* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    color: #333;
    background: #fff;
}

/* Header */
.header {
    background: #fff;
    border-bottom: 3px solid #e87722;
    padding: 12px 30px;
    display: flex;
    align-items: center;
    gap: 20px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    text-decoration: none;
    color: inherit;
}

.logo-box {
    border: 2px solid #1a1a6e;
    padding: 6px 12px;
    display: flex;
    align-items: center;
    gap: 10px;
    background: #fff;
}

.logo-vit {
    font-size: 32px;
    font-weight: 900;
    color: #1a1a6e;
    letter-spacing: 2px;
    line-height: 1;
}

.logo-text {
    font-size: 11px;
    color: #1a1a6e;
    line-height: 1.3;
    font-weight: 600;
}

.logo-accredited {
    font-size: 9px;
    color: #555;
    font-style: italic;
    margin-top: 2px;
}

.logo-subtitle {
    font-size: 9px;
    color: #333;
    text-align: center;
    margin-top: 4px;
}

.header-title {
    font-size: 20px;
    color: #2874a6;
    font-weight: 600;
    margin-left: auto;
}

/* Discipline bar */
.discipline-bar {
    background: #f8f9fa;
    padding: 10px 30px;
    border-bottom: 1px solid #ddd;
}

.discipline-bar h2 {
    color: #2874a6;
    font-size: 18px;
    font-weight: 600;
}

/* Layout */
.container {
    display: flex;
    min-height: calc(100vh - 140px);
}

/* Sidebar */
.sidebar {
    width: 220px;
    min-width: 220px;
    border-right: 1px solid #ddd;
    padding: 20px 0;
    background: #fff;
}

.sidebar a {
    display: block;
    padding: 10px 20px;
    color: #333;
    text-decoration: none;
    font-size: 15px;
    border-left: 3px solid transparent;
    transition: all 0.2s;
}

.sidebar a:hover {
    color: #e87722;
    background: #fef5ed;
    border-left-color: #e87722;
}

.sidebar a.active {
    color: #e87722;
    font-weight: 600;
    border-left-color: #e87722;
    background: #fef5ed;
}

/* Main content */
.content {
    flex: 1;
    padding: 40px 50px;
}

.content h1 {
    color: #2874a6;
    font-size: 26px;
    font-weight: 500;
    text-align: center;
    margin-bottom: 30px;
}

.content p {
    font-size: 15px;
    line-height: 1.8;
    color: #444;
    margin-bottom: 16px;
}

.content ul {
    margin: 10px 0 20px 25px;
}

.content ul li {
    font-size: 15px;
    line-height: 1.8;
    color: #444;
    margin-bottom: 6px;
}

.content table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
}

.content table th,
.content table td {
    border: 1px solid #ddd;
    padding: 10px 14px;
    text-align: left;
    font-size: 14px;
}

.content table th {
    background: #2874a6;
    color: #fff;
    font-weight: 600;
}

.content table tr:nth-child(even) {
    background: #f8f9fa;
}

/* Experiment list */
.experiment-list {
    list-style: none;
    margin: 0;
    padding: 0;
}

.experiment-list li {
    padding: 14px 20px;
    border: 1px solid #ddd;
    border-radius: 6px;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 12px;
    transition: all 0.2s;
}

.experiment-list li:hover {
    border-color: #2874a6;
    background: #f0f7fc;
}

.experiment-list li a {
    color: #2874a6;
    text-decoration: none;
    font-size: 15px;
    font-weight: 500;
}

.experiment-list li a:hover {
    text-decoration: underline;
}

.experiment-number {
    background: #2874a6;
    color: #fff;
    width: 30px;
    height: 30px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    font-weight: 600;
    flex-shrink: 0;
}

/* Footer */
.footer {
    background: #2c3e50;
    color: #ccc;
    text-align: center;
    padding: 15px;
    font-size: 13px;
    border-top: 3px solid #e87722;
}

/* Responsive */
@media (max-width: 768px) {
    .container {
        flex-direction: column;
    }

    .sidebar {
        width: 100%;
        min-width: 100%;
        border-right: none;
        border-bottom: 1px solid #ddd;
        padding: 10px 0;
        display: flex;
        overflow-x: auto;
    }

    .sidebar a {
        white-space: nowrap;
        border-left: none;
        border-bottom: 3px solid transparent;
    }

    .sidebar a.active {
        border-left: none;
        border-bottom-color: #e87722;
    }

    .content {
        padding: 20px;
    }

    .header {
        flex-direction: column;
        text-align: center;
    }

    .header-title {
        margin-left: 0;
    }
}