@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@300;400;600;700&display=swap');

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

body {
    font-family: 'Poppins', sans-serif;
    min-height: 100vh;
    background: linear-gradient(135deg, #165ca1, #2006e5);
    color: white;
}

/* Sidebar */
.sidebar {
    position: fixed;
    left: 0;
    top: 0;
    width: 240px;
    height: 100vh;
    background: rgba(0, 0, 0, 0.25);
    backdrop-filter: blur(10px);
    box-shadow: 4px 0 20px rgba(0, 0, 0, 0.2);
    padding: 30px 20px;
}

.sidebar h2 {
    font-size: 1.4rem;
    margin-bottom: 25px;
}

.sidebar nav ul {
    list-style: none;
}

.sidebar nav ul li {
    margin-bottom: 14px;
}

.sidebar nav ul li a {
    text-decoration: none;
    color: white;
    opacity: 0.9;
    transition: 0.25s ease;
}

.sidebar nav ul li a:hover {
    opacity: 1;
    padding-left: 6px;
}

/* Main content */
.main-content {
    min-height: 100vh;
    margin-left: 240px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    padding: 40px;
}

/* Shared container */
.container {
    background: rgba(255, 255, 255, 0.12);
    backdrop-filter: blur(12px);
    padding: 40px;
    border-radius: 24px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.25);
    width: 100%;
    max-width: 1000px;
    margin-bottom: 30px;
}

.container h1 {
    font-size: 2.4rem;
    margin-bottom: 10px;
}

.subtitle {
    font-size: 1rem;
    opacity: 0.85;
    margin-bottom: 25px;
}

/* Button */
.btn {
    display: inline-block;
    text-decoration: none;
    background: white;
    color: #165ca1;
    font-weight: 600;
    padding: 14px 26px;
    border-radius: 14px;
    transition: 0.25s ease;
}

.btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 24px rgba(0, 0, 0, 0.2);
}

/* Index page link cards */
.link-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
    margin-top: 20px;
}

.link-card {
    display: block;
    text-decoration: none;
    color: white;
    background: rgba(255, 255, 255, 0.12);
    border-radius: 18px;
    padding: 22px 20px;
    font-weight: 600;
    text-align: center;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.18);
    transition: 0.25s ease;
}

.link-card:hover {
    transform: translateY(-4px);
    background: rgba(255, 255, 255, 0.18);
}

/* IoT sensor cards */
.sensor-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
    margin-top: 20px;
}

.sensor-card {
    background: rgba(255, 255, 255, 0.12);
    border-radius: 18px;
    padding: 25px 20px;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
}

.sensor-card h2 {
    font-size: 1.2rem;
    margin-bottom: 15px;
}

.value {
    font-size: 2rem;
    font-weight: 700;
}

/* Responsive */
@media (max-width: 900px) {
    .sidebar {
        position: relative;
        width: 100%;
        height: auto;
        box-shadow: none;
    }

    .main-content {
        margin-left: 0;
        padding: 20px;
    }

    .link-grid,
    .sensor-grid {
        grid-template-columns: 1fr;
    }

    .container {
        padding: 28px 20px;
    }

    .container h1 {
        font-size: 2rem;
    }
}