/* ============================================================
   KAIYUN全站 — Site CSS  /assets/site.css
   运动数据控制台 · Sports Data Console
   ============================================================ */

/* ---------- Reset & Base ---------- */
*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

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

body {
  font-family: 'Open Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto,
    'Noto Sans SC', 'Microsoft YaHei', sans-serif;
  font-size: 16px;
  line-height: 1.7;
  color: #0D0D0D;
  background-color: #0A1F44;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

img,
picture,
video,
canvas,
svg {
  display: block;
  max-width: 100%;
}

input,
button,
textarea,
select {
  font: inherit;
  color: inherit;
}

button {
  cursor: pointer;
  background: none;
  border: none;
}

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

ul,
ol {
  list-style: none;
}

/* ---------- CSS Variables ---------- */
:root {
  /* Palette */
  --c-blue: #0A1F44;
  --c-midblue: #1E3A5F;
  --c-gold: #FFD700;
  --c-orange: #FF6B35;
  --c-paper: #F5F0E6;
  --c-ink: #0D0D0D;
  --c-white: #FFFFFF;
  --c-gray: #E0E0E0;

  /* Fonts */
  --f-heading: 'Montserrat Black', 'Arial Black', 'Noto Sans SC', 'Microsoft YaHei', sans-serif;
  --f-body: 'Open Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto,
    'Noto Sans SC', 'Microsoft YaHei', sans-serif;
  --f-mono: ui-monospace, SFMono-Regular, Menlo, Consolas, 'Courier New', monospace;

  /* Type scale */
  --fs-display: clamp(40px, 7vw, 64px);
  --fs-h1: clamp(32px, 5vw, 40px);
  --fs-h2: clamp(24px, 4vw, 28px);
  --fs-h3: 20px;
  --fs-body: 16px;
  --fs-caption: 12px;

  /* Radius */
  --r-lg: 28px;
  --r-md: 18px;
  --r-sm: 10px;
  --r-pill: 999px;

  /* Shadows */
  --sh-card: 0 8px 30px rgba(10, 31, 68, 0.12);
  --sh-hover: 0 18px 60px rgba(10, 31, 68, 0.2);
  --sh-header: 0 4px 24px rgba(0, 0, 0, 0.35);

  /* Layout */
  --container: 1280px;
  --container-wide: 1560px;
  --container-narrow: 860px;
  --header-h: 76px;

  /* Motion */
  --t-fast: 0.2s ease;
  --t-med: 0.35s ease;
  --t-slow: 0.6s cubic-bezier(0.22, 1, 0.36, 1);
}

/* ---------- Focus-visible ---------- */
a:focus-visible,
button:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible {
  outline: 3px solid var(--c-gold);
  outline-offset: 3px;
  border-radius: 4px;
}

#main-content:focus-visible {
  outline: 3px solid var(--c-gold);
  outline-offset: -3px;
}

/* ---------- Skip Link ---------- */
.skip-link {
  position: fixed;
  top: -100px;
  left: 16px;
  z-index: 300;
  padding: 12px 24px;
  background: var(--c-gold);
  color: var(--c-blue);
  font-family: var(--f-body);
  font-size: 14px;
  font-weight: 700;
  border-radius: var(--r-pill);
  transition: top var(--t-fast);
}

.skip-link:focus-visible {
  top: 12px;
  outline: 3px solid var(--c-white);
  outline-offset: 2px;
}

/* ---------- Container System ---------- */
.container,
.container--wide,
.container--narrow {
  width: 100%;
  margin-left: auto;
  margin-right: auto;
  padding-left: 24px;
  padding-right: 24px;
}

.container {
  max-width: var(--container);
}

.container--wide {
  max-width: var(--container-wide);
}

.container--narrow {
  max-width: var(--container-narrow);
}

/* ---------- Section System ---------- */
.section {
  padding: clamp(60px, 10vw, 110px) 0;
}

