:root {
    --bg-deep: #070b19;
    --bg-card: #0e162d;
    --accent-glow: #00f2fe;
    --accent-secondary: #4facfe;
    --text-main: #f1f5f9;
    --text-muted: #94a3b8;
    --border-color: rgba(0, 242, 254, 0.2);
    --success: #10b981;
    --danger: #ef4444;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: 'Plus Jakarta Sans', sans-serif;
}

body {
    background-color: var(--bg-deep);
    color: var(--text-main);
    min-height: 100vh;
    overflow-x: hidden;
}

.hidden { display: none !important; }
.accent { color: var(--accent-glow); }
.mt-20 { margin-top: 20px; }
.mt-10 { margin-top: 10px; }

/* HEADER & NAVBAR */
header {
    background: rgba(14, 22, 45, 0.9);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 15px 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo-box {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.25rem;
    font-weight: 800;
    color: var(--text-main);
}

.logo-box i {
    color: var(--accent-glow);
    font-size: 1.5rem;
}

.nav-links {
    display: flex;
    gap: 8px;
}

.nav-btn {
    background: transparent;
    border: none;
    color: var(--text-muted);
    padding: 8px 14px;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
    transition: all 0.3s ease;
}

.nav-btn:hover, .nav-btn.active {
    background: linear-gradient(135deg, rgba(0, 242, 254, 0.15), rgba(79, 172, 254, 0.15));
    color: var(--accent-glow);
    border: 1px solid var(--border-color);
}

.user-profile-badge {
    background: rgba(255, 255, 255, 0.05);
    padding: 6px 14px;
    border-radius: 20px;
    font-size: 0.9rem;
    border: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    gap: 10px;
}

.btn-logout {
    background: transparent;
    border: none;
    color: var(--danger);
    cursor: pointer;
    font-size: 1rem;
}

/* SECTION STYLING */
.page-section {
    display: none;
    max-width: 1400px;
    margin: 30px auto;
    padding: 0 30px;
    animation: fadeIn 0.4s ease-in-out;
}

.page-section.active {
    display: block;
}

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

.futuristic-box {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 30px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
}

/* LOGIN SCREEN */
.login-wrapper {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 80vh;
}

.login-card {
    width: 100%;
    max-width: 480px;
}

.brand-header {
    text-align: center;
    margin-bottom: 25px;
}

.brand-header i {
    font-size: 3rem;
    color: var(--accent-glow);
    margin-bottom: 10px;
}

.brand-header h1 {
    font-size: 1.8rem;
    font-weight: 800;
}

.brand-header p {
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-top: 5px;
}

.tab-login-switcher {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
    background: rgba(0, 0, 0, 0.2);
    padding: 5px;
    border-radius: 10px;
}

.tab-sw-btn {
    flex: 1;
    background: transparent;
    border: none;
    color: var(--text-muted);
    padding: 10px;
    font-weight: 600;
    border-radius: 8px;
    cursor: pointer;
    transition: 0.3s;
}

.tab-sw-btn.active {
    background: linear-gradient(135deg, var(--accent-glow), var(--accent-secondary));
    color: var(--bg-deep);
}

.login-form-pane {
    display: none;
}

.login-form-pane.active {
    display: block;
}

.form-group {
    margin-bottom: 15px;
}

.form-group label {
    display: block;
    font-size: 0.9rem;
    margin-bottom: 6px;
    color: var(--text-muted);
}

.form-group input, .form-group textarea, .futuristic-select, .futuristic-input {
    width: 100%;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    padding: 12px 15px;
    border-radius: 10px;
    color: var(--text-main);
    font-size: 1rem;
}

.form-group input:focus, .form-group textarea:focus, .futuristic-select:focus {
    outline: none;
    border-color: var(--accent-glow);
    box-shadow: 0 0 10px rgba(0, 242, 254, 0.3);
}

.password-wrapper {
    position: relative;
}

.toggle-pass {
    position: absolute;
    right: 15px;
    top: 50%;
    transform: translateY(-50%);
    background: transparent;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
}

