:root {
    --bg-dark: #0A192F;
    --card-bg: #112240;
    --text-primary: #F8FAFC;
    --text-secondary: #94A3B8;
    --accent-green: #10B981;
    --accent-cyan: #06B6D4;
    --accent-gold: #F59E0B;
    --accent-red: #EF4444;
    --border-color: #233554;
    --font-main: 'Plus Jakarta Sans', sans-serif;
}

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

body {
    background-color: var(--bg-dark);
    color: var(--text-primary);
    font-family: var(--font-main);
    line-height: 1.6;
    min-height: 100vh;
}

/* NAVBAR */
.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 2rem;
    background: rgba(10, 25, 47, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 100;
}

.logo {
    font-size: 1.4rem;
    font-weight: 800;
    color: var(--accent-cyan);
}

.logo .badge {
    background: var(--accent-green);
    color: #000;
    font-size: 0.8rem;
    padding: 2px 6px;
    border-radius: 4px;
}

.nav-links {
    display: flex;
    gap: 10px;
}

.nav-links button {
    background: transparent;
    border: none;
    color: var(--text-secondary);
    font-weight: 600;
    padding: 8px 14px;
    cursor: pointer;
    border-radius: 6px;
    transition: all 0.3s ease;
}

.nav-links button:hover {
    color: var(--accent-cyan);
    background: rgba(6, 182, 212, 0.1);
}

/* PROGRESS BAR */
.progress-container {
    width: 100%;
    height: 4px;
    background: var(--border-color);
}

.progress-bar {
    height: 100%;
    width: 0%;
    background: linear-gradient(90deg, var(--accent-cyan), var(--accent-green));
    transition: width 0.4s ease;
}

/* LAYOUT */
.app-container {
    max-width: 1200px;
    margin: 2rem auto;
    padding: 0 1rem;
}

.hidden-section {
    display: none !important;
}

.active-section {
    display: block;
}

/* HERO BERANDA */
.hero {
    background: radial-gradient(circle at top right, rgba(6, 182, 212, 0.15), transparent 60%), var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 3rem;
    margin-top: 1rem;
}

.hero-tag {
    color: var(--accent-gold);
    font-size: 0.9rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.hero h1 {
    font-size: 2.5rem;
    margin: 1rem 0;
    color: #fff;
}

.subtitle {
    color: var(--text-secondary);
    font-size: 1.1rem;
    max-width: 800px;
    margin-bottom: 2rem;
}

.info-card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.info-card {
    display: flex;
    gap: 1rem;
    background: rgba(255, 255, 255, 0.03);
    padding: 1.2rem;
    border-radius: 12px;
    border: 1px solid var(--border-color);
}

.info-card .icon {
    font-size: 2rem;
}

/* BUTTONS */
.btn-primary, .btn-login {
    background: linear-gradient(135deg, var(--accent-green), #059669);
    color: #fff;
    border: none;
    padding: 12px 24px;
    border-radius: 8px;
    font-weight: 700;
    cursor: pointer;
    transition: transform 0.2s ease;
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    padding: 12px 24px;
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
}

.btn-primary:hover, .btn-secondary:hover, .btn-login:hover {
    transform: translateY(-2px);
}

/* MATERI SIDEBAR LAYOUT */
.layout-with-sidebar {
    display: grid;
    grid-template-columns: 280px 1fr;
    gap: 2rem;
}

.sidebar {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 1.5rem;
    height: fit-content;
}

.sidebar ul {
    list-style: none;
    margin-top: 1rem;
}

.sidebar li {
    padding: 10px 12px;
    margin-bottom: 6px;
    border-radius: 6px;
    color: var(--text-secondary);
    cursor: pointer;
}

.sidebar li.active, .sidebar li:hover {
    background: rgba(6, 182, 212, 0.15);
    color: var(--accent-cyan);
    font-weight: 700;
}

.content-body {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 2rem;
}

/* FLOW DIAGRAM & FORMULA */
.flow-diagram {
    display: flex;
    flex-direction: column;
    gap: 10px;
    margin: 1.5rem 0;
}

.flow-box {
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid var(--border-color);
    padding: 12px 18px;
    border-radius: 8px;
}

.flow-box.highlight {
    border-color: var(--accent-green);
    background: rgba(16, 185, 129, 0.1);
}

.flow-arrow {
    color: var(--accent-gold);
    font-size: 0.85rem;
    padding-left: 10px;
}

.formula-card {
    background: #0d1117;
    border-left: 4px solid var(--accent-cyan);
    padding: 1rem;
    margin: 1rem 0;
    font-size: 1.1rem;
}

/* CARDS & SIMULASI */
.grid-2 {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 1.5rem;
}

.margin-top {
    margin-top: 1.5rem;
}

.sim-card, .case-card, .quiz-card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 1.5rem;
    margin-bottom: 1rem;
}

.drag-container {
    display: flex;
    gap: 1rem;
    margin: 1rem 0;
}

.drag-items, .drop-zone {
    flex: 1;
    min-height: 120px;
    background: rgba(0, 0, 0, 0.2);
    border: 1px dashed var(--border-color);
    padding: 10px;
    border-radius: 8px;
}

.drag-item {
    background: var(--accent-cyan);
    color: #000;
    font-weight: 700;
    padding: 8px;
    border-radius: 6px;
    margin-bottom: 8px;
    cursor: grab;
}

.feedback {
    margin-top: 10px;
    padding: 10px;
    border-radius: 6px;
    font-weight: 600;
}

.feedback.correct {
    background: rgba(16, 185, 129, 0.2);
    color: var(--accent-green);
}