.section--blue {
  background: var(--c-blue);
  color: var(--c-white);
}

.section--paper {
  background: var(--c-paper);
  color: var(--c-blue);
}

.section--ink {
  background: var(--c-ink);
  color: var(--c-white);
}

#main-content {
  display: block;
  min-height: 60vh;
}

/* ---------- Header ---------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: linear-gradient(180deg, rgba(10, 31, 68, 0.92) 0%, rgba(10, 31, 68, 0.5) 60%, rgba(10, 31, 68, 0) 100%);
  transition: background var(--t-med), box-shadow var(--t-med);
}

.site-header.is-scrolled {
  background: rgba(10, 31, 68, 0.97);
  box-shadow: var(--sh-header);
}

.site-header.is-scrolled::after {
  content: '';
  position: absolute;
  bottom: -1px;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, var(--c-gold) 0%, var(--c-orange) 40%, transparent 80%);
}

.site-header__bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-h);
  position: relative;
  z-index: 10;
}

/* ---------- Logo ---------- */
.site-logo {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  flex-shrink: 0;
}

.site-logo__mark {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  font-family: var(--f-heading);
  font-weight: 900;
  font-size: 22px;
  color: var(--c-blue);
}

.site-logo__mark::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, var(--c-gold) 0%, #FFC107 100%);
  border-radius: 12px;
  transform: rotate(45deg);
  box-shadow: 0 4px 12px rgba(255, 215, 0, 0.35);
  z-index: -1;
}

.site-logo__text {
  font-family: var(--f-heading);
  font-size: 24px;
  font-weight: 900;
  line-height: 1.1;
  color: var(--c-white);
  letter-spacing: 0.02em;
  white-space: nowrap;
}

.site-logo__text em {
  font-style: normal;
  color: var(--c-gold);
}

.site-logo--footer .site-logo__mark::before {
  box-shadow: none;
}

/* ---------- Desktop Navigation ---------- */
.site-nav__list {
  display: flex;
  align-items: center;
  gap: 4px;
}

.site-nav__link {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  padding: 10px 14px;
  color: rgba(255, 255, 255, 0.85);
  font-family: var(--f-body);
  font-size: 14px;
  font-weight: 600;
  border-radius: var(--r-pill);
  transition: color var(--t-fast), background var(--t-fast);
  position: relative;
}

.site-nav__link:hover {
  color: var(--c-gold);
  background: rgba(255, 255, 255, 0.08);
}

.site-nav__link[aria-current="page"] {
  color: var(--c-white);
  background: rgba(255, 215, 0, 0.12);
}

.site-nav__link[aria-current="page"]::after {
  content: '';
  position: absolute;
  left: 18px;
  right: 18px;
  bottom: 4px;
  height: 2px;
  background: var(--c-gold);
  border-radius: 2px;
}

.site-nav__num {
  font-family: var(--f-mono);
  font-size: 11px;
  color: var(--c-gold);
  opacity: 0.7;
}

.site-nav__label {
  font-size: 14px;
  letter-spacing: 0.02em;
}

/* ---------- Mobile Nav Toggle ---------- */
.site-nav-toggle {
  display: none;
}

/* ---------- Mobile Navigation ---------- */
@media (max-width: 900px) {
  .site-nav-toggle {
    display: inline-flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 5px;
    width: 44px;
    height: 44px;
    padding: 10px;
    border-radius: 12px;
    background: rgba(10, 31, 68, 0.6);
    border: 1px solid rgba(255, 255, 255, 0.15);
    z-index: 30;
  }

  .site-nav-toggle__bar {
    display: block;
    height: 2px;
    width: 22px;
    background: var(--c-white);
    border-radius: 2px;
    transition: transform var(--t-med), opacity var(--t-fast);
  }

  .site-nav-toggle.is-active .site-nav-toggle__bar:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
  }

  .site-nav-toggle.is-active .site-nav-toggle__bar:nth-child(2) {
    opacity: 0;
  }

  .site-nav-toggle.is-active .site-nav-toggle__bar:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
  }

  .site-nav {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    background: var(--c-blue);
    padding: calc(var(--header-h) + 20px) 28px 40px;
    z-index: 20;
    opacity: 0;
    visibility: hidden;
    transform: translateX(100%);
    transition: opacity var(--t-med), transform var(--t-med), visibility var(--t-med);
    overflow-y: auto;
    overscroll-behavior: contain;
  }

