* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }
  
  html {
    scroll-behavior: smooth;
  }
  
  body {
    font-family: -apple-system, BlinkMacSystemFont, sans-serif;
    color: white;
    line-height: 1.6;
  
    background-color: #0b1120;
  
    background-image:
      radial-gradient(circle at top left, rgba(139,92,246,0.22), transparent 32%),
      radial-gradient(circle at top right, rgba(59,130,246,0.18), transparent 34%),
      linear-gradient(180deg, #0b1120 0%, #0f172a 45%, #0b1120 100%);
  
    background-size: 100% 1400px;
    background-repeat: no-repeat;
    background-attachment: scroll;
  }
  
  /* Header */
  .site-header {
    width: 100%;
    padding: 24px 8%;
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: sticky;
    top: 0;
    backdrop-filter: blur(12px);
    background: rgba(15, 23, 42, 0.7);
    border-bottom: none;
    z-index: 5000;
    transition: transform 0.3s ease;
  }
  
  .logo {
    text-decoration: none;
    color: white;
    font-size: 1.4rem;
    font-weight: 700;
  }
  
  .logo span {
    color: #8b5cf6;
  }
  
  nav {
    display: flex;
    gap: 24px;
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
  }
  
  nav a {
    color: rgba(255,255,255,0.8);
    text-decoration: none;
    font-weight: 700;
    font-size: 1rem;
    transition: 0.3s;
  }
  
  nav a:hover {
    color: white;
  }
  
  /* Mobile menu */
  .menu-toggle {
    display: none;
    background: none;
    border: none;
    color: white;
    font-size: 1.8rem;
    cursor: pointer;
  }
  
  .menu-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.55);
    opacity: 0;
    pointer-events: none;
    transition: 0.3s ease;
    z-index: 3000;
  }
  
  .menu-overlay.open {
    opacity: 1;
    pointer-events: auto;
  }
  
  .header-hidden {
    transform: translateY(-100%);
  }
  
  /* Hero */
  .hero {
    min-height: auto;
    padding: 90px 8% 70px;
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    position: relative;
    overflow: visible;
    background: transparent;
  }
  
  .badge {
    padding: 10px 18px;
    border-radius: 999px;
    background: rgba(255,255,255,0.08);
    border: 1px solid rgba(255,255,255,0.08);
    margin-bottom: 24px;
    font-size: 0.95rem;
  }
  
  .hero h1 {
    font-size: 4rem;
    max-width: 900px;
    line-height: 1.1;
    margin-bottom: 24px;
  }
  
  .hero-text {
    max-width: 700px;
    font-size: 1.2rem;
    color: rgba(255,255,255,0.7);
    margin-bottom: 42px;
  }
  
  /* Symbol tool */
  .symbol-tool-card {
    width: 100%;
    max-width: 980px;
  }
  
  .sticky-selection-wrap {
    position: sticky;
    top: 92px;
    z-index: 50;
    margin-bottom: 24px;
  }
  
  .selection-card {
    width: 100%;
    max-width: 760px;
    min-height: 78px;
    margin: 0 auto;
    padding: 10px 132px 10px 18px;
    border-radius: 22px;
    background: rgba(255,255,255,0.05);
    border: 1px solid rgba(255,255,255,0.08);
    backdrop-filter: blur(18px);
    position: relative;
  }
  
  textarea {
    width: 100%;
    height: 48px;
    min-height: 48px;
    border: none;
    outline: none;
    resize: none;
    padding: 11px 0;
    border-radius: 0;
    background: transparent;
    color: white;
    font-size: 1rem;
    margin: 0;
  }
  
  textarea::placeholder {
    color: rgba(255,255,255,0.42);
  }
  
  .copy-selection-btn {
    position: absolute;
    right: 12px;
    top: 50%;
    transform: translateY(-50%);
  
    min-width: 92px;
  
    border: none;
    cursor: pointer;
  
    padding: 10px 15px;
    border-radius: 14px;
  
    background: linear-gradient(135deg,#8b5cf6,#6366f1);
  
    color: white;
    font-size: 0.95rem;
    font-weight: 800;
  
    z-index: 2;
  }
  
  .clear-selection-btn {
    position: absolute;
    right: 108px;
    top: 50%;
    transform: translateY(-50%);
  
    width: 32px;
    height: 32px;
  
    border: none;
    border-radius: 50%;
  
    background: rgba(255,255,255,0.08);
  
    color: rgba(255,255,255,0.8);
  
    font-size: 1.35rem;
  
    cursor: pointer;
  
    z-index: 2;
  }
  
  .copy-message {
    min-height: 22px;
    margin-top: 18px;
    color: rgba(255,255,255,0.7);
    font-size: 0.95rem;
  }
  
