/* Google Font */
@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@300;400;500;600;700&display=swap');

:root{
    --primary:#2563eb;
    --primary-dark:#1d4ed8;
    --secondary:#1e293b;
    --success:#16a34a;
    --danger:#dc2626;
    --warning:#f59e0b;
    --light:#f8fafc;
    --white:#ffffff;
    --gray:#64748b;
    --border:#e2e8f0;
    --shadow:0 8px 25px rgba(0,0,0,.08);
    --radius:12px;
}

*{
    margin:0;
    padding:0;
    box-sizing:border-box;
    font-family:'Poppins',sans-serif;
}

body{
    background:var(--light);
    color:#222;
}

a{
    text-decoration:none;
}

ul{
    list-style:none;
}

.sidebar{
    position:fixed;
    left:0;
    top:0;
    width:250px;
    height:100vh;
    background:var(--secondary);
    color:#fff;
    padding:25px;
}

.sidebar h2{
    text-align:center;
    margin-bottom:40px;
    font-size:28px;
}

.sidebar ul li{
    margin-bottom:10px;
}

.sidebar ul li a{
    display:block;
    padding:14px 18px;
    color:#fff;
    border-radius:10px;
    transition:.3s;
}

.sidebar ul li a:hover{
    background:var(--primary);
    transform:translateX(5px);
}

.content{
    margin-left:250px;
    padding:40px;
}

.content h1{
    margin-bottom:10px;
}

.content h3{
    color:var(--gray);
    font-weight:500;
}

.cards{
    display:grid;
    grid-template-columns:repeat(auto-fit,minmax(230px,1fr));
    gap:25px;
    margin-top:35px;
}

.card{
    background:#fff;
    border-radius:var(--radius);
    padding:25px;
    box-shadow:var(--shadow);
    transition:.3s;
}

.card:hover{
    transform:translateY(-8px);
}

.card h2{
    font-size:35px;
    color:var(--primary);
}

.card p{
    margin-top:10px;
    color:var(--gray);
}

.container{
    width:420px;
    margin:70px auto;
    background:var(--white);
    padding:40px;
    border-radius:16px;
    box-shadow:var(--shadow);
}

.container h2{
    text-align:center;
    margin-bottom:30px;
    color:var(--secondary);
}

form{
    margin-top:20px;
}

input,
select,
textarea{
    width:100%;
    padding:14px 16px;
    margin-bottom:18px;
    border:1px solid var(--border);
    border-radius:10px;
    outline:none;
    font-size:15px;
    transition:.3s;
    background:#fff;
}

input:focus,
select:focus,
textarea:focus{
    border-color:var(--primary);
    box-shadow:0 0 0 3px rgba(37,99,235,.15);
}

textarea{
    resize:vertical;
    min-height:120px;
}

input[type="file"]{
    padding:12px;
}

button,
.btn{
    display:inline-block;
    width:100%;
    background:var(--primary);
    color:#fff;
    border:none;
    padding:14px;
    border-radius:10px;
    cursor:pointer;
    font-size:16px;
    font-weight:600;
    transition:.3s;
}

button:hover,
.btn:hover{
    background:var(--primary-dark);
    transform:translateY(-2px);
}

.success,
.error{
    padding:15px;
    border-radius:10px;
    margin-bottom:20px;
    font-weight:500;
}

.success{
    background:#dcfce7;
    color:#166534;
}

.error{
    background:#fee2e2;
    color:#991b1b;
}

table{
    width:100%;
    margin-top:25px;
    border-collapse:collapse;
    background:#fff;
    border-radius:12px;
    overflow:hidden;
    box-shadow:var(--shadow);
}

table th{
    background:var(--primary);
    color:#fff;
    padding:16px;
    text-align:left;
}

table td{
    padding:15px;
    border-bottom:1px solid #eee;
}

table tr:hover{
    background:#f8fafc;
}

table a{
    color:var(--primary);
    font-weight:600;
}

.card{
    position:relative;
    overflow:hidden;
}

.card::before{
    content:'';
    position:absolute;
    top:0;
    left:0;
    width:5px;
    height:100%;
    background:var(--primary);
}

