/* 知径官网 · 单页样式
 * 纯静态、无外部字体/CDN；颜色与后台管理保持一致（主色 #0f766e）。
 */

:root {
  --brand: #0f766e;
  --brand-dark: #0b5f59;
  --brand-bright: #2dd4bf;
  --brand-soft: #e6f4f1;
  --deep: #053733;
  --deep-2: #0a4a44;
  --ink: #0b1f1c;
  --ink-soft: #364a46;
  --muted: #5f7570;
  --line: #e4eeeb;
  --bg: #f6faf9;
  --card: #ffffff;
  --weak: #c2410c;
  --shaky: #b45309;
  --mastered: #0f766e;
  --radius: 18px;
  --wrap: 1120px;
  --shadow-sm: 0 1px 2px rgba(9, 61, 56, 0.06);
  --shadow-md: 0 18px 48px rgba(9, 61, 56, 0.1);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 88px;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family:
    -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei",
    "Source Han Sans SC", sans-serif;
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1,
h2,
h3,
h4 {
  margin: 0;
  line-height: 1.3;
  letter-spacing: -0.015em;
  font-weight: 750;
}

p {
  margin: 0;
}

a {
  color: var(--brand-dark);
  text-decoration: none;
}

a:hover {
  text-decoration: none;
}

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

:focus-visible {
  outline: 2px solid var(--brand);
  outline-offset: 3px;
  border-radius: 8px;
}

.wrap {
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 28px;
  min-width: 0;
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--brand);
  color: #fff;
  padding: 10px 16px;
  border-radius: 0 0 10px 0;
  z-index: 30;
}

.skip-link:focus {
  left: 0;
}

/* ---------------------------------------------------------------- 顶部 */

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(255, 255, 255, 0.82);
  backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid rgba(10, 74, 68, 0.08);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 70px;
}

.brand {
  display: inline-flex;
  align-items: center;
  min-width: 0;
}

.brand-logo {
  height: 40px;
  width: auto;
}

.nav {
  display: flex;
  align-items: center;
  gap: 30px;
  font-size: 14.5px;
}

.nav a {
  color: var(--ink-soft);
  transition: color 0.18s ease;
}

.nav a:hover {
  color: var(--brand-dark);
}

.nav-cta {
  padding: 9px 18px;
  border-radius: 999px;
  border: 1px solid rgba(15, 118, 110, 0.35);
  color: var(--brand-dark);
  font-weight: 600;
  transition:
    background-color 0.18s ease,
    color 0.18s ease,
    border-color 0.18s ease;
}

.nav-cta:hover {
  background: var(--brand);
  border-color: var(--brand);
  color: #fff;
}

/* ---------------------------------------------------------------- hero */

.hero {
  position: relative;
  overflow: hidden;
  background: linear-gradient(160deg, var(--deep) 0%, #07403a 52%, var(--deep-2) 100%);
  color: #fff;
  padding: 104px 0 96px;
}

.hero-bg {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

.orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(70px);
  opacity: 0.55;
}

.orb-a {
  width: 520px;
  height: 520px;
  left: -160px;
  top: -220px;
  background: radial-gradient(circle at 30% 30%, #2dd4bf 0%, rgba(45, 212, 191, 0) 68%);
}

.orb-b {
  width: 620px;
  height: 620px;
  right: -220px;
  bottom: -320px;
  background: radial-gradient(circle at 60% 40%, #0ea5a4 0%, rgba(14, 165, 164, 0) 66%);
  opacity: 0.45;
}

.hero-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.045) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: radial-gradient(ellipse 80% 70% at 50% 30%, #000 35%, transparent 78%);
  -webkit-mask-image: radial-gradient(ellipse 80% 70% at 50% 30%, #000 35%, transparent 78%);
}

.hero-inner {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(0, 0.98fr);
  gap: 64px;
  align-items: center;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  font-size: 12.5px;
  letter-spacing: 0.24em;
  color: rgba(255, 255, 255, 0.66);
  padding: 6px 14px 6px 12px;
  border: 1px solid rgba(255, 255, 255, 0.14);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.05);
  margin-bottom: 22px;
}

.eyebrow-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--brand-bright);
  box-shadow: 0 0 12px rgba(45, 212, 191, 0.9);
}

.hero h1 {
  font-size: clamp(30px, 3.7vw, 47px);
  line-height: 1.24;
  letter-spacing: -0.03em;
  text-wrap: balance;
}

.hl {
  background: linear-gradient(100deg, #5eead4 0%, #2dd4bf 45%, #99f6e4 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.lead {
  margin-top: 22px;
  max-width: 33em;
  font-size: 16.5px;
  line-height: 1.85;
  color: rgba(255, 255, 255, 0.76);
}

