/* Tối ưu hóa mặc định */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Poppins', sans-serif;
}

/* --- HỆ MÀU MATCHA & CÁC BIẾN --- */
:root {
    --matcha-lightest: #f3f8f4; /* Nền mờ, xám xanh rất nhạt */
    --matcha-light: #cde0d2;    /* Xanh matcha nhạt (hover, badge) */
    --matcha-primary: #85af90;  /* Màu chủ đạo của nút, nhấn */
    --matcha-dark: #5c8466;     /* Màu đậm cho header, hover nút */
    --text-dark: #2a3a30;       /* Chữ đen ngả xanh lá */
    --text-gray: #5a7364;       /* Chữ đoạn văn */
    --white: #ffffff;
    --shadow: 0 10px 30px rgba(92, 132, 102, 0.08);
}

body {
    background-color: var(--white);
    color: var(--text-dark);
    line-height: 1.6;
}

a {
    text-decoration: none;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* --- COMPONENTS: NÚT BẤM (BUTTONS) --- */
.btn {
    display: inline-block;
    padding: 12px 28px;
    border-radius: 50px;
    font-weight: 500;
    transition: all 0.3s ease;
    cursor: pointer;
    text-align: center;
}

.btn-primary {
    background-color: var(--matcha-primary);
    color: var(--white);
    border: 2px solid var(--matcha-primary);
}

.btn-primary:hover {
    background-color: var(--matcha-dark);
    border-color: var(--matcha-dark);
    transform: translateY(-2px);
}

.btn-outline {
    background-color: transparent;
    color: var(--matcha-dark);
    border: 2px solid var(--matcha-light);
}

.btn-outline:hover {
    border-color: var(--matcha-primary);
    background-color: var(--matcha-lightest);
}

.btn-dark {
    background-color: var(--matcha-dark);
    color: var(--white);
    border: none;
}

.btn-dark:hover {
    background-color: var(--text-dark);
}

/* --- NAVBAR --- */
.navbar {
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    border-bottom: 1px solid var(--matcha-lightest);
}

.nav-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 80px;
}

.logo {
    font-size: 24px;
    font-weight: 700;
    color: var(--text-dark);
}

.logo span {
    color: var(--matcha-primary);
}

.nav-links a {
    margin: 0 15px;
    color: var(--text-dark);
    font-weight: 500;
    transition: color 0.3s ease;
}

.nav-links a:hover {
    color: var(--matcha-primary);
}

/* --- HERO SECTION --- */
.hero {
    padding: 160px 0 100px;
    background-color: var(--matcha-lightest);
    overflow: hidden;
}

.hero-content {
    display: flex;
    align-items: center;
    gap: 50px;
}

.hero-text {
    flex: 1;
}

.badge {
    background-color: var(--matcha-light);
    color: var(--matcha-dark);
    padding: 6px 14px;
    border-radius: 20px;
    font-size: 14px;
    font-weight: 600;
    display: inline-block;
    margin-bottom: 20px;
}

.hero-text h1 {
    font-size: 48px;
    line-height: 1.2;
    margin-bottom: 20px;
    color: var(--text-dark);
}

.hero-text h1 span {
    color: var(--matcha-primary);
}

.hero-text p {
    font-size: 18px;
    color: var(--text-gray);
    margin-bottom: 30px;
}

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

.hero-image {
    flex: 1;
}

.image-placeholder {
    width: 100%;
    height: 400px;
    background: linear-gradient(135deg, var(--matcha-light), var(--matcha-primary));
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--white);
    font-weight: 500;
    box-shadow: var(--shadow);
    img {
        width: 100%;
        height: 100%;
    }
}

/* --- FEATURES SECTION --- */
.features {
    padding: 100px 0;
    background-color: var(--white);
}

.section-title {
    text-align: center;
    max-width: 600px;
    margin: 0 auto 60px;
}

.section-title h2 {
    font-size: 36px;
    color: var(--text-dark);
    margin-bottom: 15px;
}

.section-title p {
    color: var(--text-gray);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.feature-card {
    background-color: var(--white);
    padding: 40px 30px;
    border-radius: 20px;
    box-shadow: var(--shadow);
    border: 1px solid var(--matcha-lightest);
    transition: transform 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-10px);
}