  .site-nav[data-open="true"] {
    opacity: 1;
    visibility: visible;
    transform: translateX(0);
  }

  body.nav-open .site-header {
    background: var(--c-blue);
  }

  body.nav-open {
    overflow: hidden;
  }

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 8px;
    max-width: 480px;
    margin: 0 auto;
  }

  .site-nav__item {
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  }

  .site-nav__link {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 18px 12px;
    font-size: 18px;
    border-radius: var(--r-md);
  }

  .site-nav__num {
    font-size: 14px;
    opacity: 1;
  }

  .site-nav__link[aria-current="page"] {
    background: rgba(255, 215, 0, 0.1);
    border-left: 3px solid var(--c-gold);
    border-radius: 0 var(--r-md) var(--r-md) 0;
  }

  .site-nav__link[aria-current="page"]::after {
    display: none;
  }
}

/* ---------- Scroll Progress ---------- */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  width: 0;
  background: linear-gradient(90deg, var(--c-gold), var(--c-orange));
  z-index: 200;
  pointer-events: none;
  border-radius: 0 3px 3px 0;
}

/* ---------- Back to Top ---------- */
.back-to-top {
  position: fixed;
  right: 24px;
  bottom: 24px;
  z-index: 90;
  width: 52px;
  height: 52px;
  border-radius: 50%;
  background: var(--c-orange);
  color: var(--c-white);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 8px 24px rgba(255, 107, 53, 0.45);
  opacity: 0;
  visibility: hidden;
  transform: translateY(16px);
  transition: opacity var(--t-med), transform var(--t-med), visibility var(--t-med);
}

.back-to-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover {
  background: var(--c-gold);
  color: var(--c-blue);
  transform: translateY(-4px);
}

.back-to-top__icon {
  font-size: 24px;
  line-height: 1;
  font-family: var(--f-body);
}

/* ---------- Footer ---------- */
.site-footer {
  position: relative;
  background: var(--c-blue);
  color: rgba(255, 255, 255, 0.85);
  margin-top: 80px;
}

.site-footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 6px;
  background: linear-gradient(135deg, var(--c-gold) 0%, var(--c-gold) 60%, var(--c-orange) 60%, var(--c-orange) 100%);
  z-index: 2;
}

.site-footer__grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1.2fr;
  gap: 48px;
  padding-top: 64px;
  padding-bottom: 48px;
}

.site-footer__brand {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 16px;
}

.site-footer__statement {
  color: rgba(255, 255, 255, 0.65);
  font-size: 14px;
  line-height: 1.8;
  max-width: 340px;
}

.site-footer__slogan {
  font-family: var(--f-mono);
  font-size: 13px;
  letter-spacing: 0.14em;
  color: var(--c-gold);
  text-transform: uppercase;
  padding-top: 4px;
  border-top: 1px solid rgba(255, 215, 0, 0.3);
}

.site-footer__heading {
  font-family: var(--f-heading);
  font-size: 14px;
  font-weight: 900;
  color: var(--c-gold);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  margin-bottom: 20px;
  padding-bottom: 10px;
  position: relative;
}

.site-footer__heading::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: 0;
  width: 32px;
  height: 2px;
  background: linear-gradient(90deg, var(--c-gold), var(--c-orange));
  border-radius: 2px;
}

.site-footer__links {
  display: grid;
  gap: 12px;
}

.site-footer__link {
  display: inline-block;
  color: rgba(255, 255, 255, 0.7);
  font-size: 14px;
  padding: 2px 0;
  transition: color var(--t-fast), transform var(--t-fast);
}

.site-footer__link::before {
  content: '›';
  color: var(--c-orange);
  margin-right: 8px;
  font-weight: 700;
  font-family: var(--f-mono);
}

.site-footer__link:hover {
  color: var(--c-gold);
  transform: translateX(4px);
}

.site-footer__cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 16px;
  padding: 10px 20px;
  background: var(--c-gold);
  color: var(--c-blue);
  font-weight: 700;
  font-size: 14px;
  border-radius: var(--r-pill);
  transition: background var(--t-fast), transform var(--t-fast), color var(--t-fast);
}

