:root {
  color-scheme: light;
  --bg: #f6f7f9;
  --surface: #ffffff;
  --surface-alt: #eef4f2;
  --ink: #172026;
  --muted: #63717c;
  --line: #d8dee4;
  --accent: #1f6f78;
  --accent-strong: #174d55;
  --accent-soft: #dcefed;
  --warning: #9b5d12;
  --aws: #7a4f03;
  --kubernetes: #326ce5;
  --linux: #3b5666;
  --networking: #087f5b;
  --radius: 8px;
  --shadow: 0 18px 60px rgba(18, 32, 42, 0.08);
}

* {
  box-sizing: border-box;
}

html {
  min-width: 320px;
}

body {
  margin: 0;
  background:
    linear-gradient(180deg, rgba(31, 111, 120, 0.08), rgba(246, 247, 249, 0) 280px),
    var(--bg);
  color: var(--ink);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.5;
}

button,
input,
select {
  font: inherit;
}

.app-header {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 24px;
  max-width: 1220px;
  margin: 0 auto;
  padding: 40px 24px 22px;
}

.eyebrow {
  margin: 0 0 7px;
  color: var(--accent);
  font-size: 0.77rem;
  font-weight: 700;
  letter-spacing: 0;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  overflow-wrap: anywhere;
}

h1 {
  margin: 0;
  max-width: 780px;
  line-height: 0.98;
  letter-spacing: 0;
}

.header-stats {
  display: grid;
  min-width: 104px;
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.72);
  text-align: right;
}

.header-stats span:first-child {
  font-size: 1.55rem;
  font-weight: 750;
  line-height: 1;
}

.header-stats span:last-child {
  color: var(--muted);
  font-size: 0.82rem;
}

.app-shell {
  display: grid;
  grid-template-columns: minmax(240px, 300px) minmax(0, 1fr);
  gap: 20px;
  max-width: 1220px;
  margin: 0 auto;
  padding: 0 24px 48px;
}

.filters,
.questions-panel {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.92);
  box-shadow: var(--shadow);
}

.filters {
  align-self: start;
  position: sticky;
  top: 16px;
  max-height: calc(100vh - 32px);
  overflow-y: auto;
  display: grid;
  gap: 18px;
  padding: 18px;
  scrollbar-gutter: stable;
}

.filters::-webkit-scrollbar {
  width: 10px;
}

.filters::-webkit-scrollbar-track {
  background: transparent;
}

.filters::-webkit-scrollbar-thumb {
  border: 2px solid rgba(255, 255, 255, 0.92);
  border-radius: 999px;
  background: #b9c5cc;
}

.filter-group {
  display: grid;
  gap: 8px;
}

label,
.filter-label {
  color: var(--muted);
  font-size: 0.83rem;
  font-weight: 700;
}

input,
select {
  width: 100%;
  min-height: 42px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--surface);
  color: var(--ink);
}

input {
  padding: 0 12px;
}

select {
  padding: 0 10px;
}

input:focus,
select:focus,
button:focus-visible {
  outline: 3px solid rgba(31, 111, 120, 0.22);
  outline-offset: 2px;
}

.chip-list,
.active-filters,
.question-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.chip {
  min-height: 32px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--surface);
  color: var(--ink);
  cursor: pointer;
  font-size: 0.86rem;
  font-weight: 650;
  padding: 5px 10px;
}

.chip[aria-pressed="true"] {
  border-color: var(--accent);
  background: var(--accent-soft);
  color: var(--accent-strong);
}

.secondary-button {
  min-height: 40px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #f8fafb;
  color: var(--ink);
  cursor: pointer;
  font-weight: 700;
}

.secondary-button:hover,
.chip:hover,
.answer-toggle:hover {
  border-color: var(--accent);
}

.questions-panel {
  min-width: 0;
  overflow: hidden;
}

.panel-heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 72px;
  padding: 18px 20px;
  border-bottom: 1px solid var(--line);
  background: var(--surface-alt);
}

h2 {
  margin: 0;
  font-size: 1.18rem;
}

.active-filters {
  justify-content: flex-end;
}

.active-filter {
  border-radius: 999px;
  background: rgba(31, 111, 120, 0.1);
  color: var(--accent-strong);
  font-size: 0.8rem;
  font-weight: 700;
  padding: 4px 9px;
}

.question-list {
  display: grid;
}

.question-card {
  display: grid;
  gap: 14px;
  padding: 20px;
  border-bottom: 1px solid var(--line);
  background: var(--surface);
}

.question-card:last-child {
  border-bottom: 0;
}

.question-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.role-label {
  color: var(--muted);
  font-size: 0.82rem;
  font-weight: 750;
}

.difficulty {
  border: 1px solid rgba(155, 93, 18, 0.24);
  border-radius: 999px;
  background: rgba(155, 93, 18, 0.08);
  color: var(--warning);
  font-size: 0.78rem;
  font-weight: 750;
  padding: 3px 8px;
}

h3 {
  margin: 0;
  font-size: 1.08rem;
  line-height: 1.35;
}

.question-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
}

.tag {
  border-radius: 999px;
  background: #edf0f2;
  color: #34444f;
  font-size: 0.77rem;
  font-weight: 750;
  padding: 4px 8px;
}

.tag[data-category="AWS"] {
  background: rgba(122, 79, 3, 0.1);
  color: var(--aws);
}

.tag[data-category="Kubernetes"] {
  background: rgba(50, 108, 229, 0.1);
  color: var(--kubernetes);
}

.tag[data-category="Linux"] {
  background: rgba(59, 86, 102, 0.13);
  color: var(--linux);
}

.tag[data-category="Networking"] {
  background: rgba(8, 127, 91, 0.1);
  color: var(--networking);
}

.answer-toggle {
  flex: 0 0 auto;
  min-height: 36px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--surface);
  color: var(--accent-strong);
  cursor: pointer;
  font-weight: 750;
  padding: 0 12px;
}

.answer {
  display: grid;
  gap: 10px;
  max-width: 76ch;
  border-left: 3px solid var(--accent);
  background: #f8fbfb;
  padding: 14px 16px;
}

.answer[hidden] {
  display: none;
}

.answer p {
  margin: 0;
}

.answer ul {
  margin: 0;
  padding-left: 20px;
}

.answer li + li {
  margin-top: 5px;
}

.empty-state {
  margin: 0;
  padding: 28px 20px;
  color: var(--muted);
}

@media (max-width: 820px) {
  .app-header {
    align-items: stretch;
    flex-direction: column;
    padding: 30px 16px 18px;
  }

  .header-stats {
    justify-items: start;
    text-align: left;
  }

  .app-shell {
    grid-template-columns: 1fr;
    padding: 0 16px 36px;
  }

  .filters {
    position: static;
    max-height: none;
    overflow: visible;
  }

  .panel-heading,
  .question-meta,
  .question-footer {
    align-items: flex-start;
    flex-direction: column;
  }

  .active-filters {
    justify-content: flex-start;
  }

  .answer-toggle {
    width: 100%;
  }
}