:root {
  --primary: #e85d3d;
  --primary-dark: #c94426;
  --primary-light: #ff8a6b;
  --secondary: #ffb347;
  --accent: #6c5ce7;
  --accent-light: #a29bfe;
  --bg: #fdf8f5;
  --bg-alt: #ffffff;
  --bg-card: rgba(255, 255, 255, 0.72);
  --bg-glass: rgba(255, 255, 255, 0.55);
  --text: #2d2420;
  --text-soft: #5a4d47;
  --text-muted: #8a7d77;
  --border: rgba(232, 93, 61, 0.14);
  --border-strong: rgba(232, 93, 61, 0.28);
  --shadow-sm: 0 2px 8px rgba(45, 36, 32, 0.06);
  --shadow-md: 0 8px 28px rgba(45, 36, 32, 0.1);
  --shadow-lg: 0 18px 50px rgba(45, 36, 32, 0.14);
  --radius-sm: 12px;
  --radius-md: 20px;
  --radius-lg: 28px;
  --radius-pill: 999px;
  --grad-banner: linear-gradient(135deg, #e85d3d 0%, #ff8a6b 38%, #ffb347 68%, #ffd36b 100%);
  --grad-text: linear-gradient(120deg, #e85d3d, #ff8a6b 45%, #ffb347);
  --grad-accent: linear-gradient(135deg, #6c5ce7, #a29bfe);
  --max-width: 1180px;
  --transition: 0.32s cubic-bezier(0.22, 1, 0.36, 1);
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #16110f;
    --bg-alt: #1e1815;
    --bg-card: rgba(38, 30, 27, 0.72);
    --bg-glass: rgba(38, 30, 27, 0.55);
    --text: #f5ece7;
    --text-soft: #d4c6bf;
    --text-muted: #a3948c;
    --border: rgba(255, 138, 107, 0.16);
    --border-strong: rgba(255, 138, 107, 0.32);
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 8px 28px rgba(0, 0, 0, 0.42);
    --shadow-lg: 0 18px 50px rgba(0, 0, 0, 0.55);
    --grad-banner: linear-gradient(135deg, #b8402a 0%, #d95a3e 35%, #e8873f 70%, #c99a3a 100%);
  }
}

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

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

body {
  font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.78;
  font-size: 16px;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -2;
  background:
    radial-gradient(circle at 12% 8%, rgba(232, 93, 61, 0.1), transparent 42%),
    radial-gradient(circle at 88% 22%, rgba(255, 179, 71, 0.12), transparent 46%),
    radial-gradient(circle at 50% 96%, rgba(108, 92, 231, 0.08), transparent 48%);
  pointer-events: none;
}

a {
  color: var(--primary);
  text-decoration: none;
  transition: color var(--transition), opacity var(--transition);
}

a:hover,
a:focus-visible {
  color: var(--primary-dark);
}

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

ul {
  list-style: none;
}

::selection {
  background: rgba(232, 93, 61, 0.24);
  color: var(--text);
}

:focus-visible {
  outline: 2px solid var(--primary);
  outline-offset: 3px;
  border-radius: 4px;
}

/* ============ HEADER ============ */
header {
  position: sticky;
  top: 0;
  z-index: 100;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px 24px;
  padding: 14px clamp(16px, 4vw, 48px);
  background: var(--bg-glass);
  -webkit-backdrop-filter: blur(18px) saturate(180%);
  backdrop-filter: blur(18px) saturate(180%);
  border-bottom: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
}

.brand {
  display: flex;
  flex-direction: column;
  gap: 2px;
  min-width: 0;
}

.brand a {
  font-size: clamp(1.25rem, 2.4vw, 1.5rem);
  font-weight: 800;
  letter-spacing: 0.5px;
  background: var(--grad-text);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  transition: filter var(--transition);
}