.card h2{
    font-size:40px;
    font-weight:700;
}

.card p{
    font-size:15px;
    margin-top:10px;
}
.hero{
    min-height:100vh;
    background:linear-gradient(135deg,#2563eb,#1d4ed8);
    color:#fff;
}

nav{
    display:flex;
    justify-content:space-between;
    align-items:center;
    padding:25px 8%;
}

.nav-btn{
    color:#fff;
    margin-left:15px;
    padding:10px 20px;
    border:1px solid rgba(255,255,255,.3);
    border-radius:8px;
}

.register-btn{
    background:#fff;
    color:#2563eb;
}

.hero-content{
    text-align:center;
    max-width:800px;
    margin:120px auto;
    padding:20px;
}

.hero-content h1{
    font-size:60px;
    margin-bottom:20px;
}

.hero-content p{
    font-size:20px;
    line-height:1.8;
    margin-bottom:30px;
}

.hero-buttons{
    display:flex;
    justify-content:center;
    gap:20px;
}

.hero-buttons .btn{
    width:auto;
    padding:15px 30px;
}
.features{
    background:#fff;
    color:#333;
    padding:80px 8%;
    text-align:center;
}

.features h2{
    margin-bottom:50px;
    font-size:36px;
}

.feature-grid{
    display:grid;
    grid-template-columns:repeat(auto-fit,minmax(250px,1fr));
    gap:25px;
}

.feature-card{
    background:#f8fafc;
    padding:30px;
    border-radius:15px;
    box-shadow:0 5px 15px rgba(0,0,0,.05);
    transition:.3s;
}

.feature-card:hover{
    transform:translateY(-10px);
}

.feature-card h3{
    margin-bottom:15px;
    color:#2563eb;
}
.about{
    padding:80px 15%;
    text-align:center;
    background:#f1f5f9;
}

.about h2{
    margin-bottom:20px;
    font-size:36px;
}

.about p{
    font-size:18px;
    line-height:1.8;
    color:#555;
}

footer{
    background:#1e293b;
    color:#fff;
    text-align:center;
    padding:25px;
}

.dashboard-header{
    background:white;
    padding:30px;
    border-radius:15px;
    margin-bottom:30px;
    box-shadow:var(--shadow);
}

.dashboard-header h1{
    margin-bottom:10px;
}

.dashboard-header p{
    color:#64748b;
}
.users-card{
    border-left:5px solid #2563eb;
}

.students-card{
    border-left:5px solid #16a34a;
}

.lecturers-card{
    border-left:5px solid #f59e0b;
}

.courses-card{
    border-left:5px solid #dc2626;
}

.dashboard-grid{
    margin-top:30px;
}

.dashboard-box{
    background:white;
    padding:25px;
    border-radius:15px;
    box-shadow:var(--shadow);
}

.dashboard-box h3{
    margin-bottom:20px;
}

/* =========================================================
   RESPONSIVE DESIGN
   ========================================================= */

/* Tablets */
@media (max-width: 992px){

    .sidebar{
        width:210px;
        padding:20px 15px;
    }

    .sidebar h2{
        font-size:24px;
        margin-bottom:30px;
    }

    .sidebar ul li a{
        padding:12px 14px;
        font-size:14px;
    }

    .content{
        margin-left:210px;
        padding:25px;
    }

    .cards{
        grid-template-columns:repeat(2,1fr);
        gap:18px;
    }

    .hero-content{
        margin:80px auto;
    }

    .hero-content h1{
        font-size:48px;
    }

    .hero-content p{
        font-size:18px;
    }

    .about{
        padding:70px 10%;
    }

    .features{
        padding:70px 6%;
    }
}


/* Mobile Devices */
@media (max-width: 768px){

    /* Sidebar becomes top navigation */
    .sidebar{
        position:relative;
        width:100%;
        height:auto;
        padding:15px;
    }

    .sidebar h2{
        margin-bottom:15px;
        font-size:23px;
    }

    .sidebar ul{
        display:flex;
        flex-wrap:wrap;
        justify-content:center;
        gap:8px;
    }

