body {
    margin: 0;
    font-family: 'Roboto', sans-serif;
    color: white;
    background-image: url('back.jpg');
    background-size: cover;
    background-position: center;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    overflow-x: hidden;
    font-weight: 300;
}

header {
    flex-grow: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    padding: 20px;
    backdrop-filter: blur(3px);
    background-color: rgba(0, 0, 0, 0.2);
}

.container {
    max-width: 700px;
    margin: 0 auto;
}

.icon-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    margin-bottom: 20px; 
    animation: fade-in-down 1s ease-out;
}

.diamond-icon {
    font-size: 1.8em;
}
::-moz-selection {
    color: red;
    background: yellow;
  }
  
  ::selection {
    color: red;
    background: yellow;
  }
  

.icon-line {
    width: 700px;
    height: 3px;
    background-color: white;
    margin-top: 5px;
    animation: line-grow 1s ease-out;
}

.line {
    width: 700px;
    height: 3px;
    background-color: white;
    margin: 15px 0;
    animation: line-fade-in 1s ease-out;
}


h1 {
    font-size: 2.2em;
    font-weight: 500;
    margin-bottom: 10px;
    letter-spacing: 1px;
    animation: fade-in 1s ease-out 0.3s;
    animation: text-focus-in 1s cubic-bezier(0.550, 0.085, 0.680, 0.530) both; 
}
.instruction {
    animation: text-pop-up-top 0.8s cubic-bezier(0.460, 0.030, 0.520, 0.960) both;
}
.welcome{
    animation: tracking-in-expand 0.7s cubic-bezier(0.215, 0.610, 0.355, 1.000) both;
}
.welcome, .instruction, .tagline {
    animation: fade-in-up 1s ease-out 0.5s;
}

@keyframes fade-in-up {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}
@keyframes fade-in-down {
    from { opacity: 0; transform: translateY(-20px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes line-fade-in {
    from { opacity: 0; width: 0; }
    to { opacity: 1; width: 700px; }
}
@keyframes line-grow {
    from { opacity: 0; height: 0; }
    to { opacity: 1; height: 30px; }
}

@keyframes diamond-spin {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

@keyframes border-pulse {
    0% { border-color: white; transform: scale(1);}
    50% { border-color: #aaa; transform: scale(1.1);}
    100% { border-color: white; transform: scale(1);}
}
.welcome {
    font-size: 1.1em;
    font-weight: 400;
}

.instruction {
    font-size: 0.9em;
    line-height: 1.4;
    margin-bottom: 20px; 
}

nav {
    display: flex;
    justify-content: center;
    margin-bottom: 20px;
    animation: slide-in-bottom 1s cubic-bezier(0.250, 0.460, 0.450, 0.940) both;
}

nav a {
    color:  white;
    text-decoration: none;
    margin: 0 10px;
    padding: 6px 12px;
    border: 2px solid white;
    border-radius: 3px;

    transition: background-color 0.3s, color 0.3s, transform 0.2s, box-shadow 0.3s; 
    font-size: 0.85em;
    font-weight: 400;
}


nav a:hover {
    background-color: white;
    transform: scale(1.1);
    color: white;
        cursor: pointer;
        background: linear-gradient(180deg, #6A0DAD, #9A4DFF);
             border: 2px  white solid;
                box-shadow: 1px 1px 10px 3px  #6A0DAD;

}

#welcome-screen {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: rgba(255, 255, 255, 0.9);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1); 
    z-index: 999;
    animation: fade-in-out 3s ease-in-out;
  }
  @keyframes fade-in-out {
    0% {
      opacity: 0; 
    }
    25% {
      opacity: 1; 
    }
    75% {
      opacity: 1; 
    }
    100% {
      opacity: 0; 
    }
  }

.tagline {
    font-style: italic;
    font-size: 1.2em;
    font-weight: 300;
    margin-top: 50px; 
    animation: jello-horizontal 0.9s both;
}

