body::before {
    content: "";
    position: fixed;
    inset: 0;
    background-image: url("../images/logo.png");
    background-repeat: no-repeat;
    background-position: center;
    background-size: 320px auto;
    opacity: 0.08;
    pointer-events: none;
    z-index: 0;
}
#about-section {
    max-width: 600px;
    margin: 2rem auto;
    padding: 1.5rem 2rem;
    background: rgba(255,255,255,0.07);
    border-radius: 10px;
    border: 1px solid #bfff28;
    text-align: center;
    color: #dedede;
}

#footer {
    width: 100%;
    background: #1e293b;
    color: #fff;
    padding: 1.2rem 0 1rem 0;
    margin-top: auto;
}
.footer-content {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1.5rem;
    font-size: 1.05rem;
}

.contact-link {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    color: #ffffff;
    text-decoration: none;
    transition: color 0.2s ease;
}

.social-icon {
    width: 28px;
    height: 28px;
    fill: currentColor;
}

.contact-link:hover {
    color: #bfff28;
}
#navbar {
    width: 100%;
    background: #1e293b;
    padding: 0.5rem 0;
    margin-bottom: 1.5rem;
}
.navbar-content {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 2rem;
    max-width: 900px;
    margin: 0 auto;
}

.tablink {
    background: transparent;
    color: #fff;
    border: none;
    border-radius: 8px;
    padding: 0.45rem 0.85rem;
    font-weight: 600;
    font-size: 1.05rem;
    cursor: pointer;
    transition: color 0.15s, background-color 0.15s;
}

.tablink:hover,
.tablink.active {
    color: #bfff28;
    background: rgba(191, 255, 40, 0.12);
}
#title-section,
#description-section,
#about-section,
#flashcards-section {
    width: 100%;
    max-width: 600px;
    margin: 0 auto 2rem auto;
    display: block;
}

.tabcontent {
    display: none;
}

#tab-pages {
    flex: 1;
}

#title-section {
    margin-top: 2.5rem;
    text-align: center;
}

#title-section h1 {
    margin: 0;
    font-size: 3rem;
    line-height: 1.1;
}

#description-section {
    text-align: center;
    padding: 10px;
    font-size: 1.1rem;
    color: #3b4c72fa;
    background-color: rgb(220, 220, 220);
}

#flashcards-section {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.have-fun-text {
    font-size: 4rem;
    font-weight: 900;
    margin-top: 2rem;
    background: linear-gradient(90deg, #bfff28, #00d4ff, #ff6ef7, #bfff28);
    background-size: 300% auto;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: funSlide 1.1s cubic-bezier(0.22, 1, 0.36, 1) both, funGradient 3s linear infinite;
    display: inline-block;
}

@keyframes funSlide {
    from { opacity: 0; transform: scale(4); filter: blur(18px); }
    to   { opacity: 1; transform: scale(1); filter: blur(0);    }
}

@keyframes funGradient {
    0%   { background-position: 0%   center; }
    100% { background-position: 300% center; }
}
body {
    font-family: Arial, sans-serif;
    margin: 0;
    background: #0f172a;
    color: #ffffff;
    min-height: 100vh;
    position: relative;
    display: flex;
    flex-direction: column;
}


#navbar, .navbar-content, section, #card {
    position: relative;
    z-index: 1;
}
#card {
    background: #ffffff;
    padding: 30px;
    width: 60%;
    max-width: 600px;
    margin: 0 auto;
    border-radius: 12px;
    border: 4px solid rgb(176, 255, 40);
    box-shadow: 0 10px 30px rgba(0,0,0,0.3);
    text-align: center;
}

#question {
    font-size: 1.2rem;
    margin-bottom: 15px;
    color: #0f172a;
}

#answer {
    display: none;
    margin-top: 10px;
    font-size: 1rem;
    color: #0f172a;
}

#topic {
    font-size: 0.85rem;
    color: #6b7280;
    margin-bottom: 10px;
}

.buttons {
    margin-top: 20px;
    display: flex;
    justify-content: center;
    gap: 10px;
}

button {
    padding: 10px 18px;
    font-size: 0.95rem;
    border-radius: 6px;
    border: none;
    cursor: pointer;
    font-weight: 600;
}

#showBtn {
    background: #2563eb;
    color: #ffffff;
}

#nextBtn {
    background: #e5e7eb;
    color: #111827;
}

#progress {
    margin-top: 12px;
    font-size: 0.85rem;
    color: #6b7280;
}