:root {
    --background-color: #FFFFFC;
    --text-color: #444444;
    --secondary-text-color: #647F98;
    --accent-color: #79915C;
    --border-color: #E2E1DF;
    --body-font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    --content-width: 700px;
    --base-font-size: 17px;
    --base-line-height: 1.6;
}
html[data-theme='paper'] {
    --background-color: #FFFFFC;
    --text-color: #444444;
    --secondary-text-color: #647F98;
    --accent-color: #79915C;
    --border-color: #E2E1DF;
}
html[data-theme='charcoal'] {
    --background-color: #232322;
    --text-color: #F8F7F6;
    --secondary-text-color: #B6C9DB;
    --accent-color: #DCC48E;
    --border-color: #3A3A37;
}
html[data-theme='sepia'] {
    --background-color: #F4F0E8;
    --text-color: #4A4033;
    --secondary-text-color: #7A6A58;
    --accent-color: #B35900;
    --border-color: #DCD3C3;
}
html[data-theme='slate'] {
    --background-color: #2E3440;
    --text-color: #ECEFF4;
    --secondary-text-color: #D8DEE9;
    --accent-color: #88C0D0;
    --border-color: #4C566A;
}
html[data-theme='monochrome'] {
    --background-color: #FFFFFC;
    --text-color: #222222;
    --secondary-text-color: #555555;
    --accent-color: #444444;
    --border-color: #DDDDDD;
}
html[data-font='serif'] { --body-font: Georgia, Merriweather, "Source Serif Pro", serif; }
html[data-font='mono'] { --body-font: ui-monospace, SFMono-Regular, SF Mono, Menlo, Consolas, "Liberation Mono", monospace; }

body { 
    font-family: var(--body-font); 
    background-color: var(--background-color); 
    color: var(--text-color); 
    margin: 0; 
    padding: 2rem 1rem; 
    font-size: var(--base-font-size); 
    line-height: var(--base-line-height); 
    transition: background-color 0.3s, color 0.3s, border-color 0.3s; 
}
.site-header { 
    max-width: var(--content-width); 
    margin: 0 auto; 
    padding-bottom: 2rem; 
    border-bottom: 1px solid var(--border-color); 
    margin-bottom: 2rem; 
    position: relative; 
}
.header-main {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.5rem;
}
h1 { font-size: 2.5rem; margin: 0; font-weight: normal; line-height: 1.2; }
.site-header p { font-size: 1.2rem; color: var(--secondary-text-color); margin-top: 0.5rem; margin-bottom: 1rem; }

/* Theme Toggle Button */
.theme-toggle {
    background: transparent;
    border: none;
    cursor: pointer;
    width: 44px;
    height: 44px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-color);
    transition: background-color 0.2s, color 0.2s;
    padding: 0;
    margin: 0;
}
.theme-toggle:hover {
    background-color: var(--border-color);
}
.theme-toggle svg {
    width: 24px;
    height: 24px;
}

#feed-container { max-width: var(--content-width); margin: 0 auto; }
.site-nav { display: flex; justify-content: flex-start; align-items: center; }
.nav-toggle { display: none; background: none; border: none; cursor: pointer; padding: 0; color: var(--text-color); z-index: 1001; }
.nav-links { list-style: none; margin: 0; padding: 0; display: flex; gap: 1.5rem; }
.nav-links a { text-decoration: none; color: var(--secondary-text-color); font-weight: 500; font-size: 0.95rem; }
.nav-links a:hover { color: var(--accent-color); }
@media (max-width: 768px) {
    .site-nav { justify-content: flex-end; }
    .nav-toggle { display: block; position: absolute; top: calc(2rem - 8px); right: 1rem; }
    .nav-links { display: none; position: absolute; top: 60px; right: 0; flex-direction: column; background: var(--background-color); border: 1px solid var(--border-color); border-radius: 8px; padding: 1rem; box-shadow: 0 4px 12px rgba(0,0,0,0.1); gap: 1rem; z-index: 1000; min-width: 180px; }
    .nav-links.active { display: flex; }
}
.feed-item { padding-bottom: 1.5rem; margin-bottom: 1.5rem; border-bottom: 1px solid var(--border-color); transition: border-color 0.3s; }
.feed-item:last-child { border-bottom: none; margin-bottom: 0; }
.item-meta { font-size: 0.9rem; color: var(--secondary-text-color); font-weight: 500; margin-bottom: 0.25rem; display: flex; flex-wrap: wrap; gap: 0.25rem 0.5rem; }
.item-meta .separator { color: var(--border-color); }
.item-title { font-size: 1.5rem; margin: 0 0 0.5rem 0; font-weight: normal; }
.item-title a { color: var(--text-color); text-decoration: none; }
.item-title a:hover { color: var(--accent-color); text-decoration: underline; }
.item-summary { margin: 0.5rem 0 1rem 0; }
.item-actions { display: flex; gap: 0.75rem; margin: 1rem 0; }
.action-button { background-color: transparent; border: 1px solid var(--border-color); color: var(--secondary-text-color); padding: 0.4rem 0.8rem; font-size: 0.85rem; font-weight: 500; border-radius: 20px; text-decoration: none; cursor: pointer; transition: background-color 0.2s, color 0.2s, border-color 0.2s; }
.action-button:hover { background-color: var(--border-color); color: var(--text-color); }
.item-audio { width: 100%; margin-top: 1rem; }
a { color: var(--accent-color); }
.error-message { color: var(--secondary-text-color); }
.loading-message { display: flex; align-items: center; justify-content: center; gap: 0.75rem; font-size: 1.1rem; color: var(--secondary-text-color); padding: 2rem; }
@keyframes spin { to { transform: rotate(360deg); } }
.spinner { width: 20px; height: 20px; border: 3px solid var(--border-color); border-top-color: var(--secondary-text-color); border-radius: 50%; animation: spin 1s linear infinite; }