<div class="page">
  <div class="logo"><span>DB</span> Consulting</div>
  <div class="home">
    <div class="welcome">
      <h1>DB Consulting</h1>
      <p>Aidez-nous à vous aider</p>
      <p>
        <a href="#services" class="btn btn-light">Nos services</a>
        <a href="#contacts" class="btn btn-light">Contactez-nous</a>
      </p>
    </div>
  </div>
  <div class="services" id="services">
    <h2>Nos services</h2>
    <div>
      <div class="service-block">
        <div class="service-img"></div>
        <h3>Adipiscing elit</h3>
        <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Proin mollis dapibus nulla ac consectetur. Etiam vehicula, ante vel interdum accumsan, elit odio gravida tortor, eu faucibus dolor lacus sed eros. </p>
      </div>
      <div class="service-block">
        <div class="service-img"></div>
        <h3>Fusce et sodales lectus</h3>
        <p>Fusce et dictum sodales lectus, vitae congue odio. Ut pharetra, nibh dictum euismod euismod, est ante tempor justo, non elementum nunc elit vel eros. Sed fringilla, lectus molestie mollis gravida.</p>
      </div>
      <div class="service-block">
        <div class="service-img"></div>
        <h3>Quisque venenatis</h3>
        <p>libero lacus tempus est, a congue quam est eget lorem. Vivamus ultricies eros ligula, eget placerat est fermentum porta. Cras in facilisis lectus. Aliquam ultricies risus non tortor.</p>
      </div>
    </div>
  </div>
  <div class="contacts" id="contacts">
    <h2>Contactez-nous</h2>

    <form method="get">
      <label for="nom">Votre nom et votre prénom</label>
      <input type="text" name="nom" id="nom">

      <label for="telephone">Votre téléphone</label>
      <input type="text" name="telephone" id="telephone">

      <label for="sujet">Sujet de votre message</label>
      <input type="text" name="sujet" id="sujet">

      <label for="message">Sujet de votre message</label>
      <textarea name="message" id="message"></textarea>

      <input class="btn" type="submit" name="submit" value="Envoyer">
    </form>

  </div>
  <footer>
    &copy; 2018 Oueb De Veloper | Tous droits réservés
  </footer>
</div>
$txt-default: #333;
$color1: #00c1db;
$color2: #008da0;

@mixin gradient-radial($color1, $color2) {
  background: $color1;
  background: -moz-radial-gradient(
    center,
    ellipse cover,
    $color1 0%,
    $color2 100%
  );
  background: -webkit-radial-gradient(
    center,
    ellipse cover,
    $color1 0%,
    $color2 100%
  );
  background: radial-gradient(ellipse at center, $color1 0%, $color2 100%);
  filter: progid:DXImageTransform.Microsoft.gradient(
      startColorstr="#{$color1}",
      endColorstr="#{$color2}",
      GradientType=1
    );
}

@import url("https://fonts.googleapis.com/css?family=Raleway:400,700");

html,
body {
  padding: 0px;
  margin: 0px;
  font-family: "Raleway", sans-serif;
  color: $txt-default;
  font-size: 16px;
}

.logo {
  position: absolute;
  font-size: 1.6rem;
  line-height: 3rem;
  padding: 10px 4rem;

  span {
    position: fixed;
    display: inline-block;
    top: 10px;
    left: 10px;
    color: $color2;
    background-color: #fff;
    width: 3rem;
    height: 3rem;
    text-align: center;
    border-radius: 50%;
    border: 1px solid $color2;
  }
}

.btn {
  border: 1px solid #fff;
  color: #fff;
  padding: 0.5rem 1rem;
  margin: 0 0.3rem;
  border-radius: 0.2rem;
  text-decoration: none;
}

.home {
  min-height: 500px;
  height: 100vh;
  padding: 4rem 4rem;
  box-sizing: border-box;
  @include gradient-radial($color1, $color2);
  display: flex;
  flex-direction: column;

  .welcome {
    margin: auto;
    width: 100%;
    text-align: center;
    color: #fff;

    h1 {
      border-bottom: 2px dotted #fff;
      margin: 0 0 2rem 0;
      padding: 0 0 2rem 0;
      font-size: 3rem;
    }
  }
}

.services {
  padding: 4rem 4rem;

  h2 {
    color: $color2;
  }

  & > div {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
  }

  .service-block {
    width: 30%;
    min-width: 280px;
    margin: 1.5%;
    box-sizing: border-box;

    h3 {
      color: $color2;
      text-align: center;
    }

    .service-img {
      background-color: #ccc;
      height: 150px;
    }
  }
}

.contacts {
  padding: 4rem 4rem;
  background-color: #ddd;

  form {
    display: flex;
    flex-wrap: wrap;
    flex-direction: column;

    label {
      margin: 1rem 0;
    }
    input,
    textarea {
      border: 1px solid $color2;
      padding: 10px;
      border-radius: 5px;
    }
    textarea {
      height: 15rem;
    }
    input:focus,
    textarea:focus {
      border: 1px solid #fff;
      padding: 10px;
      border-radius: 5px;
      background-color: lighten($color2, 5%);
      color: #fff;
    }
    input[type="submit"] {
      background-color: $color2;
      width: 25%;
      margin: 1rem auto;
    }
  }
}

footer {
  padding: 1rem 4rem;
  background-color: darken($color2, 15%);
  color: $color2;
  text-align: center;
  font-size: 0.8rem;
}
View Compiled
$(document).ready(function() {
  $('a[href^="#"]').click(function() {
    var id = $(this).attr("href");
    if (id === "#") {
      return ;
    }
    $("html, body").animate(
      {
        scrollTop: $(id).offset().top
      },
      "slow"
    );
  });
});

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

  1. https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js