:root {
    --primary-color: #4A90E2;
    --secondary-color: #333333;
    --text-light: #666666;
    --background-light: #f4f4f4;
    --card-background: #fff;
    --border-color: #e0e0e0;
    --shadow-light: rgba(0, 0, 0, 0.08);
    --shadow-medium: rgba(0, 0, 0, 0.12);
    --spacing-small: 10px;
    --spacing-medium: 15px;
    --spacing-large: 20px;
    --spacing-xl: 30px;
}

body, html {
    margin: 0;
    padding: 0;
    width: 100%;
    height: 100%;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji";
    background-color: var(--background-light);
    color: var(--secondary-color);
}

.site-header {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 100;
    background-color: var(--card-background);
    border-bottom: 1px solid var(--border-color);
    box-shadow: 0 2px 8px var(--shadow-light);
}
.header-container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 0;
}
.site-title {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--primary-color);
    text-decoration: none;
    letter-spacing: -0.5px;
}
.main-nav {
    display: flex;
    align-items: center;
}

.main-nav .nav-link {
    color: var(--text-light);
    text-decoration: none;
    margin-left: var(--spacing-large);
    font-size: 1rem;
    padding: 5px var(--spacing-small);
    position: relative;
    transition: color 0.2s, transform 0.2s, background-color 0.2s;
    border-radius: 4px;
}
.main-nav .nav-link:hover {
    color: var(--primary-color);
    transform: translateY(-2px);
    background-color: rgba(74, 144, 226, 0.1);
}
.main-nav .nav-link::after {
    content: '';
    position: absolute;
    width: 0%;
    height: 2px;
    bottom: 0;
    left: 0;
    background-color: var(--primary-color);
    transition: width 0.3s ease-in-out;
}
.main-nav .nav-link:hover::after {
    width: 100%;
}

.hamburger-menu {
    display: none; /* Hidden on desktop */
    cursor: pointer;
    padding: 10px;
    z-index: 101; /* Ensure it's above other content */
}

.hamburger-menu .bar {
    width: 25px;
    height: 3px;
    background-color: var(--primary-color);
    margin: 5px 0;
    transition: 0.4s;
}

.hamburger-menu.active .bar:nth-child(1) {
    transform: translateY(8px) rotate(45deg);
}

.hamburger-menu.active .bar:nth-child(2) {
    opacity: 0;
}

.hamburger-menu.active .bar:nth-child(3) {
    transform: translateY(-8px) rotate(-45deg);
}

.site-footer-main {
    padding: var(--spacing-xl) 0;
    background-color: var(--card-background);
    border-top: 1px solid var(--border-color);
    text-align: center;
    font-size: 0.9rem;
    color: var(--text-light);
    box-shadow: 0 -2px 8px var(--shadow-light);
}
.footer-container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
}
.footer-container p {
    margin: 0;
}
.footer-container a {
    color: var(--text-light);
    text-decoration: none;
    margin: 0 5px;
}
.footer-container a:hover {
    color: var(--primary-color);
    text-decoration: underline;
}

@media (max-width: 768px) {
    .hamburger-menu {
        display: block; /* Show on mobile */
    }

    .main-nav {
        display: none; /* Hidden by default on mobile */
        flex-direction: column;
        width: 100%;
        position: absolute;
        top: 100%; /* Make it start right below the header */
        left: 0;
        background-color: var(--card-background);
        box-shadow: 0 8px 16px var(--shadow-medium);
        border-top: 1px solid var(--border-color);
        padding-bottom: 10px;
    }

    .main-nav.active {
        display: flex; /* Show when active */
    }

    .main-nav .nav-link {
        margin: 0; /* Reset margin for vertical layout */
        padding: 15px 20px;
        border-bottom: 1px solid var(--border-color);
    }

    .main-nav .nav-link:last-child {
        border-bottom: none;
    }

    .main-nav .search-form {
        width: 90%;
        max-width: 300px; /* Reduced max-width */
        margin: 15px auto;
    }

    body.menu-open {
        overflow: hidden; /* Prevent scrolling when menu is open */
    }
    .site-header {
        position: relative;
    }
    .header-container {
        padding: 15px 0;
    }
    .page-container {
        padding-top: 20px;
        margin-top: 0; /* Set to 0 to remove any top margin */
    }
    .sentence-detail-container {
        padding: 20px;
        min-height: auto;
    }
    .sentence-content {
        font-size: 2rem;
    }
    .button-container {
        position: static;
        margin-top: 40px;
    }
    .site-footer-main {
        margin-top: 40px;
    }
}

