/* --- 1. Reset ค่าเริ่มต้น --- */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* --- 2. หน้าหลัก (Body) จัดให้อยู่กลางจอ --- */
body {
    width: 100%;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    background-color: #f8f9fa;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    color: #333;
}

/* --- 3. Container หลัก (หน้า Index) --- */
.container {
    text-align: center;
    background: #ffffff;
    padding: 3rem;
    border-radius: 12px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    width: 90%;
    max-width: 400px;
    margin: 0 auto;
}

.container h1 {
    font-size: 1.8rem;
    color: #2c3e50;
    margin-bottom: 0.5rem;
}

.container p {
    color: #7f8c8d;
    margin-bottom: 2rem;
}

/* --- 4. ปุ่มเข้าสู่ระบบ (หน้า Index) --- */
#btn-to-login {
    background-color: #2980b9;
    color: white;
    border: none;
    padding: 12px 30px;
    font-size: 1rem;
    font-weight: 600;
    border-radius: 6px;
    cursor: pointer;
    transition: background 0.3s ease;
}

#btn-to-login:hover {
    background-color: #3498db;
}

/* --- 5. กล่อง Login (ที่จะถูกโหลดเข้ามา) --- */
.login-container {
    background: #ffffff;
    padding: 40px;
    border-radius: 16px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    width: 100%;
    max-width: 350px;
    text-align: center;
}

.login-header h1 {
    font-size: 1.5rem;
    color: #2c3e50;
    margin-bottom: 5px;
}

.login-header p {
    color: #95a5a6;
    margin-bottom: 25px;
    font-size: 0.9rem;
}

.input-group {
    margin-bottom: 20px;
}

.input-group input {
    width: 100%;
    padding: 12px 15px;
    border: 1px solid #ddd;
    border-radius: 8px;
    font-size: 1rem;
    outline: none;
    transition: border 0.3s;
}

.input-group input:focus {
    border-color: #0984e3;
}

.btn {
    width: 100%;
    background-color: #0984e3;
    color: white;
    border: none;
    padding: 12px;
    font-size: 1rem;
    font-weight: 600;
    border-radius: 8px;
    cursor: pointer;
    transition: 0.3s;
}

.btn:hover {
    background-color: #0773c5;
}

#main-content {
    width: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    margin-top: 20px;
}