.icon-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    margin-bottom: 20px;
}

.diamond-wrapper {
    width: 50px; 
    height: 50px; 
    border-radius: 50%;
    border: 2px solid white; 
    display: flex;
    justify-content: center; 
    align-items: center; 
    animation: border-pulse 2s  ease-in-out;
}

.diamond-icon {
    font-size: 2em; 
    animation: diamond-spin 2s linear ;
}

.icon-line {
    width: 2px;
    height: 30px;
    background-color: white;
    margin-top: 5px;
}
@keyframes fade-in {
    from { opacity: 0; }
    to { opacity: 1; }
}
@keyframes text-focus-in {
    0% {
        filter: blur(12px);
        opacity: 0;
    }
    100% {
        filter: blur(0px);
        opacity: 1;
    }
}

@keyframes tracking-in-expand {
    0% {
        letter-spacing: -0.5em;
        opacity: 0;
    }
    40% {
        opacity: 0.6;
    }
    100% {
        opacity: 1;
    }
}

@keyframes text-pop-up-top {
    0% {
        opacity: 0;
        transform: translateY(-50px);
    }
    100% {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes jello-horizontal {
    0% {
        transform: scale3d(1, 1, 1);
    }
    30% {
        transform: scale3d(1.25, 0.75, 1);
    }
    40% {
        transform: scale3d(0.75, 1.25, 1);
    }
    50% {
        transform: scale3d(1.15, 0.85, 1);
    }
    65% {
        transform: scale3d(0.95, 1.05, 1);
    }
    75% {
        transform: scale3d(1.05, 0.95, 1);
    }
    100% {
        transform: scale3d(1, 1, 1);
    }
}
@keyframes rotate-cw {
    0% {
      transform: rotate(0);
    }
    100% {
      transform: rotate(360deg);
    }
  }
@keyframes slide-in-bottom {
    0% {
      transform: translateY(1000px);
      opacity: 0;
    }
    100% {
      transform: translateY(0);
      opacity: 1;
    }
  }
  @media (max-width: 900px) {
    .container {
        max-width: 90%; 
    }

    .line {
        width: 90%; 
    }
    .icon-line{
        width: 2px;
        height: 20px;
    }
    nav a {
        font-size: 0.75em; 
        padding: 4px 8px; 
        margin: 0 5px;

    }
    h1{
        font-size: 1.8em;
    }
    .welcome{
        font-size: 1em;
    }
    .instruction{
        font-size: 0.8em;
    }
    .diamond-icon{
        font-size: 1.5em;
    }
    .diamond-wrapper{
        width: 40px;
        height: 40px;
    }
}
@media (max-width: 600px) {
    .container {
        max-width: 95%;
    }

    .line {
        width: 95%;
    }

    nav {
        flex-direction: column;
        align-items: center;
    }

    nav a {
        margin: 5px 0;
        width: 100%;
        text-align: center;
        border-radius: 5px;
        font-size: 0.9em;
        padding: 8px;
    }
    .nav-separator{
        display: none;
    }
    h1{
        font-size: 1.5em;
    }
    .welcome{
        font-size: 0.9em;
    }
    .instruction{
        font-size: 0.7em;
    }
    .diamond-icon{
        font-size: 1.2em;
    }
    .diamond-wrapper{
        width: 30px;
        height: 30px;
    }
}


@media (max-width: 768px) {
    body {
      font-size: 16px;
    }

    #welcome-screen {
      padding: 20px;
    }

    #main-content {
      padding: 15px;
    }

    h1 {
      font-size: 28px;
    }

    p {
      font-size: 14px; 
    }
  }

  @media (max-width: 480px) {
    #welcome-screen {
      flex-direction: column; 
      justify-content: center;
      padding: 10px; 
    }

    h1 {
      font-size: 24px; 
    }

    p {
      font-size: 12px; 
    }

    #main-content {
      padding: 10px;
    }
  }