/* Reset cơ bản */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* Body */
body {
    font-family: Arial, Helvetica, sans-serif;
    background: #0f172a;
    color: white;
    min-height: 100vh;
    padding: 40px 20px;
}

/* Dashboard */
.dashboard {
    width: 100%;
    max-width: 1200px;
    margin: auto;

    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 25px;
}

/* Panel */
.panel {
    background: #1e293b;
    border: 1px solid rgba(255,255,255,0.08);
    border-radius: 18px;
    overflow: hidden;

    transition: all 0.3s ease;
    box-shadow: 0 8px 20px rgba(0,0,0,0.25);
}

/* Hover */
.panel:hover {
    transform: translateY(-6px);
    border-color: #38bdf8;
    box-shadow: 0 12px 30px rgba(56,189,248,0.25);
}

/* Header */
.panel-header {
    display: flex;
    justify-content: space-between;
    align-items: center;

    padding: 18px 20px;
    background: linear-gradient(135deg, #0ea5e9, #2563eb);
}

/* Title */
.panel-title {
    font-size: 22px;
    font-weight: bold;
    letter-spacing: 1px;
}

/* Status */
.live {
    background: rgba(255,255,255,0.2);
    padding: 6px 12px;
    border-radius: 30px;

    font-size: 12px;
    font-weight: bold;
    color: #fff;
}

/* Content */
.panel-content {
    padding: 20px;

    display: flex;
    flex-direction: column;
    gap: 14px;
}

/* Link bài tập */
.panel-content a {
    text-decoration: none;
    color: #e2e8f0;

    background: #334155;
    padding: 12px 16px;
    border-radius: 10px;

    transition: all 0.25s ease;
    font-size: 15px;
}

/* Hover link */
.panel-content a:hover {
    background: #38bdf8;
    color: #0f172a;
    transform: translateX(5px);
}

/* Responsive điện thoại */
@media (max-width: 768px) {
    body {
        padding: 20px 15px;
    }

    .panel-title {
        font-size: 18px;
    }

    .live {
        font-size: 10px;
        padding: 5px 10px;
    }
}