.hero-actions {
  margin-top: 32px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  height: 46px;
  padding: 0 24px;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 650;
  border: 1px solid transparent;
  transition:
    transform 0.18s ease,
    background-color 0.18s ease,
    border-color 0.18s ease,
    box-shadow 0.18s ease;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn-arrow {
  transition: transform 0.18s ease;
}

.btn:hover .btn-arrow {
  transform: translateX(3px);
}

.btn-primary {
  background: var(--brand-bright);
  color: #042f2b;
  box-shadow: 0 10px 30px rgba(45, 212, 191, 0.25);
}

.btn-primary:hover {
  background: #5eead4;
  box-shadow: 0 14px 36px rgba(45, 212, 191, 0.32);
}

.btn-ghost {
  border-color: rgba(255, 255, 255, 0.26);
  color: rgba(255, 255, 255, 0.9);
  background: rgba(255, 255, 255, 0.04);
}

.btn-ghost:hover {
  border-color: rgba(255, 255, 255, 0.55);
  background: rgba(255, 255, 255, 0.09);
}

.btn-light {
  background: #fff;
  color: var(--deep);
}

.btn-light:hover {
  background: #f0fdfa;
}

.hero-facts {
  list-style: none;
  padding: 0;
  margin: 34px 0 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px 0;
  font-size: 13px;
  color: rgba(255, 255, 255, 0.55);
}

.hero-facts li {
  padding: 0 16px;
  position: relative;
}

.hero-facts li:first-child {
  padding-left: 0;
}

.hero-facts li + li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  width: 3px;
  height: 3px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.28);
  transform: translate(-50%, -50%);
}

.hero-facts b {
  color: var(--brand-bright);
  font-size: 15px;
  font-weight: 700;
  margin-right: 2px;
}

/* ---------------------------------------------------------------- hero 诊断卡 */

.hero-visual {
  position: relative;
  justify-self: end;
  width: 100%;
  max-width: 430px;
}

.diag-card {
  position: relative;
  border-radius: 22px;
  padding: 24px 24px 20px;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.1) 0%, rgba(255, 255, 255, 0.045) 100%);
  border: 1px solid rgba(255, 255, 255, 0.16);
  backdrop-filter: blur(18px);
  box-shadow: 0 30px 80px rgba(0, 20, 18, 0.45);
}

.diag-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
  padding-bottom: 16px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.12);
}

.diag-kicker {
  font-size: 11.5px;
  letter-spacing: 0.16em;
  color: rgba(255, 255, 255, 0.5);
  margin-bottom: 4px;
}

.diag-title {
  font-size: 17px;
  font-weight: 700;
  color: #fff;
}

.diag-badge {
  flex: none;
  font-size: 11.5px;
  padding: 4px 10px;
  border-radius: 999px;
  color: #042f2b;
  background: var(--brand-bright);
  font-weight: 700;
}

.trace {
  list-style: none;
  margin: 6px 0 0;
  padding: 0;
}

.trace-item {
  position: relative;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 11px 0 11px 24px;
  font-size: 14px;
  color: rgba(255, 255, 255, 0.88);
}

.trace-item::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 50%;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: rgba(5, 55, 51, 0.9);
  border: 2px solid rgba(255, 255, 255, 0.3);
  transform: translateY(-50%);
}

.trace-item:not(:last-child)::after {
  content: "";
  position: absolute;
  left: 9px;
  top: calc(50% + 8px);
  bottom: -8px;
  width: 1px;
  background: linear-gradient(rgba(255, 255, 255, 0.22), rgba(255, 255, 255, 0.06));
}

.trace-target::before {
  border-color: var(--brand-bright);
  background: var(--brand-bright);
  box-shadow: 0 0 0 4px rgba(45, 212, 191, 0.16);
}

.trace-root::before {
  border-color: #fb923c;
  background: #fb923c;
  box-shadow: 0 0 0 4px rgba(251, 146, 60, 0.16);
}

.trace-tag {
  flex: none;
  width: 32px;
  font-size: 11.5px;
  color: rgba(255, 255, 255, 0.42);
}

.trace-name {
  flex: 1 1 auto;
  min-width: 0;
}

.trace-target .trace-name {
  font-weight: 650;
  color: #fff;
}

.trace-state {
  flex: none;
  font-size: 11.5px;
  padding: 2px 9px;
  border-radius: 999px;
  border: 1px solid transparent;
}

.state-shaky {
  color: #fcd34d;
  background: rgba(251, 191, 36, 0.12);
  border-color: rgba(251, 191, 36, 0.32);
}

.state-weak {
  color: #fdba74;
  background: rgba(251, 146, 60, 0.12);
  border-color: rgba(251, 146, 60, 0.32);
}

