/* ==========================================
   INSTRUCTOR PORTAL - PREMIUM STYLING
   ========================================== */

:root {
    --ip-primary: #667eea;
    --ip-primary-dark: #5a6fd6;
    --ip-primary-light: rgba(102, 126, 234, 0.1);
    --ip-success: #10b981;
    --ip-success-light: rgba(16, 185, 129, 0.1);
    --ip-warning: #f59e0b;
    --ip-warning-light: rgba(245, 158, 11, 0.1);
    --ip-danger: #ef4444;
    --ip-info: #3b82f6;
    --ip-info-light: rgba(59, 130, 246, 0.1);
    --ip-bg: #f4f7fa;
    --ip-surface: #ffffff;
    --ip-border: #e2e8f0;
    --ip-text: #1f2937;
    --ip-text-secondary: #6b7280;
    --ip-text-muted: #9ca3af;
    --ip-radius: 12px;
    --ip-radius-sm: 8px;
    --ip-shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
    --ip-shadow-hover: 0 8px 30px rgba(0, 0, 0, 0.1);
    --ip-transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
    background: var(--ip-bg);
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    color: var(--ip-text);
    min-height: 100vh;
}

/* ---- Header ---- */
.ip-header {
    background: var(--ip-surface);
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.04);
    position: sticky;
    top: 0;
    z-index: 100;
}

.ip-header-left {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.ip-logo {
    width: 44px;
    height: 44px;
    background: linear-gradient(135deg, var(--ip-primary), #764ba2);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.25rem;
}

.ip-header-left h1 {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--ip-text);
}

.ip-subtitle {
    font-size: 0.85rem;
    color: var(--ip-text-secondary);
}

.ip-header-right {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.ip-date-display {
    font-size: 0.9rem;
    color: var(--ip-text-secondary);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.ip-btn-icon {
    width: 40px;
    height: 40px;
    border: none;
    background: var(--ip-bg);
    border-radius: 10px;
    cursor: pointer;
    color: var(--ip-text-secondary);
    font-size: 1rem;
    transition: var(--ip-transition);
}

.ip-btn-icon:hover {
    background: var(--ip-danger);
    color: white;
}

/* ---- Main ---- */
.ip-main {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1.5rem 2rem 3rem;
}

/* ---- KPI Grid ---- */
.ip-kpi-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.ip-kpi-card {
    background: var(--ip-surface);
    border-radius: var(--ip-radius);
    padding: 1.25rem;
    display: flex;
    align-items: center;
    gap: 1rem;
    box-shadow: var(--ip-shadow);
    transition: var(--ip-transition);
    border-left: 4px solid transparent;
}

.ip-kpi-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--ip-shadow-hover);
}

.ip-kpi-primary { border-left-color: var(--ip-primary); }
.ip-kpi-success { border-left-color: var(--ip-success); }
.ip-kpi-warning { border-left-color: var(--ip-warning); }
.ip-kpi-info { border-left-color: var(--ip-info); }

.ip-kpi-icon {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
}

.ip-kpi-primary .ip-kpi-icon { background: var(--ip-primary-light); color: var(--ip-primary); }
.ip-kpi-success .ip-kpi-icon { background: var(--ip-success-light); color: var(--ip-success); }
.ip-kpi-warning .ip-kpi-icon { background: var(--ip-warning-light); color: var(--ip-warning); }
.ip-kpi-info .ip-kpi-icon { background: var(--ip-info-light); color: var(--ip-info); }

.ip-kpi-value {
    font-size: 1.75rem;
    font-weight: 800;
    color: var(--ip-text);
    line-height: 1;
}

.ip-kpi-label {
    font-size: 0.8rem;
    color: var(--ip-text-secondary);
    margin-top: 2px;
}

/* ---- Tabs ---- */
.ip-tabs {
    display: flex;
    gap: 0.25rem;
    background: var(--ip-surface);
    border-radius: var(--ip-radius);
    padding: 0.5rem;
    margin-bottom: 1.5rem;
    box-shadow: var(--ip-shadow);
    overflow-x: auto;
}

