@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@300;400;500;600;700&display=swap');

:root {
    --bg-color: #f8fafc;
    --text-primary: #0f172a;
    --text-secondary: #64748b;
    --primary: #3b82f6;
    --primary-hover: #2563eb;
    --border: #e2e8f0;
    
    --nav-height: 80px;
}

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

body {
    font-family: 'Outfit', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.6;
}

/* NAVBAR STRUCTURE */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: var(--nav-height);
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--border);
    z-index: 1000;
}

.nav-container {
    max-width: 1200px;
    height: 100%;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

/* BRANDING */
.brand {
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    z-index: 1010;
}

.logo-box {
    background: var(--primary);
    color: white;
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 8px;
    font-weight: 800;
}

/* MOBILE TOGGLE (HIDDEN ON DESKTOP) */
.nav-toggle {
    display: none;
}

.nav-toggle-label {
    display: none;
    cursor: pointer;
    z-index: 1010;
}

.hamburger {
    position: relative;
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    transition: all 0.3s ease-in-out;
}

.hamburger::before,
.hamburger::after {
    content: '';
    position: absolute;
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    transition: all 0.3s ease-in-out;
}

.hamburger::before { top: -8px; }
.hamburger::after { bottom: -8px; }

/* NAVIGATION MENU */
.nav-menu {
    display: flex;
    align-items: center;
    gap: 3rem;
}

.nav-list {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    font-size: 0.95rem;
    position: relative;
    padding: 0.5rem 0;
    transition: color 0.3s;
}

.nav-link:hover {
    color: var(--primary);
}

/* Hover Animation (Underline Expansion) */
.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0%;
    height: 2px;
    background-color: var(--primary);
    transition: width 0.3s ease;
}

.nav-link:hover::after {
    width: 100%;
}

/* BUTTONS */
.nav-cta {
    display: flex;
    gap: 1rem;
    align-items: center;
}

.btn {
    text-decoration: none;
    padding: 0.7rem 1.25rem;
    border-radius: 8px;
    font-weight: 600;
    font-size: 0.9rem;
    transition: all 0.2s;
}

.btn-login {
    color: var(--text-primary);
}

.btn-login:hover {
    color: var(--primary);
}

.btn-signup {
    background: var(--primary);
    color: white;
    box-shadow: 0 4px 14px 0 rgba(59, 130, 246, 0.39);
}

.btn-signup:hover {
    background: var(--primary-hover);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(59, 130, 246, 0.23);
}

/* CONTENT PLACEHOLDER */
.content-placeholder {
    padding: 12rem 2rem 4rem;
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.content-placeholder h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.content-placeholder p {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.features-list {
    text-align: left;
    max-width: 400px;
    margin: 0 auto;
    line-height: 2;
}

.features-list i {
    color: var(--primary);
    margin-right: 0.5rem;
}

/* RESPONSIVE STYLES */
@media screen and (max-width: 900px) {
    .nav-toggle-label {
        display: block;
    }

    .nav-menu {
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background: white;
        flex-direction: column;
        gap: 0;
        height: 0;
        overflow: hidden;
        transition: height 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
        border-bottom: 1px solid var(--border);
        box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    }

    .nav-list {
        flex-direction: column;
        width: 100%;
        gap: 0;
    }

    .nav-list li {
        width: 100%;
    }

    .nav-link {
        display: block;
        padding: 1.5rem 2rem;
        border-bottom: 1px solid var(--border);
        font-size: 1.1rem;
    }

    .nav-link::after {
        display: none; /* remove hover animation on mobile */
    }

    .nav-cta {
        flex-direction: column;
        width: 100%;
        padding: 2rem;
        gap: 1rem;
    }

    .btn {
        width: 100%;
        text-align: center;
        padding: 1rem;
    }

    .btn-login {
        border: 1px solid var(--border);
    }

    /* Checkbox state styling */
    .nav-toggle:checked ~ .nav-menu {
        height: 480px; /* arbitrary height to fit contents */
    }

    .nav-toggle:checked ~ .nav-toggle-label .hamburger {
        background: transparent;
    }

    .nav-toggle:checked ~ .nav-toggle-label .hamburger::before {
        transform: rotate(45deg);
        top: 0;
    }

    .nav-toggle:checked ~ .nav-toggle-label .hamburger::after {
        transform: rotate(-45deg);
        bottom: 0;
    }
}