.feedback.wrong {
    background: rgba(239, 68, 68, 0.2);
    color: var(--accent-red);
}

.table-sim, .data-table, .dash-table {
    width: 100%;
    border-collapse: collapse;
    margin: 1rem 0;
}

.table-sim th, .table-sim td, .data-table td, .dash-table th, .dash-table td {
    border: 1px solid var(--border-color);
    padding: 10px;
    text-align: left;
}

.form-group {
    margin-bottom: 1.2rem;
}

.form-group label {
    display: block;
    margin-bottom: 6px;
    font-weight: 600;
}

.form-group input, .form-group textarea {
    width: 100%;
    padding: 10px;
    border-radius: 6px;
    border: 1px solid var(--border-color);
    background: #0d1117;
    color: #fff;
}

/* ==========================================================================
   DESAIN POPUP LOGIN TERHUBUNG SESUAI GAMBAR DENGAN 2 SISI (SPLIT CARD)
   ========================================================================== */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.75);
    justify-content: center;
    align-items: center;
    z-index: 1000;
    backdrop-filter: blur(4px);
}

.login-card {
    position: relative;
    display: flex;
    width: 800px;
    max-width: 92vw;
    height: 450px;
    max-height: 90vh;
    background: #FFFFFF;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 20px 40px rgba(0,0,0,0.5);
}

.close-btn {
    position: absolute;
    top: 12px;
    right: 18px;
    font-size: 26px;
    color: #FFFFFF;
    cursor: pointer;
    z-index: 10;
    font-weight: bold;
}

/* SISI KIRI (ILUSTRASI HANDPHONE & PESAWAT) */
.login-left {
    flex: 1;
    background-color: #F7FAFC;
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.illustration-container {
    position: relative;
    width: 220px;
    height: 300px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.phone-mockup {
    width: 150px;
    height: 270px;
    background: #2D3748;
    border-radius: 28px;
    padding: 10px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.15);
    position: relative;
}

.phone-notch {
    width: 50px;
    height: 8px;
    background: #1A202C;
    margin: 0 auto 10px auto;
    border-radius: 4px;
}

.phone-screen {
    width: 100%;
    height: 220px;
    background: #EBF8FF;
    border-radius: 18px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.lock-graphic {
    width: 60px;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.lock-shackle {
    width: 32px;
    height: 28px;
    border: 6px solid #4A5568;
    border-bottom: none;
    border-top-left-radius: 16px;
    border-top-right-radius: 16px;
}

.lock-body {
    width: 54px;
    height: 44px;
    background: #ECC94B;
    border-radius: 8px;
    display: flex;
    justify-content: center;
    align-items: center;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.lock-keyhole {
    width: 8px;
    height: 12px;
    background: #2D3748;
    border-radius: 4px;
}

.flight-line {
    position: absolute;
    top: 20px;
    left: 40px;
    width: 160px;
    height: 70px;
    z-index: 2;
    overflow: visible;
}

.paper-plane-icon {
    position: absolute;
    top: 15px;
    right: 10px;
    font-size: 26px;
    transform: rotate(15deg);
    z-index: 3;
}

/* SISI KANAN (FORM BLUE PANEL) */
.login-right {
    flex: 1.1;
    background-color: #1C82FF;
    padding: 40px 40px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    color: #FFFFFF;
}

.welcome-title {
    font-size: 1.8rem;
    font-weight: 800;
    letter-spacing: 2px;
    margin-bottom: 15px;
    text-transform: uppercase;
}

.role-selector {
    display: flex;
    gap: 10px;
    margin-bottom: 25px;
}

.role-btn {
    background: rgba(255, 255, 255, 0.2);
    border: none;
    color: #FFFFFF;
    padding: 6px 16px;
    border-radius: 20px;
    cursor: pointer;
    font-weight: 600;
    font-size: 0.85rem;
    transition: all 0.2s ease;
}

.role-btn.active, .role-btn:hover {
    background: #FFFFFF;
    color: #1C82FF;
}

.login-right form {
    width: 100%;
    max-width: 280px;
}

.pill-input-group {
    margin-bottom: 18px;
    width: 100%;
}

.pill-input-group input {
    width: 100%;
    padding: 12px 20px;
    border-radius: 50px;
    border: none;
    outline: none;
    font-size: 0.95rem;
    text-align: center;
    color: #2D3748;
    background: #FFFFFF;
    box-shadow: 0 4px 10px rgba(0,0,0,0.05);
}

.pill-input-group input::placeholder {
    color: #A0AEC0;
}

.pass-group {
    position: relative;
}

.eye-toggle {
    position: absolute;
    right: 15px;
    top: 50%;
    transform: translateY(-50%);
    cursor: pointer;
    color: #4A5568;
    font-size: 0.9rem;
}

.btn-pill-submit {
    width: 100%;
    padding: 12px;
    border-radius: 50px;
    border: none;
    background-color: #4CD964;
    color: #FFFFFF;
    font-weight: 800;
    font-size: 1rem;
    letter-spacing: 1.5px;
    cursor: pointer;
    box-shadow: 0 6px 15px rgba(76, 217, 100, 0.4);
    transition: transform 0.2s ease, background-color 0.2s ease;
}

.btn-pill-submit:hover {
    background-color: #44C759;
    transform: translateY(-2px);
}

/* RESPONSIVE DESIGN */
@media (max-width: 650px) {
    .login-card {
        flex-direction: column;
        height: auto;
    }
    .login-left {
        display: none;
    }
    .login-right {
        padding: 30px 20px;
    }
    .layout-with-sidebar {
        grid-template-columns: 1fr;
    }
}