* {
    box-sizing: border-box;
  }
  
  html, body {
    margin: 0;
    padding: 0;
    width: 100%;
    min-height: 100%;
    font-family: "Poppins", sans-serif;
    background-color: #EEF0EB;
  }
  
  /* ===== HERO SECTION ===== */
  #hero-main {
    background-color: #111111;
    display: grid;
    place-items: center;
    padding: 40px 20px;
    text-align: center;
  }
  
  #logo {
    max-width: 100%;
    height: auto;
    max-height: 300px;
  }
  
  #hero-h1 {
    font-size: 2rem;
    color: #F4F9E9;
    letter-spacing: 2px;
    margin-top: 20px;
  }

  #how-main {
    background-color: #F4F9E9;
    padding: 60px 20px;
    text-align: center;
  }
  
  #how-h1 {
    font-size: 2rem;
    color: #153243;
    margin-bottom: 20px;
  }
  
  #how-p1,
  #how-p2 {
    font-size: 1.1rem;
    color: #153243;
    margin: 15px auto;
    max-width: 600px;
    line-height: 1.6;
  }
  
  #how-link {
    display: inline-block;
    margin: 20px auto;
    font-size: 1rem;
    color: #284B63;
    text-decoration: none;
    font-weight: 500;
    border: 2px solid #284B63;
    padding: 10px 20px;
    border-radius: 8px;
    transition: background-color 0.3s, color 0.3s;
  }
  
  #how-link:hover {
    background-color: #284B63;
    color: #ffffff;
  }
  
  /* ===== UPLOAD SECTION ===== */
  #upload-main {
    background-color: #B4B8AB;
    padding: 60px 20px;
    text-align: center;
  }
  
  #upload-h1 {
    font-size: 2rem;
    color: #111111;
    margin-bottom: 30px;
  }
  
  .upload-flex {
    display: flex;
    flex-direction: column;
    align-items: center;
  }
  
  #drop-area {
    border: 2px dashed #ccc;
    border-radius: 12px;
    width: 100%;
    max-width: 350px;
    height: 150px;
    padding: 20px;
    background-color: #fff;
    transition: border 0.3s;
  }
  
  #drop-area.highlight {
    border-color: purple;
  }
  
  #fileSelect {
    margin-top: 10px;
    padding: 10px 20px;
    cursor: pointer;
    font-size: 1rem;
  }
  
  #file-list {
    list-style: none;
    margin-top: 20px;
    padding: 0;
  }
  
  /* ===== CHART SECTION ===== */
  #charts-main {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 40px;
    padding: 40px 20px;
    background-color: #EEF0EB;
  }
  
  
  #charts-main canvas {
    flex: 1 1 400px;
    max-width: 600px;
    width: 100%;
    aspect-ratio: 2 / 1;
    background-color: #fff;
    border: 1px solid #ccc;
    border-radius: 12px;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.1);
  }
  
  /* ===== EXAMPLES SECTION ===== */
  #examples-main {
    background-color: #111111;
    padding: 60px 20px;
    text-align: center;
  }
  
  #examples-h1 {
    font-size: 2rem;
    color: #B4B8AB;
    margin-bottom: 40px;
  }
  
  .flex-examples {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 20px;
  }
  
  .flex-examples img {
    width: 100%;
    max-width: 500px;
    height: auto;
    border-radius: 8px;
  }
  
  /* ===== ABOUT SECTION ===== */
  #about-main {
    background-color: #F4F9E9;
    padding: 60px 20px;
    text-align: center;
  }
  
  #about-h1 {
    font-size: 2rem;
    color: #153243;
    margin-bottom: 20px;
  }
  
  #about-p {
    font-size: 1.2rem;
    color: #153243;
    max-width: 600px;
    margin: 0 auto;
    line-height: 1.5;
  }
  
  /* ===== CONTACT SECTION ===== */
  #contact-main {
    background-color: #EEF0EB;
    padding: 60px 20px;
    text-align: center;
  }
  
  #contact-h1 {
    font-size: 2rem;
    color: #153243;
    margin-bottom: 20px;
  }
  
  .contact-flex > * {
    font-size: 1.1rem;
    color: #153243;
    margin: 5px 0;
  }
  
  /* ===== RESPONSIVE BREAKPOINTS ===== */
  @media (min-width: 600px) {
    #hero-h1, #upload-h1, #examples-h1, #about-h1, #contact-h1 {
      font-size: 2.5rem;
    }
  
    #about-p, .contact-flex > * {
      font-size: 1.3rem;
    }
  
    #drop-area {
      height: 180px;
    }
  }
  
  @media (min-width: 1000px) {
    .flex-examples {
      flex-direction: row;
    }
  
    #examples-h1 {
      font-size: 3rem;
    }
  
    #charts-main {
      flex-direction: row;
      flex-wrap: wrap;
      justify-content: center;
    }
  
    #charts-main canvas {
      width: 45vw;
      max-width: 600px;
    }
  }