* { box-sizing: border-box; font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; margin: 0; padding: 0; }
body { background: #f0f2f5; color: #1a1a1a; line-height: 1.5; }

.center-body { display: flex; justify-content: center; align-items: center; min-height: 100vh; padding: 15px; }
.login-card { background: white; padding: 30px; border-radius: 12px; box-shadow: 0 4px 20px rgba(0,0,0,0.1); width: 100%; max-width: 600px; text-align: center; }

/* Logotipo y Títulos */
.logo { max-width: 140px; height: auto; display: block; margin: 10px auto 15px auto; }
.dojo-welcome { font-size: 20px; color: #0f172a; font-weight: bold; margin-bottom: 5px; }
.portal-subtitle { font-size: 16px; color: #475569; margin-bottom: 20px; border-bottom: 2px solid #e2e8f0; padding-bottom: 10px; }

.forms-container { display: flex; gap: 20px; text-align: left; }
.form-box { flex: 1; display: flex; flex-direction: column; gap: 12px; background: #f8fafc; padding: 15px; border-radius: 8px; border: 1px solid #e2e8f0; }
.form-box input { padding: 12px; border: 1px solid #cbd5e1; border-radius: 6px; font-size: 15px; }
.form-box button { padding: 12px; background: #2563eb; color: white; border: none; border-radius: 6px; cursor: pointer; font-weight: bold; font-size: 15px; }

/* Header */
.header { background: #0f172a; color: white; padding: 15px 25px; display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 15px; }
.header-info { text-align: right; }
.header-welcome { font-size: 13px; color: #94a3b8; text-transform: uppercase; letter-spacing: 0.5px; margin-bottom: 2px; }
.btn-logout { background: #ef4444; color: white; text-decoration: none; padding: 8px 16px; border-radius: 6px; font-weight: bold; }

.container { padding: 15px; max-width: 1200px; margin: auto; }
.alert-success { background: #dcfce7; color: #166534; padding: 12px; border-radius: 6px; border: 1px solid #86efac; margin-bottom: 15px; font-weight: bold; text-align: center; }

.tabs { display: flex; gap: 10px; margin-bottom: 20px; }
.tab-btn { flex: 1; padding: 12px; border: none; background: #e2e8f0; cursor: pointer; border-radius: 6px; font-weight: bold; }
.tab-btn.active { background: #2563eb; color: white; }
.tab-content { display: none; }
.tab-content.active { display: block; }

/* Calendario */
.calendar-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 15px; }
.month-card { background: white; padding: 15px; border-radius: 8px; box-shadow: 0 2px 8px rgba(0,0,0,0.05); }
.month-card h4 { margin-bottom: 10px; text-align: center; color: #1e293b; border-bottom: 2px solid #e2e8f0; padding-bottom: 5px; }
.days-header { display: grid; grid-template-columns: repeat(7, 1fr); text-align: center; font-size: 11px; font-weight: bold; color: #64748b; margin-bottom: 5px; }
.days-grid { display: grid; grid-template-columns: repeat(7, 1fr); gap: 4px; }
.day-label { position: relative; width: 100%; aspect-ratio: 1; display: flex; align-items: center; justify-content: center; font-size: 13px; border-radius: 4px; border: 1px solid #e2e8f0; background: #fff; cursor: pointer; user-select: none; }
.day-label.disabled { background: #f1f5f9; color: #cbd5e1; cursor: not-allowed; border-color: #f1f5f9; }
.day-label input { display: none; }
.day-label.selected { background: #22c55e; color: white; border-color: #16a34a; font-weight: bold; }

.btn-save-container { position: sticky; bottom: 15px; background: white; padding: 15px; border-radius: 8px; box-shadow: 0 -2px 10px rgba(0,0,0,0.1); text-align: center; margin-top: 20px; z-index: 100; }
.btn-save { background: #16a34a; color: white; border: none; padding: 14px 30px; font-size: 16px; font-weight: bold; border-radius: 6px; cursor: pointer; width: 100%; max-width: 400px; }

.summary-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 10px; margin-top: 15px; }
.stat-box { background: white; padding: 12px; border-left: 4px solid #2563eb; border-radius: 4px; font-size: 15px; }

/* Pagos */
.payments-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 15px; }
.payment-card { padding: 20px; text-align: center; border-radius: 8px; color: white; }
.payment-card.paid { background: #16a34a; }
.payment-card.unpaid { background: #dc2626; }

/* Instructor Layout */
.instructor-layout { display: flex; gap: 20px; }
.sidebar { width: 320px; background: white; padding: 15px; border-radius: 8px; flex-shrink: 0; }
.main-content { flex: 1; background: white; padding: 20px; border-radius: 8px; }

.student-select { width: 100%; padding: 10px; border: 1px solid #cbd5e1; border-radius: 6px; font-size: 15px; background: #f8fafc; margin-top: 5px; }

.add-form { display: flex; flex-direction: column; gap: 10px; }
.add-form input { padding: 10px; border: 1px solid #cbd5e1; border-radius: 4px; }
.add-form button { padding: 10px; background: #16a34a; color: white; border: none; border-radius: 4px; font-weight: bold; cursor: pointer; }

.actions-bar { display: flex; justify-content: space-between; align-items: center; margin-bottom: 15px; flex-wrap: wrap; gap: 10px; }
.btn-download { background: #2563eb; color: white; text-decoration: none; padding: 10px 15px; border-radius: 6px; font-weight: bold; display: inline-block; text-align: center; }

.payments-admin-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 10px; margin-top: 10px; }
.payment-admin-box { border: 1px solid #e2e8f0; padding: 10px; border-radius: 6px; display: flex; flex-direction: column; gap: 8px; text-align: center; }
.btn-status { border: none; padding: 8px; border-radius: 4px; font-weight: bold; cursor: pointer; color: white; width: 100%; }
.btn-status.paid { background: #22c55e; }
.btn-status.unpaid { background: #ef4444; }

.delete-section { margin-top: 40px; padding-top: 20px; border-top: 2px dashed #fca5a5; text-align: right; }
.btn-delete { background: #dc2626; color: white; text-decoration: none; padding: 10px 18px; border-radius: 6px; font-weight: bold; display: inline-block; }

.error { color: #dc2626; text-align: center; margin-bottom: 10px; font-weight: bold; }

/* Celulares */
@media (max-width: 768px) {
    .forms-container { flex-direction: column; }
    .instructor-layout { flex-direction: column; }
    .sidebar { width: 100%; }
    .header { text-align: center; flex-direction: column; }
    .header-info { text-align: center; }
    .btn-save { width: 100%; }
    .delete-section { text-align: center; }
}