.diag-foot {
  margin-top: 14px;
  padding-top: 16px;
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 8px;
  text-align: center;
}

.diag-stat-num {
  display: block;
  font-size: 20px;
  font-weight: 750;
  color: var(--brand-bright);
  letter-spacing: -0.02em;
}

.diag-stat-label {
  font-size: 11.5px;
  color: rgba(255, 255, 255, 0.45);
}

.diag-note {
  margin-top: 18px;
  font-size: 12.5px;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.55);
}

/* ---------------------------------------------------------------- 区块 */

.section {
  padding: 96px 0;
}

.section-tint {
  background: linear-gradient(180deg, #ffffff 0%, #f2f8f6 100%);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.section-head {
  max-width: 640px;
  margin-bottom: 44px;
}

.kicker {
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--brand);
  font-weight: 650;
  margin-bottom: 12px;
}

.section-head h2 {
  font-size: clamp(24px, 3vw, 36px);
}

.section-head p:not(.kicker) {
  margin-top: 12px;
  color: var(--muted);
  font-size: 15.5px;
}

.grid {
  display: grid;
  gap: 20px;
}

.grid-3 {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.card {
  position: relative;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: var(--shadow-sm);
  transition:
    transform 0.22s ease,
    box-shadow 0.22s ease,
    border-color 0.22s ease;
}

.card:hover {
  transform: translateY(-3px);
  border-color: rgba(15, 118, 110, 0.22);
  box-shadow: var(--shadow-md);
}

.card h3 {
  font-size: 17px;
  margin-bottom: 10px;
}

.card p {
  font-size: 14.5px;
  color: var(--muted);
  line-height: 1.8;
}

.card-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 46px;
  height: 46px;
  border-radius: 13px;
  background: var(--brand-soft);
  color: var(--brand-dark);
  margin-bottom: 18px;
}

.card-icon svg {
  width: 23px;
  height: 23px;
}

.card-tag {
  display: inline-block;
  font-size: 11.5px;
  letter-spacing: 0.08em;
  color: var(--brand);
  background: var(--brand-soft);
  border-radius: 6px;
  padding: 2px 9px;
  margin-bottom: 14px;
  font-weight: 650;
}

/* ---------------------------------------------------------------- 步骤 */

.steps {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px;
  counter-reset: step;
}

.step {
  position: relative;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 26px 24px 24px;
  box-shadow: var(--shadow-sm);
  transition:
    transform 0.22s ease,
    box-shadow 0.22s ease;
}

.step:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

.step::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 3px;
  border-radius: var(--radius) var(--radius) 0 0;
  background: linear-gradient(90deg, var(--brand) 0%, var(--brand-bright) 100%);
  opacity: 0.75;
}

.step-no {
  display: inline-block;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--brand);
  margin-bottom: 14px;
}

.step h3 {
  font-size: 16.5px;
  margin-bottom: 8px;
}

.step p {
  font-size: 14px;
  color: var(--muted);
  line-height: 1.8;
}

.states {
  margin-top: 26px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.state {
  display: flex;
  gap: 12px;
  align-items: flex-start;
  background: rgba(255, 255, 255, 0.7);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 18px 20px;
}

.state h4 {
  font-size: 15px;
  margin-bottom: 3px;
}

.state p {
  font-size: 13.5px;
  color: var(--muted);
  line-height: 1.75;
}

.dot {
  flex: none;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  margin-top: 7px;
}

.dot-mastered {
  background: var(--mastered);
  box-shadow: 0 0 0 4px rgba(15, 118, 110, 0.12);
}

.dot-shaky {
  background: var(--shaky);
  box-shadow: 0 0 0 4px rgba(180, 83, 9, 0.12);
}

.dot-weak {
  background: var(--weak);
  box-shadow: 0 0 0 4px rgba(194, 65, 12, 0.12);
}

/* ---------------------------------------------------------------- 学科 */

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

.subject {
  display: flex;
  align-items: center;
  gap: 18px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px 26px;
  box-shadow: var(--shadow-sm);
  transition:
    transform 0.22s ease,
    box-shadow 0.22s ease,
    border-color 0.22s ease;
}

.subject:hover {
  transform: translateY(-3px);
  border-color: rgba(15, 118, 110, 0.22);
  box-shadow: var(--shadow-md);
}

.subject-mark {
  flex: none;
  width: 54px;
  height: 54px;
  border-radius: 15px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 21px;
  font-weight: 700;
  color: #fff;
  background: linear-gradient(145deg, var(--brand) 0%, #0b8f84 60%, var(--brand-bright) 100%);
  box-shadow: 0 10px 24px rgba(15, 118, 110, 0.25);
}

