:root {
  --qtf-bg: #f4f3ef;
  --qtf-surface: #ffffff;
  --qtf-ink: #121417;
  --qtf-muted: #4b5563;
  --qtf-soft: #9ca3af;
  --qtf-line: #e5e2dc;
  --qtf-head: #0d1117;
  --qtf-brand: #2aabee;
  --qtf-brand-d: #229ed9;
  --qtf-glow: rgba(42, 171, 238, 0.35);
  --qtf-max: 1120px;
  --qtf-radius: 14px;
  --qtf-radius-sm: 10px;
  --qtf-font: ui-sans-serif, system-ui, -apple-system, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--qtf-font);
  font-size: 16px;
  line-height: 1.65;
  color: var(--qtf-ink);
  background: var(--qtf-bg);
  -webkit-font-smoothing: antialiased;
}

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

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

a:hover {
  color: var(--qtf-brand-d);
}

.qtf-shell {
  max-width: var(--qtf-max);
  margin: 0 auto;
  padding: 0 22px;
}

.qtf-skip {
  position: absolute;
  left: -9999px;
  top: 0;
  z-index: 100;
  padding: 10px 14px;
  background: var(--qtf-head);
  color: #fff;
  border-radius: var(--qtf-radius-sm);
}

.qtf-skip:focus {
  left: 12px;
  top: 12px;
}

/* —— Header —— */
.qtf-head {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--qtf-head);
  color: #e6edf3;
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.qtf-head__row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 68px;
}

.qtf-logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: #fff;
}

.qtf-logo:hover {
  color: #fff;
  opacity: 0.92;
}

.qtf-logo__img {
  height: 28px;
  width: auto;
}

.qtf-logo__txt {
  font-weight: 700;
  font-size: 15px;
  letter-spacing: 0.04em;
}

.qtf-nav {
  display: flex;
  align-items: center;
  gap: 8px;
}

.qtf-nav__link {
  padding: 8px 14px;
  border-radius: 999px;
  font-size: 14px;
  font-weight: 600;
  color: #c9d1d9;
}

.qtf-nav__link:hover {
  color: #fff;
  background: rgba(255, 255, 255, 0.06);
}

.qtf-head__tools {
  display: flex;
  align-items: center;
  gap: 10px;
}

.qtf-burger {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  padding: 0;
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: var(--qtf-radius-sm);
  background: rgba(255, 255, 255, 0.04);
  cursor: pointer;
}

.qtf-burger__bar {
  display: block;
  width: 18px;
  height: 2px;
  margin: 0 auto;
  background: #fff;
  border-radius: 1px;
}

/* —— Buttons —— */
.qtf-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  font-size: 14px;
  font-weight: 700;
  border-radius: var(--qtf-radius-sm);
  border: 1px solid transparent;
  cursor: pointer;
  transition: background 0.15s ease, border-color 0.15s ease, color 0.15s ease, box-shadow 0.15s ease;
  white-space: nowrap;
}

.qtf-btn--sm {
  padding: 9px 16px;
  font-size: 13px;
}

.qtf-btn--solid {
  background: linear-gradient(135deg, var(--qtf-brand) 0%, var(--qtf-brand-d) 100%);
  color: #fff;
  box-shadow: 0 8px 24px var(--qtf-glow);
}

.qtf-btn--solid:hover {
  color: #fff;
  filter: brightness(1.05);
}

.qtf-btn--line {
  border-color: var(--qtf-line);
  background: var(--qtf-surface);
  color: var(--qtf-ink);
}

.qtf-btn--line:hover {
  border-color: var(--qtf-brand-d);
  color: var(--qtf-brand-d);
}

.qtf-btn--ghost {
  border-color: var(--qtf-line);
  background: transparent;
  color: var(--qtf-ink);
}

.qtf-btn--ghost:hover {
  border-color: var(--qtf-brand-d);
  color: var(--qtf-brand-d);
}

.qtf-btn--block {
  width: 100%;
}

.qtf-btn--disabled {
  opacity: 0.45;
  pointer-events: none;
}

/* —— Main / Hero —— */
.qtf-main {
  display: block;
}

.qtf-hero {
  position: relative;
  padding: 72px 0 56px;
  overflow: hidden;
}

.qtf-hero__bg {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 900px 420px at 70% -10%, rgba(42, 171, 238, 0.2), transparent 55%),
    linear-gradient(180deg, #ebe8e0 0%, var(--qtf-bg) 100%);
  pointer-events: none;
}

.qtf-hero__bg::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image: linear-gradient(rgba(18, 20, 23, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(18, 20, 23, 0.04) 1px, transparent 1px);
  background-size: 28px 28px;
  opacity: 0.5;
  mask-image: linear-gradient(180deg, #000 30%, transparent 95%);
}

