  font-weight: 900;
  letter-spacing: 0;
  text-transform: uppercase;
}

.hero h1 {
  max-width: 820px;
  margin: 0;
  font-size: clamp(3rem, 9vw, 7.8rem);
  line-height: 0.95;
  letter-spacing: 0;
}

.hero-copy {
  max-width: 680px;
  margin: 1.5rem 0 0;
  color: rgba(255, 255, 255, 0.86);
  font-size: clamp(1.05rem, 2vw, 1.35rem);
}

.hero-actions,
.hero-stats {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.9rem;
  margin-top: 2rem;
}

.button {
  display: inline-flex;
  min-height: 44px;
  align-items: center;
  justify-content: center;
  padding: 0.72rem 1.05rem;
  border-radius: 8px;
  font-weight: 800;
  text-decoration: none;
}

.button.primary {
  color: #ffffff;
  background: var(--red);
}

.button.secondary {
  color: #ffffff;
  border: 1px solid rgba(255, 255, 255, 0.42);
  background: rgba(255, 255, 255, 0.1);
}

.button.ghost {
  color: var(--red-dark);
  border: 1px solid var(--line);
  background: var(--surface);
}

.button:hover,
.button:focus-visible {
  transform: translateY(-1px);
}

.hero-stats {
  gap: 1.25rem;
  color: rgba(255, 255, 255, 0.78);
}

.hero-stats span {
  display: inline-flex;
  align-items: baseline;
  gap: 0.35rem;
}

.hero-stats strong {
  color: #ffffff;
  font-size: 1.8rem;
}

.section {
  padding: 5.5rem 0;
}

.section:nth-of-type(even) {
  background: var(--surface);
}

.section-inner {
  width: min(1120px, 90vw);
  margin: 0 auto;
}

.section-heading {
  max-width: 720px;
  margin-bottom: 2rem;
}

.section-heading.split {
  display: flex;
  max-width: none;
  align-items: end;
  justify-content: space-between;
  gap: 1.5rem;
}

.section-heading h2 {
  margin: 0;
  font-size: clamp(2rem, 5vw, 4rem);
  line-height: 1;
  letter-spacing: 0;
}

.section-heading p:not(.eyebrow) {
  margin: 1rem 0 0;
  color: var(--muted);
  font-size: 1.06rem;
}

.topic-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1rem;
}

.topic-card,
.lecture-card {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  box-shadow: 0 10px 25px rgba(27, 35, 51, 0.06);
}

.topic-card {
  overflow: hidden;
}

.topic-card img,
.terminal-visual {
  width: 100%;
  aspect-ratio: 1.45;
  object-fit: cover;
  background: #111827;
}

.diagram-boost {
  filter: brightness(1.8) contrast(1.12);
}

.topic-card div:last-child {
  padding: 1rem;
}

.topic-kicker {
  margin: 0 0 0.25rem;
  color: var(--teal);
  font-size: 0.76rem;
  font-weight: 900;
  text-transform: uppercase;
}

.topic-card h3,
.resource-columns h3 {
  margin: 0 0 0.45rem;
  font-size: 1.15rem;
}

.topic-card p:last-child {
  margin: 0;
  color: var(--muted);
  font-size: 0.94rem;
}

.terminal-visual {
  display: grid;
  align-content: center;
  gap: 0.55rem;
  padding: 1.2rem;
  color: #d8f3dc;
  background: #111827;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.92rem;
}

.search-label {
  display: grid;
  gap: 0.4rem;
  min-width: min(100%, 310px);
  color: var(--muted);
  font-size: 0.8rem;
  font-weight: 800;
  text-transform: uppercase;
}

.search-label input {
  width: 100%;
  min-height: 46px;
  padding: 0.75rem 0.9rem;
  color: var(--ink);
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  font: inherit;
  text-transform: none;
}

.lecture-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0.9rem;
}

.lecture-card {
  display: grid;
  min-height: 190px;
  align-content: start;
  gap: 0.65rem;
  padding: 1rem;
  text-decoration: none;
  transition: border-color 160ms ease, box-shadow 160ms ease, transform 160ms ease;
}

.lecture-card:hover,
.lecture-card:focus-visible {
  border-color: rgba(177, 4, 14, 0.48);
  box-shadow: 0 18px 34px rgba(27, 35, 51, 0.13);
  transform: translateY(-2px);
}

.lecture-number {
  display: inline-grid;
  width: fit-content;
  min-width: 48px;
  min-height: 32px;
  place-items: center;
  padding: 0 0.55rem;
  color: #ffffff;
  background: var(--ink);
  border-radius: 6px;
  font-size: 0.78rem;
  font-weight: 900;
}

.lecture-card strong {
  font-size: 1.03rem;
  line-height: 1.25;
}

.lecture-card span:last-child {
  color: var(--muted);
  font-size: 0.92rem;
}

.empty-state {
  padding: 2rem;
  color: var(--muted);
  text-align: center;
  border: 1px dashed var(--line);
  border-radius: 8px;
  background: var(--surface);
}

.toolchain {
  color: #ffffff;
  background: #14213d;
}

.toolchain .section-heading p:not(.eyebrow) {
  color: rgba(255, 255, 255, 0.78);
}

.command-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
}

.command-panel {
  margin: 0;
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.07);
}

