:root {
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --secondary: #64748b;
    --success: #10b981;
    --danger: #ef4444;
    --white: #ffffff;
    --bg-light: #f8fafc;
    --text-dark: #1e293b;
    --text-muted: #64748b;
    --border: #e2e8f0;
    --radius: 12px;
    --shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.05), 0 8px 10px -6px rgba(0, 0, 0, 0.05);
}

* { box-sizing: border-box; margin: 0; padding: 0; }
body { font-family: 'Inter', -apple-system, sans-serif; background: var(--bg-light); color: var(--text-dark); }


.navbar { background: var(--white); height: 70px; border-bottom: 1px solid var(--border); display: flex; align-items: center; position: sticky; top: 0; z-index: 100; }
.nav-container { width: 90%; max-width: 1200px; margin: 0 auto; display: flex; justify-content: space-between; align-items: center; }
.logo { font-size: 1.5rem; font-weight: 800; color: var(--text-dark); }
.logo span { color: var(--primary); }
.nav-links { display: flex; list-style: none; gap: 2rem; align-items: center; }
.nav-links a { text-decoration: none; color: var(--text-muted); font-weight: 500; font-size: 0.95rem; transition: 0.2s; cursor: pointer; }
.nav-links a:hover { color: var(--primary); }

.nav-greeting {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-dark);
    margin-right: 0.5rem;
}


.auth-page { background: linear-gradient(135deg, #f0f9ff 0%, #e0f2fe 100%); min-height: 100vh; }
.auth-wrapper { display: flex; justify-content: center; align-items: center; min-height: calc(100vh - 70px); padding: 2rem; }
.auth-card-landscape { background: var(--white); width: 900px; max-width: 100%; border-radius: 20px; overflow: hidden; display: flex; box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.1); border: 1px solid var(--border); }

.auth-brand-side { flex: 1; background: var(--primary); color: var(--white); padding: 3rem; display: flex; flex-direction: column; justify-content: center; position: relative; overflow: hidden; }
.auth-brand-side::before { content: ""; position: absolute; width: 200px; height: 200px; background: rgba(255,255,255,0.1); border-radius: 50%; top: -50px; left: -50px; }
.brand-content { position: relative; z-index: 1; }
.brand-badge { font-size: 3rem; margin-bottom: 1rem; }
.auth-brand-side h2 { font-size: 2rem; margin-bottom: 1rem; }
.auth-brand-side p { line-height: 1.6; opacity: 0.9; }

.auth-form-side { flex: 1.2; padding: 3rem; background: var(--white); }
.auth-tabs { display: flex; border-bottom: 2px solid var(--border); margin-bottom: 2rem; gap: 2rem; }
.tab-btn { background: none; border: none; font-size: 1rem; font-weight: 600; padding: 0.75rem 0; color: var(--text-muted); cursor: pointer; border-bottom: 2px solid transparent; transition: 0.2s; }
.tab-btn.active { color: var(--primary); border-bottom-color: var(--primary); }

.auth-section { display: none; }
.auth-section.active { display: block; animation: slideIn 0.3s ease; }

@keyframes slideIn { from { opacity: 0; transform: translateX(10px); } to { opacity: 1; transform: translateX(0); } }


.admin-toggle-wrapper { display: flex; align-items: center; justify-content: space-between; margin-bottom: 1.5rem; padding: 10px 0; border-top: 1px solid var(--border); }
.admin-toggle-wrapper span { font-size: 0.9rem; font-weight: 600; color: var(--text-dark); }
.switch { position: relative; display: inline-block; width: 50px; height: 26px; }
.switch input { opacity: 0; width: 0; height: 0; }
.slider { position: absolute; cursor: pointer; top: 0; left: 0; right: 0; bottom: 0; background-color: #ccc; transition: .4s; border-radius: 34px; }
.slider:before { position: absolute; content: ""; height: 18px; width: 18px; left: 4px; bottom: 4px; background-color: white; transition: .4s; border-radius: 50%; }
input:checked + .slider { background-color: var(--primary); }
input:checked + .slider:before { transform: translateX(24px); }

.dashboard-page { background: var(--bg-light); }
.dashboard-container { max-width: 1100px; margin: 2rem auto; padding: 0 1rem; }
.page-header { margin-bottom: 2.5rem; border-bottom: 2px solid var(--border); padding-bottom: 1rem; }
.page-header h1 { font-size: 2rem; color: var(--text-dark); margin-bottom: 0.5rem; }
.page-header p { color: var(--text-muted); }

.card { background: var(--white); border-radius: var(--radius); padding: 2rem; box-shadow: var(--shadow); border: 1px solid var(--border); margin-bottom: 1.5rem; transition: transform 0.2s; }
.card:hover { transform: translateY(-3px); }


.input-group { margin-bottom: 1.25rem; }
label { display: block; font-size: 0.85rem; font-weight: 600; margin-bottom: 0.5rem; color: var(--text-dark); }
input, select { width: 100%; padding: 0.8rem 1rem; border: 1.5px solid var(--border); border-radius: 10px; font-size: 0.95rem; transition: 0.2s; }
input:focus, select:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.1); }

.btn-primary { width: 100%; padding: 0.9rem; background: var(--primary); color: var(--white); border: none; border-radius: 10px; font-weight: 600; cursor: pointer; transition: 0.2s; font-size: 1rem; }
.btn-primary:hover { background: var(--primary-dark); transform: scale(1.02); }

.slots-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 1.5rem; }
.slot-card { background: var(--white); border: 1.5px solid var(--border); padding: 1.5rem; border-radius: var(--radius); cursor: pointer; transition: 0.2s; }
.slot-card:hover:not(.booked) { border-color: var(--primary); background: #f0f9ff; }
.slot-card.booked { background: #f1f5f9; cursor: not-allowed; opacity: 0.7; }
.slot-date { font-weight: 700; color: var(--primary); font-size: 0.9rem; margin-bottom: 0.25rem; }
.slot-time { font-size: 1.2rem; font-weight: 800; margin-bottom: 1rem; }

.modal { display: none; position: fixed; inset: 0; background: rgba(0,0,0,0.4); backdrop-filter: blur(4px); z-index: 1000; align-items: center; justify-content: center; }
.modal-content { background: var(--white); width: 500px; max-width: 90%; border-radius: 20px; padding: 2.5rem; position: relative; animation: modalPop 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275); }
.close { position: absolute; top: 1.5rem; right: 1.5rem; font-size: 1.5rem; cursor: pointer; color: var(--text-muted); }

@keyframes modalPop { from { transform: scale(0.9); opacity: 0; } to { transform: scale(1); opacity: 1; } }

.error-msg { color: var(--danger); font-size: 0.85rem; margin-top: 1rem; text-align: center; }
.success-msg { color: var(--success); font-size: 0.85rem; margin-top: 1rem; text-align: center; }
.fade-in { animation: fadeIn 0.8s ease-in-out; }
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }

.admin-actions { display: grid; grid-template-columns: 1fr 1fr; gap: 2rem; }
@media (max-width: 800px) { .admin-actions, .auth-card-landscape { flex-direction: column; grid-template-columns: 1fr; width: 100%; } }