.qtf-hero__inner {
  position: relative;
  max-width: 820px;
}

.qtf-hero__eyebrow {
  margin: 0 0 12px;
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--qtf-brand-d);
}

.qtf-hero__h1 {
  margin: 0;
  font-size: clamp(28px, 5vw, 44px);
  line-height: 1.12;
  font-weight: 800;
  letter-spacing: -0.02em;
}

.qtf-hero__sub {
  margin: 18px 0 0;
  font-size: 17px;
  color: var(--qtf-muted);
  max-width: 52em;
}

.qtf-hero__actions {
  margin-top: 28px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.qtf-hero__tags {
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.qtf-pill {
  padding: 6px 12px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 700;
  background: var(--qtf-surface);
  border: 1px solid var(--qtf-line);
  color: var(--qtf-muted);
}

/* —— Band / Trio —— */
.qtf-band {
  padding: 56px 0 64px;
  background: var(--qtf-surface);
  border-top: 1px solid var(--qtf-line);
  border-bottom: 1px solid var(--qtf-line);
}

.qtf-h2 {
  margin: 0;
  font-size: clamp(22px, 3vw, 30px);
  font-weight: 800;
  letter-spacing: -0.02em;
}

.qtf-h2--center {
  text-align: center;
}

.qtf-lead {
  margin: 14px 0 0;
  font-size: 16px;
  color: var(--qtf-muted);
}

.qtf-lead--center {
  text-align: center;
  max-width: 640px;
  margin-left: auto;
  margin-right: auto;
}

.qtf-trio {
  margin-top: 36px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.qtf-trio__card {
  padding: 22px 20px;
  border-radius: var(--qtf-radius);
  border: 1px solid var(--qtf-line);
  background: var(--qtf-bg);
  border-left: 4px solid var(--qtf-brand-d);
}

.qtf-trio__t {
  margin: 0;
  font-size: 17px;
  font-weight: 800;
}

.qtf-trio__d {
  margin: 10px 0 0;
  font-size: 14px;
  color: var(--qtf-muted);
  line-height: 1.6;
}

/* —— Shots —— */
.qtf-shots {
  padding: 48px 0;
}

.qtf-shots__grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
}

.qtf-shot {
  margin: 0;
  border-radius: var(--qtf-radius);
  overflow: hidden;
  border: 1px solid var(--qtf-line);
  background: var(--qtf-surface);
  box-shadow: 0 20px 50px rgba(18, 20, 23, 0.08);
}

.qtf-shot__img {
  width: 100%;
}

.qtf-shot__cap {
  padding: 12px 16px 16px;
  font-size: 13px;
  color: var(--qtf-muted);
}

/* —— Mosaic —— */
.qtf-gridsec {
  padding: 56px 0 72px;
}

.qtf-mosaic {
  margin-top: 32px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
}

.qtf-tile {
  padding: 18px 16px;
  border-radius: var(--qtf-radius-sm);
  border: 1px solid var(--qtf-line);
  background: var(--qtf-surface);
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

.qtf-tile:hover {
  border-color: rgba(34, 158, 217, 0.45);
  box-shadow: 0 10px 30px rgba(18, 20, 23, 0.06);
}

.qtf-tile__gif {
  width: 52px;
  height: 52px;
  object-fit: contain;
}

.qtf-tile__t {
  margin: 10px 0 0;
  font-size: 15px;
  font-weight: 800;
}

.qtf-tile__d {
  margin: 6px 0 0;
  font-size: 13px;
  color: var(--qtf-muted);
  line-height: 1.55;
}

/* —— Blog cards —— */
.qtf-blog {
  padding: 48px 0 80px;
  background: var(--qtf-surface);
  border-top: 1px solid var(--qtf-line);
}

.qtf-blog__head,
.qtf-related__head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 22px;
}

.qtf-blog__more {
  font-size: 14px;
  font-weight: 800;
  color: var(--qtf-brand-d);
}

.qtf-blog__more:hover {
  color: var(--qtf-brand);
}

.qtf-blog__grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.qtf-card {
  border-radius: var(--qtf-radius);
  border: 1px solid var(--qtf-line);
  background: var(--qtf-bg);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.qtf-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 16px 40px rgba(18, 20, 23, 0.08);
}

.qtf-card__media {
  display: block;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background: #e8e6e1;
}

.qtf-card__media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.qtf-card__body {
  padding: 14px 16px 18px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  flex: 1;
}

.qtf-card__title {
  margin: 0;
  font-size: 16px;
  font-weight: 800;
  line-height: 1.35;
}