.ip-tab {
    flex: 1;
    min-width: 120px;
    padding: 0.75rem 1rem;
    border: none;
    background: transparent;
    border-radius: var(--ip-radius-sm);
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--ip-text-secondary);
    transition: var(--ip-transition);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    white-space: nowrap;
}

.ip-tab:hover {
    background: var(--ip-bg);
    color: var(--ip-text);
}

.ip-tab.active {
    background: var(--ip-primary);
    color: white;
    font-weight: 600;
}

.ip-tab-content {
    display: none;
}

.ip-tab-content.active {
    display: block;
    animation: ipFadeIn 0.3s ease;
}

@keyframes ipFadeIn {
    from { opacity: 0; transform: translateY(8px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ---- Cards ---- */
.ip-card {
    background: var(--ip-surface);
    border-radius: var(--ip-radius);
    box-shadow: var(--ip-shadow);
    overflow: hidden;
}

.ip-card-header {
    padding: 1rem 1.5rem;
    border-bottom: 1px solid var(--ip-border);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.ip-card-header h3 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--ip-text);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.ip-card-header h3 i {
    color: var(--ip-primary);
}

.ip-card-body {
    padding: 1.5rem;
}

.ip-dashboard-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
}

@media (max-width: 900px) {
    .ip-dashboard-grid { grid-template-columns: 1fr; }
}

/* ---- Classes List ---- */
.ip-classes-list {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    max-height: 500px;
    overflow-y: auto;
}

.ip-class-card {
    background: var(--ip-bg);
    border-radius: var(--ip-radius-sm);
    padding: 1rem 1.25rem;
    cursor: pointer;
    transition: var(--ip-transition);
    border-left: 4px solid var(--ip-primary);
    display: flex;
    gap: 1rem;
    align-items: center;
}

.ip-class-card:hover {
    background: var(--ip-primary-light);
    transform: translateX(4px);
}

.ip-class-card.status-IN_PROGRESS { border-left-color: var(--ip-success); }
.ip-class-card.status-COMPLETED { border-left-color: var(--ip-text-muted); }
.ip-class-card.status-CANCELLED { border-left-color: var(--ip-danger); }

.ip-class-time {
    min-width: 70px;
    text-align: center;
}

.ip-class-time .time {
    font-size: 1rem;
    font-weight: 700;
    color: var(--ip-text);
}

.ip-class-time .date {
    font-size: 0.75rem;
    color: var(--ip-text-secondary);
}

.ip-class-info {
    flex: 1;
}

.ip-class-info h4 {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--ip-text);
    margin-bottom: 0.25rem;
}

.ip-class-info .meta {
    font-size: 0.8rem;
    color: var(--ip-text-secondary);
    display: flex;
    gap: 1rem;
}

.ip-class-badge {
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
}

.badge-SCHEDULED { background: var(--ip-warning-light); color: var(--ip-warning); }
.badge-IN_PROGRESS { background: var(--ip-success-light); color: var(--ip-success); }
.badge-COMPLETED { background: var(--ip-bg); color: var(--ip-text-muted); }
.badge-CANCELLED { background: rgba(239, 68, 68, 0.1); color: var(--ip-danger); }

/* ---- Next Class Card ---- */
.ip-card-next-class {
    border-top: 4px solid var(--ip-primary);
}

.ip-next-class-info {
    text-align: center;
    padding: 1rem 0;
}

.ip-next-class-info .time {
    font-size: 2rem;
    font-weight: 800;
    color: var(--ip-primary);
}

.ip-next-class-info .title {
    font-size: 1.1rem;
    font-weight: 600;
    margin: 0.5rem 0;
}

.ip-next-class-info .detail {
    font-size: 0.9rem;
    color: var(--ip-text-secondary);
}

/* ---- Students Grid ---- */
.ip-students-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1rem;
}

.ip-student-card {
    background: var(--ip-bg);
    border-radius: var(--ip-radius-sm);
    padding: 1rem;
    display: flex;
    align-items: center;
    gap: 1rem;
    transition: var(--ip-transition);
}

