@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+KR:wght@300;400;500;700&display=swap');

:root {
    --primary-color: #3b82f6;
    --primary-hover: #2563eb;
    --danger-color: #ef4444;
    --warning-color: #f59e0b;
    --success-color: #10b981;
    --text-color: #1f2937;
    --bg-color: #f9fafb;
    --border-color: #e5e7eb;
    --white: #ffffff;
    --table-header-bg: #f3f4f6;
    --row-hover: #f9fafb;
}

* {
    box-sizing: border-box;
    font-family: 'Noto Sans KR', sans-serif;
}

body {
    margin: 0;
    padding: 20px;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.5;
}

a {
    text-decoration: none;
    color: inherit;
    transition: color 0.2s;
}

a:hover {
    color: var(--primary-color);
}

.report-container {
    max-width: 1200px;
    margin: 0 auto;
    background: var(--white);
    padding: 30px;
    border-radius: 12px;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
}

h1.page-title {
    font-size: 1.875rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 1rem;
    color: #111827;
}

.status-summary {
    text-align: center;
    font-size: 1.125rem;
    color: #4b5563;
    margin-bottom: 2rem;
}

/* Updated Table Layout using CSS Grid */
.report-grid {
    display: grid;
    /* Define columns: Class/No (narrow) | Link (wide) | Expire (medium) | Submit (medium) | Eval (narrow) */
    grid-template-columns: 80px 1fr 180px 180px 100px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    overflow: hidden;
}

.grid-header {
    display: contents;
    font-weight: 600;
    background-color: var(--table-header-bg);
    color: #374151;
}

.grid-header>div {
    background-color: var(--table-header-bg);
    /* Apply background to cells for "sticky" effect capability if needed later */
    padding: 12px 16px;
    text-align: center;
    border-bottom: 2px solid var(--border-color);
}

.grid-row {
    display: contents;
}

.grid-row>div {
    padding: 12px 16px;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    /* Vertical center */
    font-size: 0.95rem;
}

.grid-row:last-child>div {
    border-bottom: none;
}

.grid-row:hover>div {
    background-color: var(--row-hover);
}

/* Column specific alignments */
.col-center {
    justify-content: center;
    text-align: center;
}

.col-left {
    justify-content: flex-start;
    text-align: left;
}

/* Status Highlights */
.bg-warning>div {
    background-color: #fffbeb;
}

/* Light yellow */
.bg-danger>div {
    background-color: #fef2f2;
}

/* Light red */

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 6px 12px;
    border-radius: 6px;
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    border: none;
    transition: all 0.2s;
    text-decoration: none;
}

.btn-xs {
    padding: 4px 10px;
    font-size: 0.8rem;
}

.btn-primary {
    background-color: var(--primary-color);
    color: white;
}

.btn-primary:hover {
    background-color: var(--primary-hover);
    color: white;
}

.btn-success {
    background-color: var(--success-color);
    color: white;
}

.btn-success:hover {
    filter: brightness(90%);
    color: white;
}

.btn-default {
    background-color: #e5e7eb;
    color: #374151;
}

.btn-default:hover {
    background-color: #d1d5db;
}

.btn:disabled,
.btn[disabled] {
    opacity: 0.5;
    cursor: not-allowed;
    background-color: #e5e7eb;
    color: #9ca3af;
}

/* Nav for Year Selection */
.year-nav ul {
    list-style: none;
    padding: 0;
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    justify-content: center;
    margin-bottom: 20px;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 10px;
}

.year-nav li a {
    display: block;
    padding: 8px 16px;
    border-radius: 20px;
    background-color: #f3f4f6;
    color: #4b5563;
}

.year-nav li a:hover,
.year-nav li.active a {
    background-color: var(--primary-color);
    color: white;
}

/* Student List Grid (for default mode) */
.student-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 15px;
    margin-top: 20px;
}

.student-card {
    background: #f9fafb;
    padding: 5px;
    border-radius: 8px;
    text-align: center;
    border: 1px solid var(--border-color);
}

.student-card a {
    font-weight: 500;
    color: var(--primary-color);
}

.class-header {
    width: 100%;
    margin-top: 30px;
    margin-bottom: 10px;
    padding-bottom: 5px;
    border-bottom: 2px solid var(--border-color);
    font-size: 1.25rem;
    font-weight: 600;
    color: #374151;
}

/* Typography Helpers */
.text-danger {
    color: var(--danger-color);
    font-weight: bold;
}

.text-primary {
    color: var(--primary-color);
    font-weight: bold;
}

.font-bold {
    font-weight: bold;
}

.username {
    font-weight: bold;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

/* Responsive */
@media (max-width: 768px) {
    .report-grid {
        grid-template-columns: 80px 1fr 90px;
    }

    .grid-header>div:nth-child(4),
    /* Submit info */
    .grid-row>div:nth-child(4) {
        display: none;
        /* Hide file size/submit date on mobile to save space, or stack it */
    }

    /* Make buttons column smaller */
    .report-grid {
        grid-template-columns: 50px 1fr 80px 60px;
        /* Adjusted columns */
    }

    .grid-header>div,
    .grid-row>div {
        padding: 8px 4px;
        font-size: 0.85rem;
    }
}