/* ========================================================
   ALGO-LAND | CSS UTAMA UNTUK LANDING PAGE
   Didesain untuk: Muhammad Abdul Mustofa (UI/UX)
======================================================== */

/* --- 1. SETUP & VARIABEL WARNA --- */
@import url('https://fonts.googleapis.com/css2?family=Montserrat:wght@400;500;700;800&display=swap');

:root {
    --primary-color: #2563EB;    /* Biru Profesional */
    --secondary-color: #F59E0B;  /* Oranye Enerjik (Tombol) */
    --dark-color: #1F2937;       /* Abu-abu Gelap (Teks/Footer) */
    --light-bg: #F9FAFB;         /* Latar Belakang Terang */
    --white: #FFFFFF;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Montserrat', sans-serif; /* Menggunakan font sesuai identitasmu */
}

body {
    background-color: var(--light-bg);
    color: var(--dark-color);
    line-height: 1.6;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* --- 2. NAVBAR --- */
nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.5rem 8%;
    background-color: var(--white);
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05);
    position: sticky;
    top: 0;
    z-index: 100;
}

.logo {
    font-size: 1.8rem;
    font-weight: 800;
    color: var(--primary-color);
    letter-spacing: -0.5px;
}

.menu {
    display: flex;
    list-style: none;
    gap: 2.5rem;
}

.menu li a {
    text-decoration: none;
    color: var(--dark-color);
    font-weight: 500;
    transition: color 0.3s ease;
}

.menu li a:hover {
    color: var(--primary-color);
}

/* --- 3. HERO SECTION (BAGIAN UTAMA) --- */
.hero-section {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 6rem 8%;
    flex: 1; /* Mendorong footer ke bawah */
}

.hero-text {
    flex: 1;
    padding-right: 3rem;
}

.hero-text h1 {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 1.5rem;
    color: var(--dark-color);
}

.hero-text p {
    font-size: 1.25rem;
    color: #4B5563;
    margin-bottom: 2.5rem;
}

#heroCanvas {
    background-color: #E5E7EB; /* Latar belakang abu-abu terang */
    border-radius: 20px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.1);
    max-width: 100%;
    /* Efek grid garis-garis samar seperti buku tulis/blueprint */
    background-image: linear-gradient(#D1D5DB 1px, transparent 1px), linear-gradient(90deg, #D1D5DB 1px, transparent 1px);
    background-size: 20px 20px;
}

.hero-text button {
    background-color: var(--secondary-color);
    color: var(--white);
    font-size: 1.1rem;
    font-weight: 700;
    padding: 1rem 2.5rem;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    box-shadow: 0 4px 14px 0 rgba(245, 158, 11, 0.39);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.hero-text button:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(245, 158, 11, 0.5);
}

.hero-image {
    flex: 1;
    display: flex;
    justify-content: flex-end;
}

/* Placeholder box jika gambar belum ada */
.hero-image img {
    max-width: 100%;
    height: auto;
    border-radius: 20px;
    background-color: #E5E7EB; /* Warna abu-abu sementara jika img gagal load */
    min-width: 400px;
    min-height: 300px;
}

/* --- 4. SECTION FITUR --- */
.features {
    padding: 5rem 8%;
    background-color: var(--white);
    text-align: center;
}

.features h2 {
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: var(--primary-color);
}

.fitur-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2.5rem;
}

.fitur-item {
    background-color: var(--light-bg);
    padding: 3rem 2rem;
    border-radius: 16px;
    border: 1px solid #E5E7EB;
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--dark-color);
    transition: transform 0.3s ease;
}

.fitur-item:hover {
    transform: translateY(-10px);
    border-color: var(--primary-color);
}

/* --- 4. SECTION FITUR --- */
.features {
    padding: 6rem 8%;
    background-color: var(--white);
}

.features-header {
    text-align: center;
    margin-bottom: 4rem;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

.features-header h2 {
    font-size: 2.5rem;
    color: var(--dark-color);
    margin-bottom: 1rem;
    font-weight: 800;
}

.features-header p {
    font-size: 1.1rem;
    color: #6B7280;
}

.fitur-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2.5rem;
}

.fitur-item {
    background-color: var(--white);
    padding: 2.5rem 2rem;
    border-radius: 20px;
    border: 1px solid #E5E7EB;
    text-align: left;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05);
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
}

.fitur-item:hover {
    transform: translateY(-8px);
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    border-color: var(--primary-color);
}