.ip-student-card:hover {
    background: var(--ip-primary-light);
}

.ip-student-avatar {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    object-fit: cover;
    background: var(--ip-border);
}

.ip-student-info h4 {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--ip-text);
}

.ip-student-info .detail {
    font-size: 0.8rem;
    color: var(--ip-text-secondary);
}

.ip-student-stats {
    display: flex;
    gap: 0.75rem;
    margin-top: 0.5rem;
}

.ip-student-stat {
    font-size: 0.75rem;
    color: var(--ip-text-secondary);
    display: flex;
    align-items: center;
    gap: 0.25rem;
}

.ip-student-stat i { font-size: 0.7rem; }

/* ---- Schedule Grid ---- */
.ip-schedule-grid {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    gap: 0.5rem;
    min-height: 400px;
}

.ip-schedule-day {
    background: var(--ip-bg);
    border-radius: var(--ip-radius-sm);
    padding: 0.75rem;
    min-height: 120px;
}

.ip-schedule-day-header {
    font-size: 0.8rem;
    font-weight: 700;
    color: var(--ip-text-secondary);
    text-transform: uppercase;
    text-align: center;
    padding-bottom: 0.5rem;
    border-bottom: 1px solid var(--ip-border);
    margin-bottom: 0.5rem;
}

.ip-schedule-day.today .ip-schedule-day-header {
    color: var(--ip-primary);
    border-bottom-color: var(--ip-primary);
}

.ip-schedule-class {
    background: var(--ip-surface);
    border-radius: 6px;
    padding: 0.5rem;
    margin-bottom: 0.5rem;
    font-size: 0.75rem;
    border-left: 3px solid var(--ip-primary);
    cursor: pointer;
    transition: var(--ip-transition);
}

.ip-schedule-class:hover {
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.ip-schedule-class .sc-time {
    font-weight: 700;
    color: var(--ip-text);
}

.ip-schedule-class .sc-name {
    color: var(--ip-text-secondary);
    margin-top: 2px;
}

@media (max-width: 900px) {
    .ip-schedule-grid {
        grid-template-columns: 1fr;
    }
    .ip-schedule-day {
        min-height: auto;
    }
}

/* ---- Financial Summary ---- */
.ip-financial-summary {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 1rem;
}

.ip-financial-item {
    background: var(--ip-bg);
    border-radius: var(--ip-radius-sm);
    padding: 1.25rem;
    text-align: center;
}

.ip-financial-item .value {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--ip-text);
}

.ip-financial-item .label {
    font-size: 0.8rem;
    color: var(--ip-text-secondary);
    margin-top: 0.25rem;
}

/* ---- Lesson Plan ---- */
.ip-lesson-timeline {
    position: relative;
    padding-left: 2.5rem;
}

.ip-lesson-timeline::before {
    content: '';
    position: absolute;
    left: 0.75rem;
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--ip-border);
}

.ip-lesson-item {
    position: relative;
    padding: 0.75rem 0;
    border-bottom: 1px solid var(--ip-border);
}

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

.ip-lesson-number {
    position: absolute;
    left: -2.25rem;
    width: 1.75rem;
    height: 1.75rem;
    background: var(--ip-primary);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.75rem;
    font-weight: 700;
}

.ip-lesson-item h4 {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--ip-text);
}

.ip-lesson-item .meta {
    font-size: 0.8rem;
    color: var(--ip-text-secondary);
    display: flex;
    gap: 1rem;
    margin-top: 0.25rem;
}

/* ---- Search ---- */
.ip-search-box {
    position: relative;
}

.ip-search-box i {
    position: absolute;
    left: 0.75rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--ip-text-muted);
    font-size: 0.85rem;
}

.ip-search-input {
    padding: 0.5rem 0.75rem 0.5rem 2.25rem;
    border: 1px solid var(--ip-border);
    border-radius: 8px;
    font-size: 0.85rem;
    width: 250px;
    transition: var(--ip-transition);
}

