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

html {
    font-size: 100%;
}
/* } 16px */

:root {
    /* colors */
    --primary-100: #e2e0ff;
    --primary-200: #c1beff;
    --primary-300: #a29dff;
    --primary-400: #837dff;
    --primary-500: #645cff;
    --primary-600: #504acc;
    --primary-700: #3c3799;
    --primary-800: #282566;
    --primary-900: #141233;

    /* grey */
    --grey-50: #f8fafc;
    --grey-100: #f1f5f9;
    --grey-200: #e2e8f0;
    --grey-300: #cbd5e1;
    --grey-400: #94a3b8;
    --grey-500: #64748b;
    --grey-600: #475569;
    --grey-700: #334155;
    --grey-800: #1e293b;
    --grey-900: #0f172a;
    /* rest of the colors */
    --black: #222;
    --white: #fff;
    --red-light: #f8d7da;
    --red-dark: #842029;
    --green-light: #d1e7dd;
    --green-dark: #0f5132;

    /* fonts */
    --small-text: 0.875rem;
    --extra-small-text: 0.7em;
    /* rest of the vars */
    --backgroundColor: var(--grey-50);
    --textColor: var(--grey-900);
    --borderRadius: 0.25rem;
    --letterSpacing: 1px;
    --transition: 0.3s ease-in-out all;
    --max-width: 1120px;
    --fixed-width: 600px;

    /* box shadow*/
    --shadow-1: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
    --shadow-2: 0 4px 6px -1px rgba(0, 0, 0, 0.1),
    0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-3: 0 10px 15px -3px rgba(0, 0, 0, 0.1),
    0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-4: 0 20px 25px -5px rgba(0, 0, 0, 0.1),
    0 10px 10px -5px rgba(0, 0, 0, 0.04);
}
body {
    background: var(--backgroundColor);
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen,
      Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    font-weight: 400;
    line-height: 1.75;
    color: var(--textColor);
  }
  
  p {
    margin-bottom: 1.5rem;
    max-width: 40em;
  }
  
  h1,
  h2,
  h3,
  h4,
  h5 {
    margin: 0;
    margin-bottom: 1.38rem;
    font-weight: 400;
    line-height: 1.3;
    text-transform: capitalize;
    letter-spacing: var(--letterSpacing);
  }
  
  h1 {
    margin-top: 0;
    font-size: 3.052rem;
  }
  
  h2 {
    font-size: 2.441rem;
  }
  
  h3 {
    font-size: 1.953rem;
  }
  
  h4 {
    font-size: 1.563rem;
  }
  
  h5 {
    font-size: 1.25rem;
  }
  
  small,
  .text-small {
    font-size: var(--small-text);
  }
  
  a {
    text-decoration: none;
  }
  ul {
    list-style-type: none;
    padding: 0;
  }
  
  .img {
    width: 100%;
    display: block;
    object-fit: cover;
  }
  /* buttons */
  
  .btn {
    cursor: pointer;
    color: var(--white);
    background: var(--primary-500);
    border: transparent;
    border-radius: var(--borderRadius);
    letter-spacing: var(--letterSpacing);
    padding: 0.375rem 0.75rem;
    box-shadow: var(--shadow-1);
    transition: var(--transition);
    text-transform: capitalize;
    display: inline-block;
  }
  .btn:hover {
    background: var(--primary-700);
    box-shadow: var(--shadow-3);
  }
  
  @keyframes spinner {
    to {
      transform: rotate(360deg);
    }
  }
  
  .loading {
    width: 6rem;
    height: 6rem;
    border: 5px solid var(--grey-400);
    border-radius: 50%;
    border-top-color: var(--primary-500);
    animation: spinner 0.6s linear infinite;
  }
  .loading {
    margin: 0 auto;
    margin-top: 4rem;
  }
  /* title */
  
  .title {
    text-align: center;
    margin-bottom: 3rem;
  }
  
  .title-underline {
    background: var(--primary-500);
    width: 7rem;
    height: 0.25rem;
    margin: 0 auto;
    margin-top: -1rem;
  }
  
  /*
  =============== 
  Wikipedia 
  ===============
  */
  .wiki {
    padding: 5rem 0;
    width: 90vw;
    max-width: 1170px;
    margin: 0 auto;
  }
  .container {
    text-align: center;
  }
  .container img {
    width: 200px;
  }
  .container h3 {
    margin-bottom: 2rem;
  }
  
  .form {
    background: #fff;
    width: 100%;
    margin: 0 auto;
    padding: 2.5rem;
    border-radius: var(--borderRadius);
    display: grid;
    grid-template-columns: auto 100px;
  }
  .form-input,
  .submit-btn {
    padding: 0.375rem 0.75rem;
    background: var(--backgroundColor);
    border: 1px solid var(--grey-200);
  }
  .form-input {
    border-right: transparent;
    border-top-left-radius: var(--borderRadius);
    border-bottom-left-radius: var(--borderRadius);
  }
  .submit-btn {
    border: 1px solid var(--primary-500);
    border-left: transparent;
    border-top-right-radius: var(--borderRadius);
    border-bottom-right-radius: var(--borderRadius);
    text-transform: capitalize;
    background: var(--primary-500);
    color: var(--white);
    transition: var(--transition);
    cursor: pointer;
  }
  .submit-btn:hover {
    color: var(--primary-900);
  }
  
  .results {
    padding: 2rem 0;
  }
  
  .error {
    text-align: center;
    text-transform: capitalize;
    color: var(--red-dark);
  }
  
  .articles {
    display: grid;
    gap: 1rem;
  }
  
  .articles a {
    display: block;
    background: var(--white);
    color: var(--textColor);
    padding: 1.5rem 2rem;
    border-radius: var(--borderRadius);
    transition: var(--transition);
  }
  .articles p {
    color: var(--grey-500);
    transition: var(--transition);
  }
  
  .articles a:hover {
    background: var(--black);
    color: var(--white);
  }
  
  @media screen and (min-width: 768px) {
    .articles {
      grid-template-columns: 1fr 1fr;
    }
    .form {
      max-width: 600px;
    }
  }
  @media screen and (min-width: 992px) {
    .articles {
      grid-template-columns: 1fr 1fr 1fr;
    }
  }