/* HUST Booking SaaS - Web Styles (Dark Theme) */
:root {
    --bg: #1c1c1c;
    --card: #2d2d2d;
    --card-hover: #333333;
    --border: #3d3d3d;
    --text: #ffffff;
    --text-secondary: #c5c5c5;
    --text-muted: #9d9d9d;
    --accent: #60cdff;
    --accent-hover: #78d4ff;
    --success: #6ccb5f;
    --warning: #fce100;
    --error: #ff99a4;
    --radius: 12px;
    --radius-sm: 8px;
}

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

body {
    font-family: "Segoe UI Variable", "Segoe UI", "Microsoft YaHei UI", sans-serif;
    background: var(--bg);
    color: var(--text);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
}

.container {
    width: 100%;
    max-width: 480px;
    padding: 40px 20px;
}

.card {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 32px;
}

.logo {
    font-size: 28px;
    font-weight: 700;
    margin-bottom: 4px;
}

.subtitle {
    color: var(--text-muted);
    font-size: 13px;
    margin-bottom: 24px;
}

h1 { font-size: 20px; font-weight: 700; margin-bottom: 8px; }
h2 { font-size: 16px; font-weight: 600; margin-bottom: 16px; }

.form-group { margin-bottom: 16px; }

.form-group label {
    display: block;
    font-size: 13px;
    color: var(--text-secondary);
    margin-bottom: 6px;
}

input[type="text"],
input[type="email"],
input[type="password"] {
    width: 100%;
    padding: 10px 14px;
    background: #1c1c1c;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    color: var(--text);
    font-size: 14px;
    transition: border-color 0.2s;
}

input:focus {
    outline: none;
    border-color: var(--accent);
}

.btn {
    display: inline-block;
    padding: 10px 24px;
    border: none;
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.2s;
    text-decoration: none;
    text-align: center;
}

.btn-primary {
    background: var(--accent);
    color: #000;
    width: 100%;
}

.btn-primary:hover { background: var(--accent-hover); }
.btn-primary:disabled { opacity: 0.5; cursor: not-allowed; }

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

.btn-secondary:hover { background: var(--card-hover); }

.btn-danger {
    background: #442222;
    border: 1px solid #663333;
    color: var(--error);
}

.link {
    color: var(--accent);
    text-decoration: none;
    font-size: 13px;
}

.link:hover { text-decoration: underline; }

.row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 12px;
}

.mt-16 { margin-top: 16px; }
.mt-24 { margin-top: 24px; }

.alert {
    padding: 12px 16px;
    border-radius: var(--radius-sm);
    font-size: 13px;
    margin-bottom: 16px;
}

.alert-error {
    background: #442222;
    border: 1px solid #663333;
    color: var(--error);
}

.alert-success {
    background: #224422;
    border: 1px solid #336633;
    color: var(--success);
}

.alert-info {
    background: #0f3460;
    border: 1px solid #185FA5;
    color: var(--accent);
}

.code-display {
    font-size: 42px;
    font-weight: 700;
    letter-spacing: 12px;
    color: var(--accent);
    text-align: center;
    padding: 20px;
    background: #1c1c1c;
    border-radius: var(--radius-sm);
    margin: 16px 0;
}

.balance-big {
    font-size: 48px;
    font-weight: 700;
    text-align: center;
    padding: 16px;
}

.balance-label {
    text-align: center;
    color: var(--text-muted);
    font-size: 12px;
}

.package-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
    gap: 12px;
    margin: 16px 0;
}

.package-card {
    background: #1c1c1c;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 16px;
    text-align: center;
    cursor: pointer;
    transition: border-color 0.2s;
}

.package-card:hover { border-color: var(--accent); }
.package-card.selected { border-color: var(--accent); background: #0f3460; }

.package-card .name { font-size: 16px; font-weight: 700; }
.package-card .price { font-size: 18px; color: var(--success); margin: 4px 0; }
.package-card .unit { font-size: 11px; color: var(--text-muted); }

table {
    width: 100%;
    border-collapse: collapse;
    font-size: 13px;
}

th, td {
    padding: 10px 12px;
    text-align: left;
    border-bottom: 1px solid var(--border);
}

th { color: var(--text-muted); font-weight: 600; font-size: 12px; }

.spinner {
    display: inline-block;
    width: 16px;
    height: 16px;
    border: 2px solid var(--border);
    border-top: 2px solid var(--accent);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

@keyframes spin { to { transform: rotate(360deg); } }

.nav { margin-bottom: 24px; }
.nav a { color: var(--text-muted); text-decoration: none; font-size: 13px; }
.nav a:hover { color: var(--text); }
.nav span { color: var(--text-muted); margin: 0 8px; }