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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #ffffff, #f4f6f9);
    color: #333;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Header */
header {
    background: linear-gradient(90deg, #d32f2f, #1976d2);
    color: white;
    padding: 15px 20px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.2);
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.header-container h1 {
    font-size: 1.2rem;
    font-weight: bold;
}

/* Home button */
.home-btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 15px;
    background: #ffffff;
    color: #d32f2f;
    text-decoration: none;
    border-radius: 6px;
    font-size: 0.95rem;
    font-weight: bold;
    transition: all 0.3s ease;
}

.home-btn:hover {
    background: #f4f4f4;
    transform: scale(1.05);
}

/* Search box */
.search-box {
    display: flex;
    justify-content: center;
    align-items: center;
    margin: 30px auto;
    width: 90%;
    max-width: 600px;
    gap: 10px;
}

.search-box input {
    flex: 1;
    padding: 12px;
    border: 2px solid #1976d2;
    border-radius: 8px;
    font-size: 1rem;
    transition: all 0.3s ease;
}

.search-box input:focus {
    border-color: #d32f2f;
    outline: none;
    box-shadow: 0 0 8px rgba(211,47,47,0.5);
}

.search-box button {
    padding: 12px 20px;
    background: #d32f2f;
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 8px;
}

.search-box button:hover {
    background: #b71c1c;
    transform: scale(1.05);
}

/* Result box */
.result-box {
    margin: 20px auto;
    width: 90%;
    max-width: 600px;
    border-radius: 12px;
    padding: 20px;
    background: white;
    box-shadow: 0 4px 12px rgba(0,0,0,0.1);
    animation: fadeIn 0.5s ease-in-out;
}

.result-box h2 {
    color: #1976d2;
    margin-bottom: 15px;
    font-size: 1.3rem;
    display: flex;
    align-items: center;
    gap: 8px;
}

.result-box h2 i {
    color: #d32f2f;
}

.student-info p {
    margin: 8px 0;
    font-size: 1rem;
    line-height: 1.4;
}

/* Highlight box cho mã sinh viên */
.highlight-box {
    background: #fef4f4;
    border: 2px solid #d32f2f;
    border-radius: 10px;
    padding: 12px;
    margin-bottom: 15px;
    box-shadow: 0 4px 10px rgba(211,47,47,0.2);
    font-size: 1.1rem;
    font-weight: bold;
    color: #d32f2f;
    text-align: center;
}

/* Footer */
footer {
    text-align: center;
    background: #1976d2;
    color: white;
    padding: 12px;
    margin-top: auto;
    font-size: 0.9rem;
}

/* Hiệu ứng */
@keyframes fadeIn {
    from {opacity: 0; transform: translateY(10px);}
    to {opacity: 1; transform: translateY(0);}
}

/* Responsive */
@media (max-width: 600px) {
    .search-box {
        flex-direction: column;
    }

    .search-box input, .search-box button {
        width: 100%;
    }
}