:root {
    --primary: #1b56fd;
    --primary-dark: #1340c4;
    --accent: #00c2a8;
    --bg: #f4f6fb;
    --text: #1c2333;
    --muted: #6b7280;
    --card: #ffffff;
    --border: #e3e7ef;
}

* { box-sizing: border-box; }

body {
    margin: 0;
    font-family: 'Segoe UI', Roboto, Arial, sans-serif;
    background: var(--bg);
    color: var(--text);
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: var(--card);
    padding: 16px 32px;
    border-bottom: 1px solid var(--border);
}

.navbar .logo {
    font-weight: 800;
    font-size: 22px;
    color: var(--primary);
    text-decoration: none;
}

.navbar a.btn {
    text-decoration: none;
}

.auth-wrap {
    max-width: 420px;
    margin: 60px auto;
    background: var(--card);
    padding: 36px;
    border-radius: 14px;
    box-shadow: 0 10px 30px rgba(20,30,60,0.08);
}

.auth-wrap h1 {
    margin-top: 0;
    font-size: 24px;
}

.auth-wrap p.sub {
    color: var(--muted);
    margin-top: -8px;
    margin-bottom: 24px;
    font-size: 14px;
}

label {
    display: block;
    font-size: 13px;
    font-weight: 600;
    margin: 14px 0 6px;
}

input[type=text], input[type=email], input[type=tel], input[type=password], input[type=file], select {
    width: 100%;
    padding: 11px 12px;
    border: 1px solid var(--border);
    border-radius: 8px;
    font-size: 14px;
    background: #fafbfd;
}

input:focus, select:focus {
    outline: none;
    border-color: var(--primary);
    background: #fff;
}

.btn {
    display: inline-block;
    background: var(--primary);
    color: #fff;
    border: none;
    padding: 12px 20px;
    border-radius: 8px;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    margin-top: 20px;
    width: 100%;
    text-align: center;
}

.btn:hover { background: var(--primary-dark); }

.btn.secondary {
    background: transparent;
    color: var(--primary);
    border: 1px solid var(--primary);
}

.error-box {
    background: #fdecec;
    color: #b42318;
    border: 1px solid #f5b5b1;
    padding: 10px 14px;
    border-radius: 8px;
    font-size: 13px;
    margin-bottom: 10px;
}

.success-box {
    background: #e8f9f1;
    color: #0a7a52;
    border: 1px solid #aee8cc;
    padding: 10px 14px;
    border-radius: 8px;
    font-size: 13px;
    margin-bottom: 10px;
}

.switch-link {
    text-align: center;
    font-size: 14px;
    margin-top: 18px;
    color: var(--muted);
}

.switch-link a { color: var(--primary); font-weight: 600; text-decoration: none; }

.container {
    max-width: 1000px;
    margin: 40px auto;
    padding: 0 20px;
}

.category-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 20px;
    margin-top: 20px;
}

.cat-card {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 14px;
    padding: 24px;
}

.cat-card h3 {
    margin-top: 0;
    color: var(--primary-dark);
}

.test-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 0;
    border-bottom: 1px solid var(--border);
}

.test-item:last-child { border-bottom: none; }

.test-item a.open {
    background: var(--accent);
    color: #fff;
    padding: 6px 14px;
    border-radius: 6px;
    text-decoration: none;
    font-size: 13px;
}

table {
    width: 100%;
    border-collapse: collapse;
    background: var(--card);
    border-radius: 10px;
    overflow: hidden;
}

th, td {
    text-align: left;
    padding: 10px 14px;
    border-bottom: 1px solid var(--border);
    font-size: 14px;
}

th { background: #eef1fa; }

.badge {
    padding: 3px 10px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
    color: #fff;
}
.badge.listening { background: #1b56fd; }
.badge.reading { background: #00c2a8; }
.badge.writing { background: #f59e0b; }