  .symbol-categories {
    display: flex;
    gap: 10px;
    margin: 22px 0 18px;
    overflow-x: auto;
    scrollbar-width: none;
    padding-bottom: 6px;
  }
  
  .symbol-categories::-webkit-scrollbar {
    display: none;
  }
  
  .symbol-filter {
    flex: 0 0 auto;
    border: 1px solid rgba(255,255,255,0.1);
    border-radius: 999px;
    padding: 9px 14px;
    background: rgba(255,255,255,0.04);
    color: rgba(255,255,255,0.75);
    font-weight: 700;
    cursor: pointer;
    transition: 0.2s ease;
  }
  
  .symbol-filter:hover,
  .symbol-filter.active {
    color: white;
    background: linear-gradient(135deg,#8b5cf6,#6366f1);
    border-color: transparent;
  }
  
  .symbol-grid {
    width: 100%;
    display: grid;
    grid-template-columns: repeat(10, 1fr);
    gap: 14px;
  }
  
  .symbol-item {
    height: 78px;
    border-radius: 18px;
    background: rgba(255,255,255,0.04);
    border: 1px solid rgba(255,255,255,0.08);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.85rem;
    cursor: pointer;
    transition: 0.2s ease;
  }
  
  .symbol-item:hover {
    transform: translateY(-2px);
    background: rgba(255,255,255,0.06);
    border-color: rgba(139,92,246,0.5);
  }
  
  /* Sections */
  .section {
    padding: 70px 8%;
    background: transparent;
  }
  
  .section h2 {
    font-size: 2.6rem;
    margin-bottom: 16px;
    text-align: center;
  }
  
  .section-intro {
    text-align: center;
    max-width: 700px;
    margin: 0 auto 42px;
    color: rgba(255,255,255,0.7);
  }
  
  .grid,
  .steps {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
  }
  
  .card,
  .step {
    padding: 28px;
    border-radius: 24px;
    background: rgba(255,255,255,0.04);
    border: 1px solid rgba(255,255,255,0.08);
  }
  
  .card h3,
  .step h3 {
    margin-bottom: 10px;
  }
  
  .card p,
  .step p {
    color: rgba(255,255,255,0.7);
  }
  
  .steps {
    margin-top: 36px;
  }
  
  .step span {
    width: 42px;
    height: 42px;
    border-radius: 50%;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: #8b5cf6;
    font-weight: bold;
    margin-bottom: 20px;
  }
  
  .faq {
    max-width: 900px;
    margin: auto;
    padding-top: 70px;
  }
  
  details {
    padding: 24px;
    border-radius: 20px;
    background: rgba(255,255,255,0.04);
    border: 1px solid rgba(255,255,255,0.08);
    margin-bottom: 20px;
  }
  
  summary {
    cursor: pointer;
    font-weight: 600;
    font-size: 1.05rem;
  }
  
  details p {
    margin-top: 16px;
    color: rgba(255,255,255,0.7);
  }
  
  /* Footer */
  footer {
    padding: 40px;
    text-align: center;
    color: rgba(255,255,255,0.5);
  }
  
  /* Tablet */
  @media (max-width: 900px) {
    .symbol-grid {
      grid-template-columns: repeat(5, 1fr);
    }
  
    .grid,
    .steps {
      grid-template-columns: 1fr;
    }
  }
  
  /* Mobile */
  @media (max-width: 768px) {
    .site-header {
      padding: 20px 8%;
    }
  
    .menu-toggle {
      display: block;
      position: relative;
      z-index: 3001;
    }
  
    nav {
      position: fixed;
      top: 0;
      right: 0;
      left: auto;
      width: 82vw;
      max-width: 260px;
      height: 100vh;
      padding: 120px 32px 32px;
      background: #0b1020;
      border-left: 1px solid rgba(255,255,255,0.08);
      display: flex;
      flex-direction: column;
      gap: 24px;
      transform: translateX(100%);
      transition: transform 0.3s ease;
      z-index: 4000;
    }
  
    nav.open {
      transform: translateX(0);
    }
  
    nav a {
      color: white;
      text-decoration: none;
      font-size: 1.25rem;
      font-weight: 800;
      opacity: 1;
    }
  
    .hero {
        padding: 42px 8% 44px;
      }
    
      .hero h1 {
        font-size: 2rem;
        line-height: 1.1;
        margin-bottom: 16px;
      }
    
      .hero-text {
        font-size: 1rem;
        line-height: 1.7;
        margin-bottom: 28px;
      }

    .badge {
        margin-bottom: 18px;
        font-size: 0.85rem;
      }
  
    .sticky-selection-wrap {
      top: 92px;
    }
  
    .selection-card {
      min-height: 78px;
      padding: 10px 124px 10px 16px;
    }
  
    textarea {
      height: 48px;
      min-height: 48px;
      font-size: 1rem;
    }
  