.fitur-icon {
    font-size: 3rem;
    margin-bottom: 1.5rem;
    background-color: #EFF6FF; /* Biru sangat muda */
    width: 70px;
    height: 70px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 16px;
}

.fitur-item h3 {
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--dark-color);
    margin-bottom: 1rem;
}

.fitur-item p {
    font-size: 1rem;
    color: #4B5563;
    line-height: 1.6;
}

/* --- 5. SECTION TENTANG (ABOUT) --- */
.about {
    padding: 6rem 8%;
    background-color: var(--light-bg);
}

.about-container {
    display: flex;
    align-items: center;
    gap: 4rem;
    background-color: var(--white);
    padding: 4rem;
    border-radius: 24px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.05);
}

.about-text {
    flex: 1;
}

.about-text h2 {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 1.5rem;
    font-weight: 800;
}

.about-text p {
    font-size: 1.1rem;
    color: #4B5563;
    margin-bottom: 1.5rem;
    line-height: 1.8;
}

.stats-container {
    display: flex;
    gap: 2rem;
    margin-top: 3rem;
    padding-top: 2rem;
    border-top: 1px solid #E5E7EB;
}

.stat-item h4 {
    font-size: 2rem;
    color: var(--secondary-color);
    font-weight: 800;
    margin-bottom: 0.2rem;
}

.stat-item span {
    font-size: 0.9rem;
    color: #6B7280;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.about-image {
    flex: 1;
    display: flex;
    justify-content: center;
}

.about-image img {
    max-width: 100%;
    border-radius: 16px;
    background-color: #E5E7EB; /* Placeholder abu-abu */
    min-height: 350px;
    width: 100%;
    object-fit: cover;
}

/* --- 5. FOOTER --- */
footer {
    background-color: var(--dark-color);
    color: var(--white);
    text-align: center;
    padding: 2.5rem;
    font-size: 1.1rem;
    font-weight: 500;
    margin-top: auto;
}

/* --- 6. MODAL AUTH & BLUR EFFECT --- */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(31, 41, 55, 0.4); /* Overlay gelap transparan */
    backdrop-filter: blur(8px); /* EFEK BLUR LATAR BELAKANG */
    display: none; /* Sembunyi secara default */
    align-items: center;
    justify-content: center;
    z-index: 1000;
    padding: 20px;
}

.modal-content {
    background: var(--white);
    width: 100%;
    max-width: 450px;
    padding: 40px;
    border-radius: 24px;
    position: relative;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    animation: slideUp 0.3s ease-out;
}

@keyframes slideUp {
    from { transform: translateY(20px); opacity: 0; }
    to { transform: translateY(0); opacity: 1; }
}

.close-btn {
    position: absolute;
    top: 20px;
    right: 25px;
    font-size: 2rem;
    background: none;
    border: none;
    cursor: pointer;
    color: #9CA3AF;
}

/* Form Styling */
.auth-header { text-align: center; margin-bottom: 30px; }
.auth-header h3 { font-size: 1.8rem; color: var(--dark-color); margin-bottom: 8px; }

.input-group { margin-bottom: 20px; }
.input-group label { display: block; font-weight: 600; margin-bottom: 8px; font-size: 0.9rem; }
.input-group input, .input-group select {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid #E5E7EB;
    border-radius: 10px;
    font-size: 1rem;
}

.auth-submit {
    width: 100%;
    padding: 14px;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 10px;
    font-weight: 700;
    cursor: pointer;
    margin-top: 10px;
}

.switch-auth { text-align: center; margin-top: 20px; font-size: 0.9rem; }
.switch-auth a { color: var(--primary-color); text-decoration: none; font-weight: 600; }

/* --- 6. RESPONSIVE DESIGN (Biar aman di HP) --- */
@media (max-width: 768px) {
    .hero-section {
        flex-direction: column;
        text-align: center;
        padding: 3rem 5%;
    }
    
    .hero-text {
        padding-right: 0;
        margin-bottom: 3rem;
    }
    
    .hero-text h1 {
        font-size: 2.5rem;
    }
    
    .menu {
        display: none; /* Sembunyikan menu di mobile untuk sementara */
    }
    
    .hero-image {
        justify-content: center;
    }

    /* Tambahkan ini di dalam @media (max-width: 768px) */
    .about-container {
        flex-direction: column;
        padding: 2rem;
        text-align: center;
    }
    
    .stats-container {
        flex-direction: column;
        gap: 1.5rem;
        align-items: center;
    }
}