.qtf-card__title a:hover {
  color: var(--qtf-brand-d);
}

.qtf-card__time {
  font-size: 12px;
  color: var(--qtf-soft);
}

.qtf-card__excerpt {
  margin: 0;
  font-size: 13px;
  color: var(--qtf-muted);
  line-height: 1.55;
  flex: 1;
}

.qtf-card--row {
  flex-direction: row;
  align-items: stretch;
}

.qtf-card__media--sm {
  width: 200px;
  min-width: 200px;
  aspect-ratio: auto;
  height: auto;
  align-self: stretch;
}

.qtf-card__media--sm img {
  height: 100%;
  min-height: 140px;
}

.qtf-card--mini .qtf-card__excerpt {
  display: none;
}

.qtf-card--mini .qtf-card__body {
  padding: 12px 14px 14px;
}

/* —— Page head —— */
.qtf-pagehead {
  padding: 48px 0 36px;
  background: linear-gradient(180deg, #e8e4db 0%, var(--qtf-bg) 100%);
  border-bottom: 1px solid var(--qtf-line);
}

.qtf-pagehead--compact {
  padding: 40px 0 28px;
}

.qtf-pagehead__inner {
  max-width: 720px;
}

.qtf-pagehead__h1 {
  margin: 0;
  font-size: clamp(26px, 4vw, 38px);
  font-weight: 800;
  letter-spacing: -0.02em;
}

.qtf-pagehead__sub,
.qtf-pagehead__meta {
  margin: 14px 0 0;
  color: var(--qtf-muted);
  font-size: 15px;
}

.qtf-pagehead__row {
  margin-top: 20px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.qtf-pagehead__anchors {
  margin: 16px 0 0;
  font-size: 14px;
  font-weight: 700;
  color: var(--qtf-brand-d);
}

.qtf-pagehead__anchors a:hover {
  text-decoration: underline;
}

.qtf-dot {
  margin: 0 6px;
  color: var(--qtf-soft);
}

/* —— Platforms —— */
.qtf-platforms {
  padding: 40px 0 24px;
}

.qtf-platforms__grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.qtf-plat {
  border-radius: var(--qtf-radius);
  border: 1px solid var(--qtf-line);
  background: var(--qtf-surface);
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

.qtf-plat__shot img {
  width: 100%;
}

.qtf-plat__body {
  padding: 16px 18px 18px;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.qtf-plat__t {
  margin: 0;
  font-size: 18px;
  font-weight: 800;
}

.qtf-plat__d {
  margin: 8px 0 0;
  font-size: 14px;
  color: var(--qtf-muted);
  flex: 1;
}

.qtf-plat__act {
  margin-top: 14px;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

/* —— Prose / Paper —— */
.qtf-article {
  padding: 32px 0 56px;
}

.qtf-paper {
  max-width: 760px;
  margin: 0 auto;
  padding: 28px 26px 32px;
  border-radius: var(--qtf-radius);
  border: 1px solid var(--qtf-line);
  background: var(--qtf-surface);
}

.qtf-paper--post {
  max-width: none;
}

.qtf-prose {
  font-size: 16px;
  color: var(--qtf-ink);
}

.qtf-prose h2,
.qtf-prose h3 {
  margin: 22px 0 10px;
  font-weight: 800;
  letter-spacing: -0.02em;
}

.qtf-prose p {
  margin: 10px 0;
}

.qtf-prose a {
  color: var(--qtf-brand-d);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.qtf-prose ul,
.qtf-prose ol {
  margin: 10px 0;
  padding-left: 1.25em;
}

.qtf-faq {
  border: 1px solid var(--qtf-line);
  border-radius: var(--qtf-radius-sm);
  background: var(--qtf-bg);
  margin-bottom: 10px;
}

.qtf-faq__q {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 14px 16px;
  border: none;
  background: transparent;
  font-size: 15px;
  font-weight: 800;
  text-align: left;
  cursor: pointer;
  color: var(--qtf-ink);
}

.qtf-faq__ic {
  font-size: 18px;
  color: var(--qtf-soft);
}

.qtf-faq__a {
  padding: 0 16px 14px;
  font-size: 14px;
  color: var(--qtf-muted);
  line-height: 1.6;
}

/* —— Tiles (article index) —— */
.qtf-tiles {
  padding: 36px 0 72px;
}

.qtf-tiles__grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.qtf-tilelink {
  display: block;
  padding: 22px 20px;
  border-radius: var(--qtf-radius);
  border: 1px solid var(--qtf-line);
  background: var(--qtf-surface);
  transition: border-color 0.15s ease, background 0.15s ease;
}

.qtf-tilelink:hover {
  border-color: var(--qtf-brand-d);
  background: #faf9f7;
}

