:root {
    --primary-color: #3498db;
    --secondary-color: #2c3e50;
    --accent-yes: #27ae60;
    --accent-maybe: #f39c12;
    --accent-visited: #95a5a6;
    --bg-color: #f4f6f7;
    --card-bg: #ffffff;
    --text-color: #333;
    --text-muted: #5f6f73;
    --border-color: #ddd;
    --header-height: 60px;
    --nav-height: 50px;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    height: 100vh;
    height: 100dvh;
    overflow: hidden; /* App-like layout */
}

button {
    cursor: pointer;
    border: none;
    background: none;
    font-family: inherit;
}

a {
    color: var(--primary-color);
    text-decoration: none;
}

.hidden {
    display: none !important;
}

/* Custom Scrollbar for panels */
.custom-scrollbar::-webkit-scrollbar {
    width: 6px;
}
.custom-scrollbar::-webkit-scrollbar-track {
    background: #f1f1f1; 
}
.custom-scrollbar::-webkit-scrollbar-thumb {
    background: #ccc; 
    border-radius: 3px;
}
.custom-scrollbar::-webkit-scrollbar-thumb:hover {
    background: #aaa; 
}

/* Base button styles */
.primary-btn {
    background-color: var(--primary-color);
    color: white;
    padding: 8px 16px;
    border-radius: 4px;
    font-weight: 600;
}
.primary-btn:hover {
    background-color: #2980b9;
}

.primary-btn:disabled,
.primary-btn[aria-disabled="true"] {
    cursor: not-allowed;
    opacity: 0.65;
    background-color: #8aa9bf;
}

.primary-btn:disabled:hover,
.primary-btn[aria-disabled="true"]:hover {
    background-color: #8aa9bf;
}

.secondary-btn {
    background-color: #f1f2f6;
    color: var(--text-color);
    padding: 8px 16px;
    border-radius: 4px;
    font-weight: 600;
    border: 1px solid var(--border-color);
}
.secondary-btn:hover {
    background-color: #e1e2e6;
    border-color: #ccc;
}

.danger-btn {
    background-color: #e74c3c;
    color: white;
    padding: 8px 16px;
    border-radius: 4px;
    font-weight: 600;
}
.danger-btn:hover {
    background-color: #c0392b;
}

.icon-btn {
    min-width: 44px;
    min-height: 44px;
    padding: 8px;
    color: white;
    border-radius: 50%;
}
.icon-btn:hover {
    background-color: rgba(255,255,255,0.1);
}