.feature-card .icon {
    font-size: 40px;
    margin-bottom: 20px;
    background-color: var(--matcha-lightest);
    width: 80px;
    height: 80px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 20px;
}

.feature-card h3 {
    font-size: 20px;
    margin-bottom: 15px;
    color: var(--text-dark);
}

.feature-card p {
    color: var(--text-gray);
    font-size: 15px;
}

/* --- CTA SECTION --- */
.cta-section {
    padding: 80px 0;
    background-color: var(--matcha-primary);
    text-align: center;
}

.cta-content h2 {
    color: var(--white);
    font-size: 32px;
    margin-bottom: 15px;
}

.cta-content p {
    color: var(--matcha-lightest);
    margin-bottom: 30px;
}

.cta-form {
    display: flex;
    justify-content: center;
    gap: 10px;
    max-width: 500px;
    margin: 0 auto;
}

.cta-form input {
    flex: 1;
    padding: 12px 20px;
    border-radius: 50px;
    border: none;
    outline: none;
    font-size: 16px;
}

/* --- FOOTER --- */
.footer {
    background-color: var(--matcha-lightest);
    padding: 80px 0 20px;
    color: var(--text-dark);
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 40px;
}

.brand-col p {
    margin-top: 15px;
    color: var(--text-gray);
    font-size: 14px;
}

.footer-col h4 {
    margin-bottom: 20px;
    font-size: 18px;
}

.footer-col ul {
    list-style: none;
}

.footer-col ul li {
    margin-bottom: 10px;
}

.footer-col ul li a {
    color: var(--text-gray);
    transition: color 0.3s ease;
    font-size: 14px;
}

.footer-col ul li a:hover {
    color: var(--matcha-primary);
}

.footer-col p {
    color: var(--text-gray);
    font-size: 14px;
    margin-bottom: 10px;
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid var(--matcha-light);
    color: var(--text-gray);
    font-size: 14px;
}
/* --- BỔ SUNG CSS CHO MODAL ĐĂNG NHẬP --- */
.modal {
    position: fixed;
    top: 0; left: 0; width: 100%; height: 100%;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    opacity: 1;
    transition: opacity 0.3s ease;
}
.modal.hidden {
    opacity: 0;
    pointer-events: none;
}
.modal-content {
    background: #fff;
    padding: 30px;
    border-radius: 16px;
    width: 90%;
    max-width: 400px;
    position: relative;
    box-shadow: 0 20px 40px rgba(0,0,0,0.2);
    transform: translateY(0);
    transition: transform 0.3s ease;
}
.modal.hidden .modal-content {
    transform: translateY(-20px);
}
.close-modal {
    position: absolute;
    top: 15px; right: 20px;
    font-size: 24px;
    cursor: pointer;
    color: #666;
}
.auth-tabs {
    display: flex;
    margin-bottom: 20px;
    border-bottom: 2px solid #eee;
}
.auth-tab {
    flex: 1;
    background: none; border: none;
    padding: 10px;
    font-size: 16px; font-weight: 600;
    color: #888;
    cursor: pointer;
    border-bottom: 2px solid transparent;
    transition: all 0.3s ease;
}
.auth-tab.active {
    color: var(--matcha-primary, #81c784);
    border-bottom-color: var(--matcha-primary, #81c784);
}
.form-group {
    margin-bottom: 15px;
}
.form-group label {
    display: block; margin-bottom: 5px;
    font-weight: 500; font-size: 14px;
}
.form-group input {
    width: 100%;
    padding: 10px 15px;
    border: 1px solid #ddd;
    border-radius: 8px;
    font-family: 'Poppins', sans-serif;
}
.error-msg {
    color: red; font-size: 13px; margin-bottom: 10px;
}
.w-100 { width: 100%; }
.auth-form.hidden { display: none; }
/* --- RESPONSIVE DESIGN --- */
@media (max-width: 768px) {
    .hero-content {
        flex-direction: column;
        text-align: center;
    }
    
    .hero-buttons {
        justify-content: center;
    }

    .hero-text h1 {
        font-size: 36px;
    }

    .nav-links {
        display: none; /* Trong thực tế sẽ dùng hamburger menu */
    }

    .footer-grid {
        grid-template-columns: 1fr;
    }
    
    .cta-form {
        flex-direction: column;
    }
}