.subject h3 {
  font-size: 16.5px;
  margin-bottom: 4px;
}

.subject p {
  font-size: 14px;
  color: var(--muted);
}

.note {
  margin-top: 24px;
  font-size: 13.5px;
  color: var(--muted);
  max-width: 62em;
}

/* ---------------------------------------------------------------- 原则 */

.principle {
  max-width: 820px;
}

.principle blockquote {
  margin: 0;
  padding-left: 24px;
  border-left: 3px solid var(--brand-bright);
}

.principle p:first-child {
  font-size: clamp(22px, 2.8vw, 32px);
  font-weight: 750;
  letter-spacing: -0.02em;
  line-height: 1.45;
  color: var(--ink);
}

.principle-sub {
  margin-top: 14px;
  color: var(--muted);
  font-size: 15.5px;
  line-height: 1.85;
}

/* ---------------------------------------------------------------- CTA */

.cta-band {
  position: relative;
  overflow: hidden;
  background: linear-gradient(120deg, var(--deep) 0%, #07403a 55%, #0b5f59 100%);
  color: #fff;
  padding: 64px 0;
}

.cta-band::after {
  content: "";
  position: absolute;
  right: -120px;
  top: -160px;
  width: 420px;
  height: 420px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(45, 212, 191, 0.35) 0%, rgba(45, 212, 191, 0) 70%);
  filter: blur(20px);
  pointer-events: none;
}

.cta-inner {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
}

.cta-inner h2 {
  font-size: clamp(22px, 2.6vw, 30px);
}

.cta-inner p {
  margin-top: 8px;
  color: rgba(255, 255, 255, 0.6);
  font-size: 14.5px;
}

/* ---------------------------------------------------------------- 页脚 */

.site-footer {
  background: #fff;
  border-top: 1px solid var(--line);
  padding: 44px 0 52px;
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  justify-content: space-between;
  gap: 32px;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 14px;
  min-width: 0;
}

.footer-mark {
  width: 42px;
  height: 42px;
  border-radius: 11px;
}

.footer-title {
  font-weight: 750;
}

.footer-sub {
  font-size: 12.5px;
  color: var(--muted);
}

.footer-nav {
  display: flex;
  gap: 26px;
  font-size: 14px;
}

.footer-nav a {
  color: var(--ink-soft);
}

.footer-meta {
  font-size: 12.5px;
  color: var(--muted);
  text-align: right;
}

.footer-meta .muted {
  color: #93a19d;
}

.footer-legal {
  margin-top: 8px;
  font-size: 12px;
  color: #93a19d;
}

.footer-legal a {
  color: #93a19d;
  transition: color 0.18s ease;
}

.footer-legal a:hover {
  color: var(--brand-dark);
}

.footer-sep {
  margin: 0 8px;
  color: #c8d3d0;
}

/* ---------------------------------------------------------------- 滚动淡入 */

.js .reveal {
  opacity: 0;
  transform: translateY(18px);
  transition:
    opacity 0.6s ease,
    transform 0.6s cubic-bezier(0.22, 1, 0.36, 1);
  transition-delay: var(--delay, 0ms);
  will-change: opacity, transform;
}

.js .reveal.is-visible {
  opacity: 1;
  transform: none;
}

/* ---------------------------------------------------------------- 响应式 */

@media (max-width: 980px) {
  .hero {
    padding: 72px 0 68px;
  }

  .hero-inner {
    grid-template-columns: minmax(0, 1fr);
    gap: 44px;
  }

  .hero-visual {
    justify-self: stretch;
    max-width: 520px;
  }

  .grid-3,
  .steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .states {
    grid-template-columns: minmax(0, 1fr);
  }

  .cta-inner {
    flex-direction: column;
    align-items: flex-start;
  }
}

@media (max-width: 720px) {
  .wrap {
    padding: 0 20px;
  }

  .nav a:not(.nav-cta) {
    display: none;
  }

  .hero {
    padding: 56px 0 56px;
  }

  .hero-facts {
    margin-top: 28px;
  }

  .section {
    padding: 64px 0;
  }

  .section-head {
    margin-bottom: 32px;
  }

  .grid-3,
  .steps,
  .subjects {
    grid-template-columns: minmax(0, 1fr);
  }

  .diag-card {
    padding: 20px 18px 16px;
  }

  .footer-nav {
    gap: 18px;
  }

  .footer-meta {
    text-align: left;
  }
}

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

  .btn,
  .btn-arrow,
  .card,
  .step,
  .subject {
    transition: none;
  }

  .btn:hover,
  .card:hover,
  .step:hover,
  .subject:hover {
    transform: none;
  }
}

/* 打印或导出 PDF 时不要把未滚动到的区块藏起来 */
@media print {
  .js .reveal {
    opacity: 1 !important;
    transform: none !important;
  }
}