:root {
    --bg-body: #0b171d;
    --card-bg: #0f2027;
    --card-border: rgba(255, 255, 255, 0.08);
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --accent-blue: #38bdf8;
    --accent-green: #4ade80;
    --accent-red: #f87171;
    --accent-amber: #fbbf24;
    --sidebar-width: 260px;
}

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

.main-wrapper {
    margin-left: var(--sidebar-width);
    min-height: 100vh;
    transition: all 0.3s ease;
    width: calc(100% - var(--sidebar-width));
}

.content-container {
    padding: 30px;
    max-width: 1400px;
    width: 100%;
    margin: 0 auto;
}

.page-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 25px;
}

.page-title h2 {
    margin: 0;
    font-size: 24px;
    font-weight: 700;
    color: #fff;
    display: flex;
    align-items: center;
    gap: 10px;
}

.page-title p {
    margin: 5px 0 0 0;
    font-size: 14px;
    color: var(--text-muted);
}

.card-custom {
    background: var(--card-bg);
    border-radius: 16px;
    border: 1px solid var(--card-border);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.35);
    padding: 24px;
}

.filter-wrapper {
    display: flex;
    gap: 15px;
    margin-bottom: 20px;
    align-items: center;
    flex-wrap: wrap;
}

.filter-select {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--card-border);
    color: var(--text-main);
    padding: 8px 14px;
    border-radius: 10px;
    font-size: 14px;
    outline: none;
}

.filter-select option {
    background: #0f2027;
    color: #fff;
}

.dataTables_wrapper {
    color: var(--text-muted);
}

table.dataTable {
    border-collapse: collapse !important;
    margin-top: 15px !important;
    margin-bottom: 20px !important;
    width: 100% !important;
}

table.dataTable thead th {
    background: rgba(255, 255, 255, 0.03);
    color: #e2e8f0;
    font-weight: 600;
    font-size: 13px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    padding: 14px 16px;
    border-bottom: 1px solid var(--card-border) !important;
}

table.dataTable tbody td {
    background: transparent !important;
    color: #cbd5e1;
    padding: 16px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.04) !important;
    vertical-align: middle;
    font-size: 14px;
}

.dataTables_filter input {
    background: rgba(255, 255, 255, 0.05) !important;
    border: 1px solid var(--card-border) !important;
    color: #fff !important;
    border-radius: 8px !important;
    padding: 6px 12px !important;
    outline: none;
}

.dataTables_length select {
    background: rgba(255, 255, 255, 0.05) !important;
    border: 1px solid var(--card-border) !important;
    color: #fff !important;
    border-radius: 8px !important;
    padding: 4px 8px !important;
}

.page-item.active .page-link {
    background-color: #2563eb !important;
    border-color: #2563eb !important;
}

.page-link {
    background-color: rgba(255, 255, 255, 0.05) !important;
    border-color: var(--card-border) !important;
    color: #94a3b8 !important;
}

.badge-custom {
    padding: 6px 12px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.badge-type { background: rgba(56, 189, 248, 0.12); color: var(--accent-blue); border: 1px solid rgba(56, 189, 248, 0.25); }
.badge-approved { background: rgba(74, 222, 128, 0.12); color: var(--accent-green); border: 1px solid rgba(74, 222, 128, 0.25); }
.badge-pending { background: rgba(251, 191, 36, 0.12); color: var(--accent-amber); border: 1px solid rgba(251, 191, 36, 0.25); }
.badge-rejected { background: rgba(248, 113, 113, 0.12); color: var(--accent-red); border: 1px solid rgba(248, 113, 113, 0.25); }

.btn-action {
    border: none;
    padding: 8px 14px;
    border-radius: 8px;
    font-size: 13px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    text-decoration: none;
}

.btn-approve { background: #16a34a; color: #fff; }
.btn-approve:hover { background: #15803d; }
.btn-reject { background: #dc2626; color: #fff; }
.btn-reject:hover { background: #b91c1c; }
.btn-file { background: rgba(56, 189, 248, 0.15); color: var(--accent-blue); border: 1px solid rgba(56, 189, 248, 0.3); }
.btn-file:hover { background: #0284c7; color: #fff; }
.btn-chat { background: rgba(168, 85, 247, 0.15); color: #c084fc; border: 1px solid rgba(168, 85, 247, 0.3); }
.btn-chat:hover { background: #9333ea; color: #fff; }

.teacher-name { font-weight: 700; color: #fff; display: block; }
.teacher-id { font-size: 12px; color: var(--text-muted); }

/* Chat Modal & UI Styles */
.chat-box {
    max-height: 350px;
    overflow-y: auto;
    background: rgba(0, 0, 0, 0.2);
    border-radius: 10px;
    padding: 15px;
    border: 1px solid var(--card-border);
}

.chat-message {
    margin-bottom: 12px;
    padding: 10px 14px;
    border-radius: 10px;
    font-size: 13px;
    max-width: 80%;
}

.chat-td {
    background: rgba(37, 99, 235, 0.2);
    border: 1px solid rgba(37, 99, 235, 0.3);
    margin-left: auto;
    color: #e2e8f0;
}

.chat-teacher {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--card-border);
    margin-right: auto;
    color: #cbd5e1;
}

.swal2-popup-dark {
    background: #0f2027 !important;
    border: 1px solid var(--card-border) !important;
    border-radius: 20px !important;
    color: #fff !important;
    box-shadow: 0 20px 50px rgba(0,0,0,0.6) !important;
}
.swal2-title { color: #fff !important; font-size: 20px !important; }
.swal2-html-container { color: #94a3b8 !important; }

@media (max-width: 992px) {
    .main-wrapper {
        margin-left: 0 !important;
        width: 100% !important;
    }
}