.brand a:hover {
  filter: brightness(1.12);
}

.brand span {
  font-size: 0.72rem;
  color: var(--text-muted);
  letter-spacing: 0.3px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: 340px;
}

header nav ul {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 4px;
}

header nav a {
  display: inline-block;
  padding: 7px 13px;
  font-size: 0.86rem;
  font-weight: 500;
  color: var(--text-soft);
  border-radius: var(--radius-pill);
  transition: background var(--transition), color var(--transition), transform var(--transition);
}

header nav a:hover,
header nav a:focus-visible {
  background: rgba(232, 93, 61, 0.12);
  color: var(--primary);
  transform: translateY(-2px);
}

/* ============ MAIN ============ */
main {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: clamp(20px, 4vw, 44px) clamp(16px, 4vw, 32px) 60px;
}

section {
  margin-bottom: clamp(28px, 4vw, 48px);
  padding: clamp(20px, 3.4vw, 40px);
  background: var(--bg-card);
  -webkit-backdrop-filter: blur(14px) saturate(150%);
  backdrop-filter: blur(14px) saturate(150%);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition), transform var(--transition), border-color var(--transition);
  animation: fadeUp 0.7s cubic-bezier(0.22, 1, 0.36, 1) both;
}

section:hover {
  box-shadow: var(--shadow-md);
  border-color: var(--border-strong);
}

@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(26px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

section:nth-of-type(2) { animation-delay: 0.05s; }
section:nth-of-type(3) { animation-delay: 0.1s; }
section:nth-of-type(4) { animation-delay: 0.14s; }
section:nth-of-type(5) { animation-delay: 0.18s; }
section:nth-of-type(6) { animation-delay: 0.22s; }

/* ============ HERO ============ */
#hero {
  position: relative;
  overflow: hidden;
  padding: clamp(30px, 5vw, 64px) clamp(22px, 4vw, 52px);
  background: var(--grad-banner);
  border: none;
  border-radius: var(--radius-lg);
  color: #fff;
  box-shadow: var(--shadow-lg);
  isolation: isolate;
}

#hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background:
    radial-gradient(circle at 82% 12%, rgba(255, 255, 255, 0.32), transparent 40%),
    radial-gradient(circle at 8% 88%, rgba(255, 255, 255, 0.18), transparent 44%);
  pointer-events: none;
}

#hero::after {
  content: "";
  position: absolute;
  width: 380px;
  height: 380px;
  right: -120px;
  bottom: -160px;
  z-index: -1;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.14);
  filter: blur(6px);
  animation: floatBlob 9s ease-in-out infinite alternate;
}

@keyframes floatBlob {
  from { transform: translate(0, 0) scale(1); }
  to { transform: translate(-26px, -22px) scale(1.08); }
}

#hero h1 {
  font-size: clamp(1.5rem, 3.6vw, 2.35rem);
  line-height: 1.35;
  font-weight: 800;
  letter-spacing: 0.4px;
  margin-bottom: 18px;
  text-shadow: 0 2px 18px rgba(120, 40, 20, 0.28);
}

#hero p {
  font-size: clamp(0.92rem, 1.6vw, 1.02rem);
  line-height: 1.9;
  color: rgba(255, 255, 255, 0.94);
  max-width: 900px;
  margin-bottom: 14px;
  text-shadow: 0 1px 8px rgba(120, 40, 20, 0.18);
}

#hero p:last-child {
  margin-bottom: 0;
}

/* ============ TYPOGRAPHY ============ */
h2 {
  position: relative;
  font-size: clamp(1.3rem, 2.6vw, 1.72rem);
  font-weight: 800;
  line-height: 1.4;
  letter-spacing: 0.3px;
  color: var(--text);
  margin-bottom: 18px;
  padding-left: 18px;
}

h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.18em;
  bottom: 0.18em;
  width: 6px;
  border-radius: var(--radius-pill);
  background: var(--grad-text);
}

h3 {
  font-size: clamp(1.02rem, 1.9vw, 1.18rem);
  font-weight: 700;
  color: var(--text);
  margin: 22px 0 10px;
  line-height: 1.5;
  transition: color var(--transition);
}

h3::first-letter {
  color: var(--primary);
}

p {
  color: var(--text-soft);
  font-size: 0.96rem;
  margin-bottom: 12px;
}

p:last-child {
  margin-bottom: 0;
}

strong {
  color: var(--primary-dark);
  font-weight: 700;
}

/* ============ ARTICLES / CARDS ============ */
article {
  position: relative;
  padding: clamp(16px, 2.4vw, 24px);
  margin-bottom: 16px;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
}

