:root {
  --bg: #FAFAFA;
  --surface: #FFFFFF;
  --text-primary: #1D1D1F;
  --text-secondary: #6B7280;
  --text-tertiary: #9CA3AF;
  --accent: #2476FA;
  --accent-glow: rgba(36, 118, 250, 0.25);
  --tab-bg: #F2F2F7;
  --border: #E5E5EA;
  --radius-pill: 999px;
  --header-bg: rgba(250, 250, 250, 0.8);
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  padding: 0;
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  font-size: 16px;
  line-height: 1.7;
  color: var(--text-primary);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.page {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 120px 20px 64px;
}

.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 16px 20px 12px;
  background: var(--header-bg);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
}

.header-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.header-top {
  margin-bottom: 12px;
}

.app-logo {
  height: 24px;
  width: auto;
  display: block;
}

.header-tabs {
  display: flex;
  justify-content: center;
}

.app-label {
  font-size: 13px;
  font-weight: 400;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-tertiary);
  margin: 0 0 12px;
}

.tab-container {
  background: var(--tab-bg);
  border-radius: var(--radius-pill);
  padding: 4px;
  display: inline-flex;
  position: relative;
}

.tab-button {
  position: relative;
  z-index: 1;
  border: none;
  background: transparent;
  font-family: inherit;
  font-size: 14px;
  font-weight: 500;
  padding: 10px 24px;
  border-radius: var(--radius-pill);
  cursor: pointer;
  transition: color 0.3s ease;
  color: var(--text-secondary);
  outline: none;
  -webkit-tap-highlight-color: transparent;
}

.tab-button:hover:not(.active) {
  color: var(--text-primary);
}

.tab-button.active {
  color: white;
}

.tab-indicator {
  position: absolute;
  top: 4px;
  left: 4px;
  height: calc(100% - 8px);
  background: var(--accent);
  border-radius: var(--radius-pill);
  transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1), width 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  box-shadow: 0 2px 8px var(--accent-glow);
}

.content-wrapper {
  width: 100%;
  max-width: 680px;
  margin-top: 32px;
}

.content-panel {
  display: none;
  opacity: 0;
  transform: translateY(8px);
  animation: contentFadeIn 0.4s ease-out forwards;
}

.content-panel.active {
  display: block;
}

@keyframes contentFadeIn {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.panel-header {
  text-align: center;
  margin-bottom: 40px;
}

.panel-title {
  font-size: 26px;
  font-weight: 600;
  letter-spacing: -0.02em;
  color: var(--text-primary);
  margin: 0 0 8px;
}

.panel-date {
  font-size: 13px;
  color: var(--text-tertiary);
  margin: 0;
}

.content {
  background: var(--surface);
  border-radius: 16px;
  padding: 40px 32px;
}

.content p {
  margin: 0 0 20px;
  color: var(--text-primary);
  line-height: 1.75;
}

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

.content h2 {
  font-size: 17px;
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--text-primary);
  margin: 36px 0 12px;
}

.content h2:first-of-type {
  margin-top: 0;
}

.content a {
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s ease;
}

.content a:hover {
  border-color: var(--accent);
}

@media (max-width: 600px) {
  .page {
    padding: 100px 16px 48px;
  }

  .header {
    padding: 14px 16px 10px;
  }

  .tab-button {
    padding: 8px 18px;
    font-size: 13px;
  }

  .content {
    padding: 32px 24px;
  }

  .panel-title {
    font-size: 22px;
  }
}