.btn-primary-futuristic {
    width: 100%;
    background: linear-gradient(135deg, var(--accent-glow), var(--accent-secondary));
    color: var(--bg-deep);
    border: none;
    padding: 14px;
    font-weight: 700;
    border-radius: 10px;
    cursor: pointer;
    transition: 0.3s;
    font-size: 1rem;
    box-shadow: 0 5px 15px rgba(0, 242, 254, 0.3);
}

.btn-primary-futuristic:hover {
    opacity: 0.9;
    transform: translateY(-2px);
}

.btn-secondary-futuristic {
    background: transparent;
    border: 1px solid var(--accent-glow);
    color: var(--accent-glow);
    padding: 12px 24px;
    border-radius: 10px;
    font-weight: 700;
    cursor: pointer;
    transition: 0.3s;
}

.btn-secondary-futuristic:hover {
    background: rgba(0, 242, 254, 0.1);
}

/* HERO BERANDA */
.hero-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    align-items: center;
    padding: 40px 0;
}

.hero-text h2 {
    font-size: 2.5rem;
    font-weight: 800;
    line-height: 1.2;
    margin: 15px 0;
}

.hero-text p {
    color: var(--text-muted);
    font-size: 1.1rem;
    line-height: 1.6;
}

.badge-tag {
    background: rgba(0, 242, 254, 0.1);
    color: var(--accent-glow);
    padding: 6px 14px;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 700;
    border: 1px solid var(--border-color);
}

.hero-info-grid {
    display: flex;
    gap: 15px;
    margin: 25px 0;
}

.info-pill {
    background: rgba(255, 255, 255, 0.05);
    padding: 8px 14px;
    border-radius: 8px;
    font-size: 0.85rem;
    border: 1px solid var(--border-color);
}

.hero-actions {
    display: flex;
    gap: 15px;
}

.hero-visual img {
    width: 100%;
    border-radius: 20px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.6);
}

/* MATERI LAYOUT */
.materi-layout {
    display: grid;
    grid-template-columns: 320px 1fr;
    gap: 30px;
}

.materi-sidebar {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 20px;
    height: fit-content;
}

.materi-sidebar h3 {
    font-size: 1.1rem;
    margin-bottom: 15px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.materi-sidebar ul {
    list-style: none;
}

.sub-nav-item {
    padding: 12px 15px;
    border-radius: 10px;
    cursor: pointer;
    font-size: 0.95rem;
    color: var(--text-muted);
    margin-bottom: 8px;
    transition: 0.3s;
}

.sub-nav-item:hover, .sub-nav-item.active {
    background: linear-gradient(135deg, rgba(0, 242, 254, 0.15), rgba(79, 172, 254, 0.15));
    color: var(--accent-glow);
    border-left: 4px solid var(--accent-glow);
}

.progress-box {
    margin-top: 25px;
    background: rgba(0, 0, 0, 0.2);
    padding: 15px;
    border-radius: 10px;
    font-size: 0.85rem;
}

.progress-bar-container {
    width: 100%;
    height: 8px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 4px;
    margin: 8px 0;
    overflow: hidden;
}

#materi-progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--accent-glow), var(--accent-secondary));
    transition: width 0.4s ease;
}

.materi-pane {
    display: none;
}

.materi-pane.active {
    display: block;
}

.materi-pane h2 {
    font-size: 1.8rem;
    margin-bottom: 15px;
}

.lead-text {
    font-size: 1.1rem;
    color: var(--text-muted);
    margin-bottom: 25px;
    line-height: 1.6;
}

.content-grid-2 {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin-bottom: 25px;
}

.card-highlight {
    background: rgba(0, 242, 254, 0.05);
    border: 1px solid var(--border-color);
    padding: 20px;
    border-radius: 12px;
}

.image-showcase {
    margin: 25px 0;
    text-align: center;
}

.image-showcase img {
    max-width: 100%;
    max-height: 350px;
    border-radius: 12px;
    border: 1px solid var(--border-color);
}

.caption {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-top: 8px;
}

.materi-footer-nav {
    display: flex;
    justify-content: space-between;
    margin-top: 30px;
    padding-top: 20px;
    border-top: 1px solid var(--border-color);
}

.btn-sec {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    color: var(--text-main);
    padding: 10px 20px;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
}