.command-panel figcaption {
  padding: 0.85rem 1rem;
  color: rgba(255, 255, 255, 0.78);
  border-bottom: 1px solid rgba(255, 255, 255, 0.16);
  font-size: 0.82rem;
  font-weight: 900;
  text-transform: uppercase;
}

.command-panel pre {
  min-height: 118px;
  margin: 0;
  overflow-x: auto;
  padding: 1rem;
  color: #e0fbfc;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.9rem;
}

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

.resource-list {
  display: grid;
  gap: 0.65rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.resource-list a,
.text-link,
.site-footer a {
  color: var(--red-dark);
  font-weight: 800;
  text-decoration-color: rgba(130, 0, 0, 0.24);
  text-decoration-thickness: 2px;
  text-underline-offset: 4px;
}

.resource-list li {
  padding-bottom: 0.65rem;
  border-bottom: 1px solid var(--line);
}

.site-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 2rem 5vw;
  color: var(--muted);
  background: var(--surface);
  border-top: 1px solid var(--line);
}

.site-footer p {
  margin: 0;
}

.source-page {
  background: #f7f4ee;
}

.source-main {
  width: min(1180px, 92vw);
  margin: 0 auto;
  padding: 4rem 0 5rem;
}

.source-hero {
  margin-bottom: 1.5rem;
}

.source-hero h1 {
  margin: 0;
  font-size: clamp(2rem, 5vw, 4.8rem);
  line-height: 1;
  letter-spacing: 0;
}

.source-path {
  margin: 0.8rem 0 0;
  color: var(--muted);
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  overflow-wrap: anywhere;
}

.source-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
  margin-top: 1.4rem;
}

.source-shell {
  overflow: auto;
  border: 1px solid #222836;
  border-radius: 8px;
  background: #101522;
  box-shadow: var(--shadow);
}

.code-lines {
  margin: 0;
  padding: 1.1rem 0;
  color: #e8eef8;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.92rem;
  line-height: 1.65;
  counter-reset: line;
  list-style: none;
}

.code-lines li {
  display: grid;
  grid-template-columns: 4rem minmax(0, 1fr);
  min-width: max-content;
  padding: 0 1.2rem 0 0;
  counter-increment: line;
}

.code-lines li::before {
  padding-right: 1rem;
  color: #6b7280;
  content: counter(line);
  text-align: right;
  user-select: none;
}

.code-lines code {
  white-space: pre;
}

.source-message {
  margin: 0;
  padding: 1.2rem;
  color: #e8eef8;
}

.handouts-page {
  background: #f6f8fb;
}

.handout-main {
  width: min(1120px, 90vw);
  margin: 0 auto;
  padding: 4.5rem 0 5.5rem;
}

.handout-hero {
  max-width: 780px;
  margin-bottom: 2rem;
}

.handout-hero h1 {
  margin: 0;
  font-size: clamp(2.4rem, 6vw, 5.4rem);
  line-height: 0.98;
  letter-spacing: 0;
}

.handout-copy {
  margin: 1rem 0 0;
  color: var(--muted);
  font-size: 1.08rem;
}

.handout-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
  margin-top: 1.4rem;
}

.handout-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0.9rem;
}

.handout-card {
  display: grid;
  min-height: 154px;
  align-content: start;
  gap: 0.55rem;
  padding: 1rem;
  color: var(--ink);
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  box-shadow: 0 10px 25px rgba(27, 35, 51, 0.06);
  text-decoration: none;
  transition: border-color 160ms ease, box-shadow 160ms ease, transform 160ms ease;
}

.handout-card:hover,
.handout-card:focus-visible {
  border-color: rgba(0, 124, 137, 0.5);
  box-shadow: 0 18px 34px rgba(27, 35, 51, 0.13);
  transform: translateY(-2px);
}

.handout-number {
  display: inline-grid;
  width: fit-content;
  min-width: 42px;
  min-height: 30px;
  place-items: center;
  padding: 0 0.55rem;
  color: #ffffff;
  background: var(--teal);
  border-radius: 6px;
  font-size: 0.74rem;
  font-weight: 900;
  text-transform: uppercase;
}

.handout-card strong {
  font-size: 1.05rem;
  line-height: 1.25;
}

.handout-card span:last-child {
  color: var(--muted);
  font-size: 0.92rem;
}

@media (max-width: 980px) {
  .topic-grid,
  .lecture-grid,
  .handout-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .command-grid,
  .resource-columns {
    grid-template-columns: 1fr;
  }

  .hero-backdrop {
    width: min(58vw, 420px);
    height: min(40vw, 300px);
    opacity: 0.72;
  }
}

@media (max-width: 700px) {
  .site-header {
    align-items: flex-start;
    flex-direction: column;
    gap: 0.85rem;
    padding-top: 0.9rem;
    padding-bottom: 0.9rem;
  }

  .site-nav {
    width: 100%;
    overflow-x: auto;
    padding-bottom: 0.15rem;
  }

  .hero {
    min-height: 72svh;
  }

  .hero-inner {
    padding: 5rem 0 4rem;
  }

  .hero-backdrop {
    display: none;
  }

  .section {
    padding: 3.6rem 0;
  }

  .section-heading.split {
    align-items: stretch;
    flex-direction: column;
  }

  .topic-grid,
  .lecture-grid,
  .handout-grid {
    grid-template-columns: 1fr;
  }

  .lecture-card {
    min-height: 154px;
  }

  .site-footer {
    align-items: flex-start;
    flex-direction: column;
  }
}