/* CSS Reset & Basic Styles */
* {
    box-sizing: border-box;
}

body {
    font-family: "Microsoft JhengHei", Arial, sans-serif;
    margin: 0;
    padding: 0;
    line-height: 1.6;
    color: #333;
    background-color: #f9f9f9;

    /* Sticky Footer Setup */
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* Accessibility: Skip Link */
.skip-link {
    position: absolute;
    top: -100px;
    left: 0;
    background: #000;
    color: #fff;
    padding: 8px;
    z-index: 5000;
    transition: top 0.3s;
    text-decoration: none;
}

.skip-link:focus {
    top: 0;
}

/* Accessibility: Focus Indication */
a:focus,
button:focus,
input:focus,
select:focus,
textarea:focus {
    outline: 3px solid #005fcc;
    outline-offset: 2px;
}

/* Access Key Marker */
.access-key {
    color: #555;
    text-decoration: none;
    font-size: 0.9em;
    padding: 0 5px;
}

.access-key-container {
    position: relative;
    display: flex;
    align-items: center;
    gap: 10px;
}

.access-key-link {
    font-size: 0.9rem;
    color: #555;
    text-decoration: none;
}

.access-key-link:hover,
.access-key-link:focus {
    text-decoration: underline;
    color: #000;
}

/* Header */
header {
    background-color: #fff;
    border-bottom: 1px solid #ddd;
    padding: 1rem;
}

header h1 {
    margin: 0 0 1rem 0;
    font-size: 1.8rem;
    color: #222;
}

/* Navigation - No Hamburger Menu as requested */
nav ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

nav ul li a {
    text-decoration: none;
    color: #004488;
    font-weight: bold;
    font-size: 1.1rem;
    padding: 5px 10px;
    border: 1px solid transparent;
    /* Prepare for focus state */
}

nav ul li a:hover {
    text-decoration: underline;
    background-color: #f0f0f0;
}

/* Layout Container */
.container {
    display: flex;
    /* Use Flexbox for layout */
    flex-wrap: wrap;
    /* Wrap allowed for mobile */
    width: 100%;
    /* Full width */
    max-width: none;
    /* Remove centering constraint */
    margin: 0;
    /* Remove auto margins */
    padding: 20px;
    gap: 20px;
}

/* Sidebar & Main Content */
/* Sidebar & Main Content Layout Containers */
aside,
main {
    background-color: transparent;
    padding: 0;
    border: none;
    border-radius: 0;
    box-shadow: none;
}

/* Card Component */
.card {
    background-color: #fff;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    border: 1px solid #e0e0e0;
    overflow: hidden;
    margin-bottom: 20px;
    /* Space between cards */
}

/* Card Content Padding */
.card-content {
    padding: 20px;
}

/* Card Header */
.card-header {
    margin: 0;
    font-size: 1.2rem;
    background-color: #f5f5f5;
    padding: 15px;
    border-bottom: 1px solid #ddd;
    color: #333;
    font-weight: bold;
    display: flex;
    align-items: center;
}

/* Access Key Container (Global) */
.access-key-container {
    padding: 0 0 10px 0;
    /* Space below access key before card */
    display: flex;
    align-items: center;
    gap: 10px;
}

/* Specific adjustments for lists inside cards if needed */
.card ul {
    padding-left: 35px;
    /* Default list padding */
}

aside ul {
    list-style: none;
    padding: 20px;
    margin: 0;
}

aside ul li {
    margin-bottom: 10px;
}

aside ul li a {
    text-decoration: none;
    color: #333;
    display: block;
    padding: 8px;
    border-left: 3px solid transparent;
}

aside ul li a:hover,
aside ul li a:focus {
    border-left: 3px solid #005fcc;
    background-color: #ddd;
}

/* Full Width Main Content Override */
.full-width-main {
    width: 100% !important;
    max-width: 100% !important;
}

/* Breadcrumb */
.breadcrumb {
    padding: 10px 20px;
    background-color: transparent;
    font-size: 0.95rem;
    color: #555;
    margin-bottom: 0;
}

.breadcrumb a {
    text-decoration: none;
    color: #004488;
}

.breadcrumb a:hover {
    text-decoration: underline;
}

.breadcrumb span {
    margin: 0 5px;
    color: #999;
}

/* Responsive Layout Logic */
/* Mobile First implies default styles are for mobile, but here we define the split for Desktop */

/* Default: Stacked (Mobile) - Both take 100% implicitly or explicitly */
aside,
main {
    width: 100%;
}

/* Desktop: 1:3 Ratio */
@media (min-width: 768px) {
    aside {
        width: 25%;
        /* 1 part */
    }

    main {
        width: calc(75% - 20px);
        /* 3 parts, accounting for gap */
    }
}

/* Footer */
footer {
    background-color: #333;
    color: #fff;
    padding: 20px;
    text-align: center;
    margin-top: auto;
    /* Push to bottom if content is short */
}

footer .access-key {
    color: #ccc;
}

footer p {
    margin: 5px 0;
}