body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #1a1a1a;
    color: #fff;
}

header {
    display: flex;
    justify-content: space-between;
    padding: 10px 20px;
    background-color: #2c2c2c;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

#banner {
    background-size: cover;
    background-position: center;
    padding: 20px;
    text-align: center;
    position: relative;
    backdrop-filter: blur(5px);
    min-height: 300px;
}

#cover {
    width: 200px;
    height: 300px;
    border-radius: 10px;
}

.button-group {
    display: flex;
    justify-content: center;
    gap: 10px;
    flex-wrap: wrap;
}

button {
    padding: 10px 20px;
    margin: 5px;
    border: none;
    border-radius: 5px;
    background-color: rgba(0, 0, 0, 0.3);
    color: white;
    cursor: pointer;
    backdrop-filter: blur(5px);
    position: relative;
    transition: background-color 0.3s, transform 0.1s, box-shadow 0.3s, text-shadow 0.3s;
}

#read-from-beginning {
    box-shadow: 0 0 8px rgba(0, 255, 0, 0.5);
    background-color: rgba(0, 255, 0, 0.2);
    text-shadow: 0 0 5px rgba(0, 255, 0, 0.6);
}

#read-from-beginning:hover {
    transform: translateY(-2px);
    background-color: rgba(0, 255, 0, 0.4);
    box-shadow: 0 0 12px rgba(0, 255, 0, 0.8);
    text-shadow: 0 0 10px rgba(0, 255, 0, 0.9);
}

#continue-reading {
    box-shadow: 0 0 8px rgba(255, 165, 0, 0.5);
    background-color: rgba(255, 165, 0, 0.2);
    text-shadow: 0 0 5px rgba(255, 165, 0, 0.6);
}

#continue-reading:hover {
    transform: translateY(-2px);
    background-color: rgba(255, 165, 0, 0.4);
    box-shadow: 0 0 12px rgba(255, 165, 0, 0.8);
    text-shadow: 0 0 10px rgba(255, 165, 0, 0.9);
}

#prev-chapter, #next-chapter, #back-to-main {
    box-shadow: 0 0 5px rgba(30, 144, 255, 0.5);
    background-color: rgba(30, 144, 255, 0.2);
    width: 40px;
    height: 40px;
    padding: 0;
    display: flex;
    align-items: center;
    justify-content: center;
}

#prev-chapter:hover, #next-chapter:hover, #back-to-main:hover {
    transform: translateY(-2px);
    background-color: rgba(30, 144, 255, 0.4);
    box-shadow: 0 0 8px rgba(30, 255, 255, 0.8);
}

#prev-chapter img, #next-chapter img, #back-to-main img {
    width: 24px;
    height: 24px;
    object-fit: contain;
}

.chapter-nav {
    display: flex;
    justify-content: center;
    gap: 10px;
    position: fixed;
    bottom: 20px;
    left: 0;
    right: 0;
    background-color: transparent;
    padding: 10px;
    transition: opacity 0.3s ease;
    flex-wrap: wrap;
    z-index: 10;
}

.chapter-nav.hidden {
    opacity: 0;
    pointer-events: none;
}

#chapter-content {
    white-space: pre-wrap;
    line-height: 1.6;
    margin: 20px;
    padding: 10px;
    background-color: #2c2c2c;
    border-radius: 5px;
}

#chapter-list {
    list-style: decimal;
    padding: 10px 20px;
    max-height: 300px;
    overflow-y: auto;
    background-color: #2c2c2c;
    border-radius: 5px;
    margin: 20px;
}

#chapter-list li {
    padding: 10px;
    margin: 5px 0;
    background-color: #333;
    border-radius: 3px;
    cursor: pointer;
    transition: background-color 0.3s;
}

#chapter-list li:hover {
    background-color: #444;
}

#chapter-list li.read {
    opacity: 0.5;
}

/* Tùy chỉnh thanh cuộn hiện đại */
#chapter-list::-webkit-scrollbar {
    width: 8px;
}

#chapter-list::-webkit-scrollbar-track {
    background: #2c2c2c;
    border-radius: 5px;
}

#chapter-list::-webkit-scrollbar-thumb {
    background: #444;
    border-radius: 5px;
}

#chapter-list::-webkit-scrollbar-thumb:hover {
    background: #555;
}

#introduction {
    margin: 20px;
    padding: 10px;
    background-color: #2c2c2c;
    border-radius: 5px;
}

.centered-title {
    text-align: center;
    margin: 20px 0;
    font-size: 2em;
    color: #1e90ff;
}

#loading-screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.8);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 9999;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 5px solid #f3f3f3;
    border-top: 5px solid #3498db;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* Responsive design */
@media (max-width: 600px) {
    #banner {
        padding: 10px;
        min-height: 200px;
    }

    #cover {
        width: 150px;
        height: 225px;
    }

    #title {
        font-size: 1.5em;
    }

    #genre, #introduction {
        font-size: 0.9em;
    }

    button {
        padding: 8px 16px;
        font-size: 0.9em;
    }

    #prev-chapter, #next-chapter, #back-to-main {
        width: 36px;
        height: 36px;
    }

    #prev-chapter img, #next-chapter img, #back-to-main img {
        width: 20px;
        height: 20px;
    }

    #chapter-list {
        max-height: 200px;
        margin: 10px;
        padding: 10px;
    }

    #chapter-content {
        margin: 10px;
        font-size: 0.9em;
    }

    .chapter-nav {
        gap: 5px;
    }

    .centered-title {
        font-size: 1.5em;
        margin: 10px 0;
    }
}