:root {
  --brand: #0b84c9;
  --bg: #134b74;
  --ink: #1f2937;
  --muted: #6b7280;
  --link: #1e6bb8;
  --card-shadow: 0 10px 20px rgba(0, 0, 0, 0.12);
  --radius: 6px;
  --maxw: 1180px;
}

* {
  box-sizing: border-box;
}

html,
body {
  height: 100%;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", Arial, sans-serif;
  color: var(--ink);
  background: var(--bg);
}

a {
  color: inherit;
  text-decoration: none;
}

a:focus-visible {
  outline: 2px solid rgba(255, 255, 255, 0.9);
  outline-offset: 2px;
}

/* Top bar */
.topbar {
  background: var(--brand);
  color: #fff;
}

.topbar .inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 16px 20px;
  display: flex;
  align-items: center;
  gap: 12px;
}

.brand-mark {
  width: 32px;
  height: 32px;
  flex: 0 0 auto;
}

.brand-title {
  font-size: 22px;
  font-weight: 700;
  letter-spacing: 0.2px;
}

/* Layout */
.page {
  min-height: calc(100vh - 64px);
}

.container {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 28px 20px 64px;
}

/* Menu box */
.menu {
  background: #fff;
  border-radius: var(--radius);
  box-shadow: var(--card-shadow);
  padding: 18px 100px 18px 20px;
  position: relative;
}

.menu-row {
  display: grid;
  grid-template-columns: auto repeat(8, minmax(0, 1fr));
  align-items: center;
  column-gap: 24px;
  row-gap: 16px;
}

.menu-label {
  color: var(--link);
  font-weight: 800;
  grid-column: 1;
  align-self: center;
}

.menu-label.menu-ghost,
.menu-ghost {
  visibility: hidden;
}

.menu a {
  color: var(--link);
  font-weight: 700;
  padding: 6px 10px;
  border-radius: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  text-align: center;
  white-space: nowrap;
}

.menu a:hover {
  background: rgba(30, 107, 184, 0.08);
}

.menu a.active {
  background: var(--link);
  color: #fff;
}

.menu a[href*="graduation-thesis"] {
  padding-left: 70px;
  padding-right: 60px;
  transform: translateX(-15px);
}

.menu-col-1 {
  grid-column: 2;
}

.menu-col-2 {
  grid-column: 3;
}

.menu-col-3 {
  grid-column: 4;
}

.menu-col-4 {
  grid-column: 5;
}

.menu-col-5 {
  grid-column: 6;
}

.menu-col-6 {
  grid-column: 7;
}

.menu-col-7 {
  grid-column: 8;
}

.menu-col-8 {
  grid-column: 9;
}

.menu-toggle summary {
  position: absolute;
  top: 18px;
  right: 20px;
  list-style: none;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 0;
  cursor: pointer;
  font-weight: 800;
  color: var(--ink);
}

.menu-toggle summary::-webkit-details-marker {
  display: none;
}

.menu-caret {
  display: inline-block;
  width: 0;
  height: 0;
  border-left: 6px solid transparent;
  border-right: 6px solid transparent;
  border-top: 7px solid var(--ink);
  transform: translateY(1px);
}

.menu-toggle[open] .menu-caret {
  border-top: 0;
  border-bottom: 7px solid var(--ink);
  transform: translateY(-1px);
}

.menu-toggle .menu-row.bottom {
  margin-top: 12px;
}

.menu-toggle:not([open]) .menu-row.bottom {
  display: none;
}

/* Cards */
.cards {
  margin-top: 44px;
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 24px;
}

.card {
  width: 100%;
  aspect-ratio: 1 / 1;
  height: auto;
  background: #fff;
  border-radius: var(--radius);
  box-shadow: var(--card-shadow);
  padding: 20px 16px;
  position: relative;
  min-height: 0;
  overflow: hidden;
  transition: transform 0.12s ease, box-shadow 0.12s ease;
}

.card:hover {
  transform: translateY(-2px);
  box-shadow: 0 14px 26px rgba(0, 0, 0, 0.16);
}

.card-icon {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  margin: 15px auto 0;
  display: flex;
  align-items: center;
  justify-content: center;
}

.card-icon svg {
  width: 48px;
  height: 48px;
}

.card-title {
  margin-top: 20px;
  text-align: center;
  font-size: 16px;
  font-weight: 800;
  color: #404040;
  line-height: 1.2;
  max-width: 100%;
  white-space: nowrap;
  overflow: hidden;
}

.card-meta {
  margin-top: 10px;
  text-align: center;
  color: var(--muted);
  font-size: 13px;
}

.card-detail {
  position: absolute;
  right: 16px;
  bottom: 14px;
  font-weight: 700;
  color: var(--link);
  font-size: 13px;
}

.card-detail span {
  display: inline-block;
  transform: translateY(-1px);
  margin-left: 6px;
}

/* Placeholder */
.placeholder {
  margin-top: 44px;
  background: #fff;
  border-radius: var(--radius);
  box-shadow: var(--card-shadow);
  padding: 26px;
}

.placeholder h1 {
  margin: 0;
  font-size: 20px;
}

.placeholder p {
  margin: 10px 0 0;
  color: var(--muted);
  line-height: 1.6;
}

.placeholder a:link {
  color: #0000EE;
  /* Standard blue */
  text-decoration: underline;
  cursor: pointer;
}

.placeholder a:visited {
  color: #551A8B;
  /* Standard purple */
  text-decoration: underline;
}

.placeholder a:active {
  color: #FF0000;
  /* Bright red */
}

.placeholder a:focus {
  outline: thin dotted;
  /* Classic focus ring */
}


@media (max-width: 1200px) {
  .cards {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (max-width: 980px) {
  .cards {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .menu {
    padding-right: 20px;
  }

  .menu-row {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: 16px;
  }

  .menu-label,
  .menu-label.menu-ghost {
    grid-column: 1 / -1;
    visibility: visible;
  }

  .menu a {
    width: auto;
    justify-content: flex-start;
    text-align: left;
    white-space: normal;
  }

  .menu-toggle {
    position: static;
    display: block;
    text-align: right;
    margin-top: 10px;
  }

  .menu-toggle summary {
    position: static;
  }

  .menu-toggle .menu-row.bottom {
    margin-top: 8px;
  }

  .menu-col-1,
  .menu-col-2,
  .menu-col-3,
  .menu-col-4,
  .menu-col-5,
  .menu-col-6,
  .menu-col-7,
  .menu-col-8 {
    grid-column: auto;
  }
}

@media (max-width: 720px) {
  .cards {
    gap: 18px;
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .card {
    width: 100%;
  }
}

@media (max-width: 520px) {
  .cards {
    grid-template-columns: 1fr;
  }
}