    .sidebar ul li{
        margin-bottom:0;
    }

    .sidebar ul li a{
        padding:9px 12px;
        font-size:13px;
    }

    .sidebar ul li a:hover{
        transform:none;
    }

    /* Main content */
    .content{
        margin-left:0;
        padding:20px 15px;
    }

    .content h1{
        font-size:26px;
    }

    .content h3{
        font-size:16px;
    }

    /* Cards */
    .cards{
        grid-template-columns:1fr;
        gap:15px;
        margin-top:25px;
    }

    .card{
        padding:20px;
    }

    .card h2{
        font-size:32px;
    }

    /* Forms */
    .container{
        width:calc(100% - 30px);
        max-width:420px;
        margin:35px auto;
        padding:25px 20px;
    }

    .container h2{
        font-size:24px;
        margin-bottom:20px;
    }

    input,
    select,
    textarea{
        font-size:14px;
        padding:13px 14px;
    }

    button,
    .btn{
        font-size:15px;
        padding:13px;
    }

    /* Tables */
    table{
        display:block;
        overflow-x:auto;
        white-space:nowrap;
        font-size:13px;
    }

    table th,
    table td{
        padding:11px;
    }

    /* Hero */
    nav{
        padding:18px 5%;
        flex-direction:column;
        gap:15px;
    }

    .nav-btn{
        margin-left:5px;
        padding:8px 14px;
        font-size:14px;
    }

    .hero-content{
        margin:50px auto;
        padding:20px 15px;
    }

    .hero-content h1{
        font-size:40px;
        line-height:1.2;
    }

    .hero-content p{
        font-size:16px;
        line-height:1.6;
    }

    .hero-buttons{
        flex-direction:column;
        gap:12px;
        align-items:center;
    }

    .hero-buttons .btn{
        width:100%;
        max-width:300px;
        padding:13px 20px;
    }

    /* Features */
    .features{
        padding:55px 20px;
    }

    .features h2{
        font-size:28px;
        margin-bottom:35px;
    }

    .feature-grid{
        grid-template-columns:1fr;
        gap:18px;
    }

    .feature-card{
        padding:25px 20px;
    }

    /* About */
    .about{
        padding:55px 20px;
    }

    .about h2{
        font-size:28px;
    }

    .about p{
        font-size:16px;
        line-height:1.7;
    }

    /* Dashboard */
    .dashboard-header{
        padding:20px;
        margin-bottom:20px;
    }

    .dashboard-header h1{
        font-size:25px;
    }

    .dashboard-header p{
        font-size:14px;
    }

    .dashboard-box{
        padding:20px;
    }

    .dashboard-box h3{
        font-size:18px;
    }
}


/* Small Phones */
@media (max-width: 480px){

    .sidebar{
        padding:12px 10px;
    }

    .sidebar h2{
        font-size:21px;
    }

    .sidebar ul{
        gap:5px;
    }

    .sidebar ul li a{
        padding:8px 9px;
        font-size:12px;
    }

    .content{
        padding:15px 12px;
    }

    .content h1{
        font-size:23px;
    }

    .content h3{
        font-size:14px;
    }

    .card{
        padding:18px;
    }

    .card h2{
        font-size:28px;
    }

    .card p{
        font-size:14px;
    }

    .container{
        width:calc(100% - 20px);
        padding:22px 16px;
        margin:25px auto;
    }

    .container h2{
        font-size:21px;
    }

    .hero-content{
        margin:35px auto;
        padding:15px;
    }

    .hero-content h1{
        font-size:32px;
    }

    .hero-content p{
        font-size:15px;
    }

    nav{
        padding:15px 4%;
    }

    .nav-btn{
        padding:7px 10px;
        font-size:12px;
    }

    .features{
        padding:45px 15px;
    }

    .features h2,
    .about h2{
        font-size:25px;
    }

    footer{
        padding:20px 15px;
        font-size:13px;
    }
}


/* Prevent long text/URLs from breaking mobile layouts */
body{
    overflow-x:hidden;
}

img{
    max-width:100%;
    height:auto;
}

button,
input,
select,
textarea{
    max-width:100%;
}