.site-footer__cta:hover {
  background: var(--c-orange);
  color: var(--c-white);
  transform: translateY(-2px);
}

.site-footer__cta-arrow {
  font-family: var(--f-mono);
  transition: transform var(--t-fast);
}

.site-footer__cta:hover .site-footer__cta-arrow {
  transform: translateX(4px);
}

.site-footer__contact {
  display: grid;
  gap: 12px;
}

.site-footer__contact-item {
  font-size: 14px;
  color: rgba(255, 255, 255, 0.7);
  padding-left: 20px;
  position: relative;
  line-height: 1.6;
}

.site-footer__contact-item::before {
  content: '';
  position: absolute;
  left: 0;
  top: 10px;
  width: 6px;
  height: 6px;
  background: var(--c-gold);
  transform: rotate(45deg);
}

.site-footer__bottom {
  background: var(--c-ink);
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  padding: 20px 0;
}

.site-footer__bottom-inner {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
}

.site-footer__copyright,
.site-footer__icp {
  font-family: var(--f-mono);
  font-size: 13px;
  color: rgba(255, 255, 255, 0.5);
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 14px 30px;
  border-radius: var(--r-pill);
  font-family: var(--f-body);
  font-size: 15px;
  font-weight: 700;
  line-height: 1;
  cursor: pointer;
  border: 2px solid transparent;
  transition: background var(--t-med), color var(--t-med), transform var(--t-med), box-shadow var(--t-med);
}

.btn--primary {
  background: var(--c-gold);
  color: var(--c-blue);
  box-shadow: 0 8px 24px rgba(255, 215, 0, 0.3);
}

.btn--primary:hover {
  background: var(--c-orange);
  color: var(--c-white);
  box-shadow: 0 12px 32px rgba(255, 107, 53, 0.35);
  transform: translateY(-2px);
}

.btn--ghost {
  background: transparent;
  color: var(--c-gold);
  border-color: var(--c-gold);
}

.btn--ghost:hover {
  background: rgba(255, 215, 0, 0.1);
  transform: translateY(-2px);
}

/* ---------- Cards ---------- */
.card {
  background: var(--c-paper);
  border-radius: var(--r-lg);
  padding: 32px;
  box-shadow: var(--sh-card);
  color: var(--c-blue);
}

.card--data {
  background: linear-gradient(145deg, var(--c-blue), var(--c-midblue));
  color: var(--c-white);
  border: 1px solid rgba(255, 215, 0, 0.2);
}

.card--hover {
  transition: transform var(--t-med), box-shadow var(--t-med);
}

.card--hover:hover {
  transform: translateY(-6px);
  box-shadow: var(--sh-hover);
}

/* ---------- Data Panel ---------- */
.data-label {
  display: block;
  font-family: var(--f-mono);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--c-gold);
  margin-bottom: 8px;
}

.data-value {
  display: block;
  font-family: var(--f-heading);
  font-size: 42px;
  font-weight: 900;
  line-height: 1.1;
  color: var(--c-white);
}

/* ---------- Badges ---------- */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 14px;
  border-radius: var(--r-pill);
  font-family: var(--f-body);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.06em;
  line-height: 1.4;
}

.badge--gold {
  background: var(--c-gold);
  color: var(--c-blue);
}

.badge--orange {
  background: var(--c-orange);
  color: var(--c-white);
}

.badge--blue {
  background: var(--c-blue);
  color: var(--c-white);
  border: 1px solid rgba(255, 255, 255, 0.25);
}

/* ---------- Tags ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  padding: 8px 18px;
  border-radius: var(--r-pill);
  font-family: var(--f-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--c-blue);
  background: var(--c-paper);
  border: 1px solid transparent;
  transition: border-color var(--t-fast), background var(--t-fast);
}

.tag:hover {
  border-color: var(--c-gold);
  background: rgba(255, 215, 0, 0.1);
}

/* ---------- Headings ---------- */
.heading {
  font-family: var(--f-heading);
  font-weight: 900;
  line-height: 1.2;
  color: inherit;
}