.sentence-detail-container {
    width: 100%;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 100px 20px 100px;
    box-sizing: border-box;
}

.sentence-card {
    max-width: 800px;
    text-align: center;
    background-color: var(--card-background);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: var(--spacing-xl);
    box-shadow: 0 4px 12px var(--shadow-light);
    transition: transform 0.2s ease-in-out, box-shadow 0.2s ease-in-out;
}

.sentence-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 6px 16px var(--shadow-medium);
}

.sentence-content {
    font-family: "Palatino Linotype", "Book Antiqua", Palatino, serif;
    font-size: 2.2rem;
    font-weight: 400;
    line-height: 1.5;
    margin-bottom: 2rem;
    color: var(--secondary-color);
}

.sentence-author {
    font-size: 1.2rem;
    font-style: italic;
    color: #777;
}

.button-container {
    position: absolute;
    bottom: 40px;
    display: flex;
    gap: 15px;
}

.base-card {
    background-color: var(--card-background);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: var(--spacing-xl);
    box-shadow: 0 4px 12px var(--shadow-light);
    transition: transform 0.2s ease-in-out, box-shadow 0.2s ease-in-out;
}

.base-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 6px 16px var(--shadow-medium);
}

.action-button {
    padding: 12px 25px;
    border: 1px solid #ccc;
    border-radius: 50px;
    background-color: #fff;
    color: #333;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s;
    text-decoration: none;
}
.action-button:hover {
    background-color: var(--primary-color);
    color: #fff;
    border-color: var(--primary-color);
    transform: translateY(-2px);
    box-shadow: 0 4px 8px var(--shadow-light);
}

.search-container {
    display: flex;
    justify-content: center;
    margin: var(--spacing-xl) auto;
    max-width: 600px;
}

.search-input {
    flex-grow: 1;
    padding: 12px 20px;
    border: 1px solid var(--border-color);
    border-radius: 50px 0 0 50px;
    font-size: 1rem;
    color: var(--secondary-color);
    outline: none;
    transition: border-color 0.3s, box-shadow 0.3s;
}

.search-input:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(74, 144, 226, 0.2);
}

.search-button {
    padding: 12px 25px;
    border: 1px solid var(--primary-color);
    border-left: none;
    border-radius: 0 50px 50px 0;
    background-color: var(--primary-color);
    color: #fff;
    font-size: 1rem;
    cursor: pointer;
    transition: background-color 0.3s, border-color 0.3s, transform 0.2s;
    outline: none;
}

.search-button:hover {
    background-color: #357ABD;
    border-color: #357ABD;
    transform: translateY(-1px);
}

.error-message {
    font-size: 1.5rem;
    color: #e74c3c;
}

.page-container {
    width: 90%;
    max-width: 1200px;
    margin: 20px auto;
    padding-top: 40px;
}
.page-title {
    font-size: 2.5rem;
    margin-bottom: 30px;
    text-align: center;
    color: var(--secondary-color);
}
.sentence-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 25px;
}
.sentence-card-grid {
    background-color: var(--card-background);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: var(--spacing-xl);
    box-shadow: 0 4px 12px var(--shadow-light);
    transition: transform 0.2s ease-in-out, box-shadow 0.2s ease-in-out;
    text-decoration: none;
    color: var(--secondary-color);
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.sentence-card-grid:hover {
    transform: translateY(-5px);
    box-shadow: 0 6px 16px var(--shadow-medium);
}
.card-content {
    font-size: 1.2rem;
    line-height: 1.6;
    flex-grow: 1;
    color: var(--secondary-color);
}
.card-author {
    font-size: 0.9rem;
    color: var(--text-light);
    margin-top: 20px;
    text-align: right;
}

.top-sentences-list {
    list-style: decimal;
    padding-left: 25px;
}

.top-sentences-list li {
    margin-bottom: var(--spacing-medium);
}

.top-sentence-item {
    display: block;
    text-decoration: none;
    color: var(--secondary-color);
    padding: var(--spacing-medium) var(--spacing-large);
    background-color: var(--card-background);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    box-shadow: 0 4px 12px var(--shadow-light);
    transition: transform 0.2s ease-in-out, box-shadow 0.2s ease-in-out;
}

.top-sentence-item:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 16px var(--shadow-medium);
}

.top-sentence-content {
    font-size: 1.1em;
    line-height: 1.6;
    margin-bottom: var(--spacing-small);
}

.top-sentence-meta {
    font-size: 0.85em;
    color: var(--text-light);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.top-sentence-likes {
    font-weight: 700;
    color: var(--primary-color);
}