    .copy-selection-btn {
        right: 12px;
        min-width: 92px;
      }
    
      .clear-selection-btn {
        right: 116px;
      }
  
    .symbol-grid {
      grid-template-columns: repeat(3, 1fr);
      gap: 12px;
    }
  
    .symbol-item {
      height: 78px;
      font-size: 1.7rem;
    }
  
    .section {
      padding: 48px 8%;
    }
  
    .section h2 {
      font-size: 2rem;
    }
  
    .section-intro {
      margin-bottom: 28px;
    }
  
    .grid,
    .steps {
      gap: 18px;
      margin-top: 28px;
    }
  
    .card,
    .step {
      padding: 24px;
    }
  
    .faq {
      padding-top: 48px;
    }
  }

  .site-footer {
    margin-top: 80px;
    padding: 70px 8% 36px;
  
    border-top: 1px solid rgba(255,255,255,0.08);
  
    background: linear-gradient(
      180deg,
      rgba(255,255,255,0.02),
      rgba(255,255,255,0.01)
    );
  }
  
  .footer-content,
  .footer-bottom {
    max-width: 1200px;
    margin: 0 auto;
  }
  
  .footer-content {
    display: flex;
    align-items: flex-start;
  
    gap: 120px;
  }
  
  .footer-brand {
    max-width: 260px;
  
    text-align: left;
  }
  
  .footer-logo {
    display: inline-block;
  
    margin-bottom: 18px;
  
    color: white;
    text-decoration: none;
  
    font-size: 1.5rem;
    font-weight: 800;
  }
  
  .footer-logo span {
    color: #8b5cf6;
  }
  
  .footer-brand p {
    color: rgba(255,255,255,0.65);
    line-height: 1.8;
  }
  
  .footer-links {
    min-width: 220px;
  
    margin-left: -40px;
  
    display: flex;
    flex-direction: column;
    align-items: flex-start;
  
    gap: 12px;
  
    text-align: left;
  }
  
  .footer-links h3 {
    margin-bottom: 8px;
  
    color: white;
  
    font-size: 1rem;
    font-weight: 700;
  }
  
  .footer-links a {
    color: rgba(255,255,255,0.68);
  
    text-decoration: none;
  
    transition: 0.2s ease;
  }
  
  .footer-links a:hover {
    color: white;
  }
  
  .footer-bottom {
    margin-top: 60px;
    padding-top: 24px;
  
    border-top: 1px solid rgba(255,255,255,0.06);
  
    text-align: center;
  
    color: rgba(255,255,255,0.45);
  
    font-size: 0.95rem;
  }
  
  @media (max-width: 768px) {
  
    .site-footer {
      margin-top: 56px;
      padding: 56px 8% 28px;
    }
  
    .footer-content {
      flex-direction: column;
      gap: 42px;
    }
  
    .footer-brand,
    .footer-links {
      max-width: 100%;
      min-width: 100%;
  
      margin-left: 0;
    }
  
    .footer-bottom {
      margin-top: 42px;
    }
  
  }
  
  .related-tool {
    max-width: 700px;
    margin: 40px auto 40px;
    padding: 40px;
    border-radius: 28px;
    background:
    radial-gradient(circle at top left, rgba(69, 30, 161, 0.112), transparent 42%),
    rgba(255,255,255,0.045);
    border: 1px solid rgba(255,255,255,0.09);
    text-align: center;
  }
  
  .related-tool p {
    margin-bottom: 18px;
    color: rgba(255,255,255,0.6);
    font-size: 1rem;
    font-weight: 600;
  }
  
  .related-tool a {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
  
    padding: 22px 26px;
    border-radius: 22px;
  
    background: rgba(255,255,255,0.045);
    border: 1px solid rgba(139,92,246,0.28);
  
    color: white;
    text-decoration: none;
    transition: 0.2s ease;
  }
  
  .related-preview {
    font-size: 1.8rem;
    line-height: 1.1;
    font-weight: 700;
  }
  
  .related-title {
    color: #a78bfa;
    font-weight: 800;
  }
  
  .related-tool a:hover {
    transform: translateY(-2px);
    background: rgba(255,255,255,0.065);
    border-color: rgba(139,92,246,0.55);
  }
  @media (max-width: 768px) {
    .related-tool {
      width: 84%;
      max-width: 700px;
      margin: 56px auto 40px;
      padding: 26px 20px;
    }
  
    .related-tool a {
      width: 100%;
    }

    .related-preview {
      font-size: 1.1rem;
      line-height: 1.1;
      font-weight: 700;
    }
  }