.ip-search-input:focus {
    outline: none;
    border-color: var(--ip-primary);
    box-shadow: 0 0 0 3px var(--ip-primary-light);
}

/* ---- Date Input ---- */
.ip-date-input {
    padding: 0.4rem 0.6rem;
    border: 1px solid var(--ip-border);
    border-radius: 6px;
    font-size: 0.85rem;
    color: var(--ip-text);
}

/* ---- Modal ---- */
.ip-modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    display: none;
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

.ip-modal {
    background: var(--ip-surface);
    border-radius: var(--ip-radius);
    width: 90%;
    max-width: 800px;
    max-height: 85vh;
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

.ip-modal-header {
    padding: 1.25rem 1.5rem;
    border-bottom: 1px solid var(--ip-border);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.ip-modal-header h2 {
    font-size: 1.15rem;
    font-weight: 700;
}

.ip-modal-close {
    border: none;
    background: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--ip-text-secondary);
    width: 36px;
    height: 36px;
    border-radius: 8px;
    transition: var(--ip-transition);
}

.ip-modal-close:hover {
    background: var(--ip-bg);
    color: var(--ip-text);
}

.ip-modal-body {
    padding: 1.5rem;
    overflow-y: auto;
    flex: 1;
}

.ip-modal-footer {
    padding: 1rem 1.5rem;
    border-top: 1px solid var(--ip-border);
    text-align: right;
}

.ip-modal-students {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.ip-modal-student {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.75rem;
    background: var(--ip-bg);
    border-radius: var(--ip-radius-sm);
}

.ip-modal-student-info {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.ip-modal-student-avatar {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    object-fit: cover;
}

/* ---- Buttons ---- */
.ip-btn {
    padding: 0.6rem 1.25rem;
    border: none;
    border-radius: 8px;
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--ip-transition);
}

.ip-btn-primary {
    background: var(--ip-primary);
    color: white;
}

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

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

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

/* ---- Empty / Loading States ---- */
.ip-loading {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 3rem;
}

.ip-spinner {
    width: 36px;
    height: 36px;
    border: 3px solid var(--ip-border);
    border-top-color: var(--ip-primary);
    border-radius: 50%;
    animation: ipSpin 0.8s linear infinite;
}

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

.ip-empty-state {
    text-align: center;
    padding: 3rem;
    color: var(--ip-text-muted);
}

.ip-empty-state i {
    font-size: 3rem;
    margin-bottom: 1rem;
    display: block;
}

.ip-empty-state p {
    font-size: 1rem;
}

/* ---- Check-in Toggle ---- */
.ip-checkin-toggle {
    position: relative;
    width: 44px;
    height: 24px;
    cursor: pointer;
}

.ip-checkin-toggle input {
    opacity: 0;
    width: 0;
    height: 0;
}

.ip-checkin-slider {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--ip-border);
    border-radius: 12px;
    transition: var(--ip-transition);
}

.ip-checkin-slider::before {
    content: '';
    position: absolute;
    width: 18px;
    height: 18px;
    left: 3px;
    bottom: 3px;
    background: white;
    border-radius: 50%;
    transition: var(--ip-transition);
}

.ip-checkin-toggle input:checked + .ip-checkin-slider {
    background: var(--ip-success);
}

.ip-checkin-toggle input:checked + .ip-checkin-slider::before {
    transform: translateX(20px);
}

/* ---- Responsive ---- */
@media (max-width: 768px) {
    .ip-header { padding: 0.75rem 1rem; }
    .ip-main { padding: 1rem; }
    .ip-kpi-grid { grid-template-columns: repeat(2, 1fr); }
    .ip-tabs { flex-wrap: nowrap; overflow-x: auto; }
    .ip-tab { min-width: 100px; font-size: 0.8rem; padding: 0.6rem 0.75rem; }
    .ip-tab i { display: none; }
    .ip-students-grid { grid-template-columns: 1fr; }
    .ip-search-input { width: 100%; }
}