/* TABEL FUTURISTIK */
.table-responsive {
    overflow-x: auto;
    margin: 20px 0;
}

.futuristic-table {
    width: 100%;
    border-collapse: collapse;
    text-align: left;
    font-size: 0.95rem;
}

.futuristic-table th, .futuristic-table td {
    padding: 14px 18px;
    border-bottom: 1px solid var(--border-color);
}

.futuristic-table th {
    background: rgba(0, 242, 254, 0.1);
    color: var(--accent-glow);
    font-weight: 700;
}

/* SIMULASI INTERAKTIF */
.sim-tabs-container {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
    flex-wrap: wrap;
}

.sim-tab-btn {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    color: var(--text-muted);
    padding: 12px 20px;
    border-radius: 10px;
    cursor: pointer;
    font-weight: 600;
    transition: 0.3s;
}

.sim-tab-btn.active, .sim-tab-btn:hover {
    background: linear-gradient(135deg, rgba(0, 242, 254, 0.2), rgba(79, 172, 254, 0.2));
    color: var(--accent-glow);
    border-color: var(--accent-glow);
}

.sim-pane {
    display: none;
}

.sim-pane.active {
    display: block;
}

.sim1-interactive-area {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin-top: 20px;
}

.sim1-pool, .dropzone {
    background: rgba(0, 0, 0, 0.3);
    padding: 20px;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    min-height: 200px;
}

.draggable-item {
    background: linear-gradient(135deg, var(--accent-glow), var(--accent-secondary));
    color: var(--bg-deep);
    padding: 10px 15px;
    border-radius: 8px;
    margin-bottom: 10px;
    font-weight: 600;
    cursor: grab;
}

.drop-target-box {
    margin-top: 10px;
    min-height: 120px;
}

.feedback-msg {
    margin-top: 15px;
    font-weight: 600;
    font-size: 1rem;
}

/* KURVA SIGMOID SIMULASI */
.sigmoid-interactive-box {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin-top: 20px;
    align-items: center;
}

.curve-visual-box {
    background: rgba(0,0,0,0.4);
    height: 250px;
    border-radius: 12px;
    position: relative;
    border: 1px solid var(--border-color);
}

.curve-node {
    position: absolute;
    background: var(--accent-glow);
    color: var(--bg-deep);
    border: none;
    padding: 6px 12px;
    border-radius: 20px;
    font-weight: 700;
    cursor: pointer;
    box-shadow: 0 0 10px var(--accent-glow);
}

.sim2-options {
    display: flex;
    gap: 10px;
    margin-top: 15px;
}

/* SEQUENCE PUZZLE */
.sequence-puzzle-box {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-top: 20px;
}

.sequence-card-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: rgba(255,255,255,0.03);
    padding: 12px 18px;
    border-radius: 10px;
    border: 1px solid var(--border-color);
}

/* EVALUASI & REFLEKSI */
.eval-question-card {
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid var(--border-color);
    padding: 20px;
    border-radius: 12px;
    margin-bottom: 20px;
}

.eval-question-card h4 {
    color: var(--accent-glow);
    margin-bottom: 8px;
}

.eval-question-card label {
    display: inline-block;
    margin-top: 8px;
    cursor: pointer;
    color: var(--text-muted);
}

.score-card-banner {
    background: linear-gradient(135deg, rgba(0, 242, 254, 0.15), rgba(79, 172, 254, 0.15));
    border: 1px solid var(--accent-glow);
    padding: 25px;
    border-radius: 12px;
    text-align: center;
    margin: 20px 0;
}

.score-card-banner h3 {
    font-size: 2rem;
    color: var(--accent-glow);
}

/* DASHBOARD GURU */
.dashboard-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.dash-actions {
    display: flex;
    gap: 10px;
}

.filter-bar {
    display: flex;
    gap: 15px;
}

.modal-backdrop {
    position: fixed;
    top: 0; left: 0; width: 100%; height: 100%;
    background: rgba(0,0,0,0.8);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 2000;
}

.modal-box {
    width: 90%;
    max-width: 600px;
    max-height: 80vh;
    overflow-y: auto;
}