article:last-child {
  margin-bottom: 0;
}

article:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--border-strong);
}

article h3 {
  margin-top: 0;
}

article p {
  font-size: 0.92rem;
}

article a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 8px;
  padding: 7px 18px;
  font-size: 0.85rem;
  font-weight: 600;
  color: #fff;
  background: var(--grad-text);
  border-radius: var(--radius-pill);
  box-shadow: 0 4px 14px rgba(232, 93, 61, 0.3);
  transition: transform var(--transition), box-shadow var(--transition), filter var(--transition);
}

article a::after {
  content: "→";
  transition: transform var(--transition);
}

article a:hover,
article a:focus-visible {
  color: #fff;
  transform: translateY(-2px);
  filter: brightness(1.06);
  box-shadow: 0 8px 22px rgba(232, 93, 61, 0.42);
}

article a:hover::after {
  transform: translateX(4px);
}

/* ============ FAQ ============ */
#faq h3 {
  position: relative;
  padding: 12px 16px 12px 42px;
  margin: 12px 0 0;
  font-size: 0.98rem;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  transition: background var(--transition), border-color var(--transition), transform var(--transition);
}

#faq h3::before {
  content: "?";
  position: absolute;
  left: 14px;
  top: 50%;
  transform: translateY(-50%);
  width: 20px;
  height: 20px;
  display: grid;
  place-items: center;
  font-size: 0.72rem;
  font-weight: 800;
  color: #fff;
  background: var(--grad-text);
  border-radius: 50%;
}

#faq h3:hover {
  background: rgba(232, 93, 61, 0.06);
  border-color: var(--border-strong);
  transform: translateX(3px);
}

#faq h3 + p {
  padding: 10px 16px 4px 42px;
  margin-bottom: 6px;
  font-size: 0.92rem;
}

/* ============ HOWTO ============ */
#howto h3 {
  display: inline-block;
  padding: 4px 14px;
  margin-top: 24px;
  font-size: 0.92rem;
  color: var(--primary-dark);
  background: rgba(232, 93, 61, 0.1);
  border-radius: var(--radius-pill);
}

#howto p {
  padding-left: 4px;
}

/* ============ CONTACT ============ */
#contact p {
  font-size: 0.94rem;
  line-height: 2;
}

#contact h3:first-of-type {
  margin-top: 8px;
}

/* ============ SITEMAP / LINKS ============ */
#sitemap ul,
#links ul {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

#sitemap li,
#links li {
  margin: 0;
}

#sitemap a,
#links a {
  display: inline-block;
  padding: 8px 18px;
  font-size: 0.86rem;
  font-weight: 500;
  color: var(--text-soft);
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius-pill);
  transition: all var(--transition);
}

#sitemap a:hover,
#links a:hover,
#sitemap a:focus-visible,
#links a:focus-visible {
  color: #fff;
  background: var(--grad-text);
  border-color: transparent;
  transform: translateY(-3px);
  box-shadow: 0 8px 20px rgba(232, 93, 61, 0.32);
}

/* ============ LEGAL ============ */
#legal h2:not(:first-child) {
  margin-top: 30px;
}

#legal p {
  font-size: 0.92rem;
  color: var(--text-muted);
}

/* ============ META INFO ============ */
#meta-info {
  background: var(--bg-glass);
}