.heading--display {
  font-size: var(--fs-display);
  letter-spacing: -0.02em;
}

.heading--h1 {
  font-size: var(--fs-h1);
}

.heading--h2 {
  font-size: var(--fs-h2);
}

.heading--h3 {
  font-size: var(--fs-h3);
}

/* ---------- Chapter Numbers ---------- */
.chapter-num {
  font-family: var(--f-mono);
  font-size: clamp(56px, 10vw, 120px);
  font-weight: 700;
  line-height: 1;
  color: rgba(255, 215, 0, 0.25);
  letter-spacing: -0.04em;
  user-select: none;
}

/* ---------- Breadcrumb ---------- */
.breadcrumb {
  padding: calc(var(--header-h) + 32px) 0 16px;
}

.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
}

.breadcrumb__item {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--f-mono);
  font-size: 13px;
  color: rgba(255, 255, 255, 0.6);
}

.breadcrumb__link {
  color: rgba(255, 255, 255, 0.6);
  transition: color var(--t-fast);
}

.breadcrumb__link:hover {
  color: var(--c-gold);
}

.breadcrumb__sep {
  color: var(--c-gold);
  opacity: 0.5;
}

/* ---------- Body Content ---------- */
.body-content {
  color: var(--c-blue);
  line-height: 1.85;
}

.body-content > * + * {
  margin-top: 1.2em;
}

.body-content h2,
.body-content h3 {
  font-family: var(--f-heading);
  color: var(--c-blue);
  margin-top: 1.6em;
}

.body-content p {
  color: rgba(13, 13, 13, 0.85);
}

.body-content ul {
  padding: 0;
}

.body-content ul li {
  position: relative;
  padding-left: 20px;
  margin-bottom: 8px;
}

.body-content ul li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 10px;
  width: 8px;
  height: 8px;
  background: var(--c-gold);
  transform: rotate(45deg);
}

/* ---------- Image Frames ---------- */
.img-frame {
  position: relative;
  background: var(--c-midblue);
  border-radius: var(--r-lg);
  overflow: hidden;
  isolation: isolate;
}

.img-frame::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(160deg, rgba(10, 31, 68, 0.35), rgba(255, 107, 53, 0.15));
  z-index: 1;
  pointer-events: none;
}

.img-frame::after {
  content: 'IMG · 赛事影像待补充';
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--f-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: rgba(255, 255, 255, 0.45);
  z-index: 2;
  text-transform: uppercase;
  pointer-events: none;
}

.img-frame img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  z-index: 3;
}

.img-frame--hero {
  aspect-ratio: 21 / 9;
  border-radius: 0;
}

.img-frame--card {
  aspect-ratio: 16 / 10;
  border-radius: var(--r-md);
}

/* ---------- Slant Band ---------- */
.slant-band {
  height: 60px;
  background: linear-gradient(135deg, var(--c-gold) 50%, var(--c-orange) 50%);
}

/* ---------- Reveal Animation ---------- */
[data-reveal] {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity var(--t-slow), transform var(--t-slow);
}

[data-reveal].is-revealed {
  opacity: 1;
  transform: translateY(0);
}

/* ---------- Responsive Adjustments ---------- */
@media (max-width: 1199px) {
  .site-footer__grid {
    grid-template-columns: 1fr 1fr;
    gap: 40px;
  }
}

@media (max-width: 640px) {
  .container,
  .container--wide,
  .container--narrow {
    padding-left: 18px;
    padding-right: 18px;
  }

  .site-header__bar {
    height: 64px;
  }

  :root {
    --header-h: 64px;
  }

  .site-logo__mark {
    width: 38px;
    height: 38px;
    font-size: 19px;
  }

  .site-logo__text {
    font-size: 20px;
  }

  .site-footer__grid {
    grid-template-columns: 1fr;
    gap: 32px;
    padding-top: 48px;
  }

  .site-footer__bottom-inner {
    flex-direction: column;
    text-align: center;
  }

  .back-to-top {
    right: 16px;
    bottom: 16px;
    width: 46px;
    height: 46px;
  }
}

@media (max-width: 560px) {
  .site-footer__grid {
    grid-template-columns: 1fr;
  }
}

/* ---------- Reduced Motion ---------- */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  [data-reveal] {
    opacity: 1;
    transform: none;
    transition: none;
  }
}