:root {
    --primary: #4f46e5;
    --primary-hover: #4338ca;
    --bg-dark: #0f172a;
    --bg-card: #1e293b;
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --border: #334155;
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-dark);
    color: var(--text-main);
    margin: 0;
    padding: 0;
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
}

/* Glassmorphism Card */
.card {
    background: rgba(30, 41, 59, 0.7);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border);
    border-radius: 1rem;
    padding: 2rem;
    margin-bottom: 2rem;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

h1, h2, h3 {
    font-weight: 700;
    letter-spacing: -0.025em;
}

h1 { font-size: 2.5rem; margin-bottom: 1rem; }
h2 { font-size: 1.5rem; margin-bottom: 1.5rem; color: var(--text-muted); }

/* Forms */
.form-group {
    margin-bottom: 1.5rem;
}

label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--text-muted);
    font-size: 0.875rem;
}

input[type="text"],
input[type="password"],
textarea,
select {
    width: 100%;
    padding: 0.75rem;
    background: var(--bg-dark);
    border: 1px solid var(--border);
    border-radius: 0.5rem;
    color: var(--text-main);
    font-size: 1rem;
    transition: border-color 0.2s;
}

input:focus, textarea:focus {
    outline: none;
    border-color: var(--primary);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.5rem;
    border-radius: 0.5rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    border: none;
    text-decoration: none;
}

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

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

.btn-secondary {
    background-color: var(--bg-card);
    border: 1px solid var(--border);
    color: var(--text-main);
}

.btn-secondary:hover {
    background-color: var(--border);
}

/* Tables */
.table-container {
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
}

th, td {
    padding: 1rem;
    text-align: left;
    border-bottom: 1px solid var(--border);
}

th {
    color: var(--text-muted);
    font-weight: 600;
    font-size: 0.875rem;
    text-transform: uppercase;
}

/* Status Badges */
.badge {
    padding: 0.25rem 0.75rem;
    border-radius: 9999px;
    font-size: 0.75rem;
    font-weight: 600;
}

.badge-pending { background: rgba(245, 158, 11, 0.2); color: var(--warning); }
.badge-graded { background: rgba(16, 185, 129, 0.2); color: var(--success); }
.badge-failed { background: rgba(239, 68, 68, 0.2); color: var(--danger); }

/* Review Page Layout */
.review-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    height: calc(100vh - 100px);
}

.pdf-viewer {
    background: #000;
    border-radius: 1rem;
    overflow: hidden;
    height: 100%;
}

.grading-panel {
    overflow-y: auto;
    padding-right: 1rem;
}

.question-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 0.75rem;
    padding: 1.5rem;
    margin-bottom: 1rem;
}

.question-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.grade-input {
    width: 80px !important;
    text-align: right;
    font-weight: bold;
}

.system-note {
    background: rgba(79, 70, 229, 0.1);
    border-left: 3px solid var(--primary);
    padding: 0.75rem;
    margin: 1rem 0;
    font-size: 0.9rem;
    color: #c7d2fe;
}

.teacher-note {
    margin-top: 1rem;
}

/* Responsive */
@media (max-width: 768px) {
    .review-grid {
        grid-template-columns: 1fr;
        height: auto;
    }
}