#meta-info p {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 2;
}

/* ============ FOOTER ============ */
footer {
  position: relative;
  padding: clamp(28px, 4vw, 48px) clamp(16px, 4vw, 32px) 40px;
  text-align: center;
  background: var(--bg-alt);
  border-top: 1px solid var(--border);
}

footer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: min(220px, 60%);
  height: 3px;
  border-radius: var(--radius-pill);
  background: var(--grad-text);
}

footer p {
  font-size: 0.84rem;
  color: var(--text-muted);
  margin-bottom: 6px;
}

footer p:nth-child(2) {
  font-size: 0.8rem;
  color: var(--text-muted);
  opacity: 0.82;
}

footer a {
  display: inline-block;
  margin-top: 10px;
  padding: 8px 22px;
  font-size: 0.84rem;
  font-weight: 600;
  color: #fff;
  background: var(--grad-text);
  border-radius: var(--radius-pill);
  box-shadow: 0 4px 14px rgba(232, 93, 61, 0.28);
  transition: transform var(--transition), box-shadow var(--transition), filter var(--transition);
}

footer a:hover,
footer a:focus-visible {
  color: #fff;
  transform: translateY(-3px);
  filter: brightness(1.06);
  box-shadow: 0 10px 24px rgba(232, 93, 61, 0.42);
}

/* ============ SCROLLBAR ============ */
::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}

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

::-webkit-scrollbar-thumb {
  background: linear-gradient(180deg, var(--primary-light), var(--secondary));
  border-radius: var(--radius-pill);
  border: 2px solid var(--bg);
}

::-webkit-scrollbar-thumb:hover {
  background: linear-gradient(180deg, var(--primary), var(--primary-light));
}

/* ============ RESPONSIVE: TABLET ============ */
@media (max-width: 900px) {
  header {
    padding: 12px 18px;
  }

  .brand span {
    max-width: 100%;
    white-space: normal;
    font-size: 0.68rem;
  }

  header nav ul {
    gap: 2px;
  }

  header nav a {
    padding: 6px 10px;
    font-size: 0.8rem;
  }

  section {
    border-radius: var(--radius-md);
  }

  #hero {
    border-radius: var(--radius-md);
  }
}

/* ============ RESPONSIVE: MOBILE ============ */
@media (max-width: 640px) {
  body {
    font-size: 15px;
    line-height: 1.75;
  }

  header {
    flex-direction: column;
    align-items: flex-start;
    gap: 10px;
    padding: 12px 16px;
  }

  header nav {
    width: 100%;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
  }

  header nav::-webkit-scrollbar {
    display: none;
  }

  header nav ul {
    flex-wrap: nowrap;
    width: max-content;
    padding-bottom: 2px;
  }

  header nav a {
    white-space: nowrap;
    font-size: 0.82rem;
  }

  main {
    padding: 16px 12px 40px;
  }

  section {
    padding: 18px 16px;
    margin-bottom: 20px;
    border-radius: var(--radius-sm);
  }

  #hero {
    padding: 26px 18px;
    border-radius: var(--radius-sm);
  }

  #hero h1 {
    font-size: 1.32rem;
  }

  #hero p {
    font-size: 0.9rem;
  }

  h2 {
    font-size: 1.2rem;
    padding-left: 14px;
  }

  h2::before {
    width: 4px;
  }

  h3 {
    font-size: 1rem;
  }

  article {
    padding: 14px;
    border-radius: var(--radius-sm);
  }

  article a {
    width: 100%;
    justify-content: center;
  }

  #faq h3 {
    padding: 10px 12px 10px 38px;
    font-size: 0.92rem;
  }

  #faq h3::before {
    left: 12px;
    width: 18px;
    height: 18px;
    font-size: 0.66rem;
  }

  #faq h3 + p {
    padding: 8px 12px 2px 38px;
  }

  #sitemap ul,
  #links ul {
    gap: 8px;
  }

  #sitemap a,
  #links a {
    padding: 7px 14px;
    font-size: 0.82rem;
  }

  footer {
    padding: 26px 16px 34px;
  }
}

/* ============ RESPONSIVE: SMALL MOBILE ============ */
@media (max-width: 380px) {
  .brand a {
    font-size: 1.15rem;
  }

  #hero h1 {
    font-size: 1.18rem;
  }

  header nav a {
    padding: 5px 9px;
    font-size: 0.78rem;
  }
}

/* ============ REDUCED MOTION ============ */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* ============ PRINT ============ */
@media print {
  header,
  footer,
  #hero::after {
    display: none;
  }

  body {
    background: #fff;
    color: #000;
  }

  section {
    box-shadow: none;
    border: 1px solid #ccc;
    break-inside: avoid;
  }
}