.qtf-tilelink__t {
  display: block;
  font-size: 17px;
  font-weight: 800;
}

.qtf-tilelink__d {
  display: block;
  margin-top: 8px;
  font-size: 14px;
  color: var(--qtf-muted);
  line-height: 1.5;
}

/* —— List / Pager —— */
.qtf-list {
  padding: 8px 0 72px;
}

.qtf-list__grid {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.qtf-pager {
  margin-top: 28px;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 8px;
}

.qtf-pager a,
.qtf-pager span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 40px;
  height: 40px;
  padding: 0 12px;
  border-radius: var(--qtf-radius-sm);
  border: 1px solid var(--qtf-line);
  background: var(--qtf-surface);
  font-size: 14px;
  font-weight: 600;
  color: var(--qtf-muted);
}

.qtf-pager a:hover {
  border-color: var(--qtf-brand-d);
  color: var(--qtf-brand-d);
}

.qtf-pager .current,
.qtf-pager .active {
  border-color: var(--qtf-brand-d);
  background: rgba(34, 158, 217, 0.12);
  color: var(--qtf-brand-d);
}

/* —— Related / canonical —— */
.qtf-related {
  padding: 0 0 80px;
}

.qtf-related__pn {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
  margin-bottom: 40px;
}

.qtf-canonical {
  margin-top: 28px;
  font-size: 13px;
  color: var(--qtf-soft);
  word-break: break-all;
}

.qtf-canonical a {
  color: var(--qtf-brand-d);
  text-decoration: underline;
}

/* —— Footer —— */
.qtf-foot {
  background: var(--qtf-head);
  color: #8b949e;
  padding: 44px 0 28px;
  font-size: 14px;
}

.qtf-foot__grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr auto;
  gap: 28px;
  align-items: start;
}

.qtf-foot__lead {
  margin: 0;
  line-height: 1.65;
  max-width: 36em;
}

.qtf-foot__label {
  display: block;
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: #6e7681;
  margin-bottom: 10px;
}

.qtf-foot__btns {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.qtf-foot .qtf-btn--solid {
  box-shadow: none;
}

.qtf-foot .qtf-btn--ghost {
  border-color: rgba(255, 255, 255, 0.14);
  color: #e6edf3;
}

.qtf-foot .qtf-btn--ghost:hover {
  border-color: var(--qtf-brand);
  color: #fff;
}

.qtf-foot__links {
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-weight: 700;
}

.qtf-foot__links a {
  color: #c9d1d9;
}

.qtf-foot__links a:hover {
  color: #fff;
}

.qtf-foot__copy {
  margin: 32px 0 0;
  padding-top: 22px;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  font-size: 12px;
  color: #6e7681;
  line-height: 1.6;
}

/* —— 404 —— */
.qtf-miss {
  padding: 100px 0 120px;
  text-align: center;
}

.qtf-miss__box {
  max-width: 480px;
  margin: 0 auto;
}

.qtf-miss__code {
  margin: 0;
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0.3em;
  color: var(--qtf-brand-d);
}

.qtf-miss__h1 {
  margin: 12px 0 0;
  font-size: clamp(26px, 4vw, 34px);
  font-weight: 800;
}

.qtf-miss__txt {
  margin: 14px 0 0;
  color: var(--qtf-muted);
}

.qtf-miss__act {
  margin-top: 26px;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
}

@media (max-width: 900px) {
  .qtf-burger {
    display: inline-flex;
  }

  .qtf-nav {
    position: absolute;
    top: 100%;
    left: 16px;
    right: 16px;
    margin-top: 8px;
    flex-direction: column;
    align-items: stretch;
    padding: 10px;
    background: #161b22;
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: var(--qtf-radius-sm);
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.35);
    z-index: 60;
  }

  .qtf-nav[aria-hidden="true"] {
    display: none;
  }

  .qtf-nav__link {
    border-radius: var(--qtf-radius-sm);
  }

  .qtf-head__row {
    flex-wrap: wrap;
  }

  .qtf-trio {
    grid-template-columns: 1fr;
  }

  .qtf-shots__grid {
    grid-template-columns: 1fr;
  }

  .qtf-mosaic {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .qtf-blog__grid {
    grid-template-columns: 1fr;
  }

  .qtf-platforms__grid {
    grid-template-columns: 1fr;
  }

  .qtf-foot__grid {
    grid-template-columns: 1fr;
  }

  .qtf-card--row {
    flex-direction: column;
  }

  .qtf-card__media--sm {
    width: 100%;
    min-width: 0;
    aspect-ratio: 16 / 9;
  }

  .qtf-card__media--sm img {
    min-height: 0;
    height: 100%;
  }

  .qtf-related__pn {
    grid-template-columns: 1fr;
  }

  .qtf-tiles__grid {
    grid-template-columns: 1fr;
  }
}

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