/* ==========================================================================
   ACE Nursing Exams - Consolidated Modern Variable Stylesheet 
   ========================================================================== */

:root {
    /* Theme - Dark Default Base Variables */
    --bg: #0b1220;
    --card: #0f172a;
    --muted: #94a3b8;
    --text: #e2e8f0;
    --primary: #0ea5a4;
    --primary-gradient: linear-gradient(135deg, #0ea5a4, #14b8a6);
    --border-color: rgba(148, 163, 184, 0.1);
    --hover-bg: rgba(148, 163, 184, 0.08);
}

/* ==========================================================================
   Consolidated Smooth Global Theme Engine Transition
   ========================================================================== */
body, 
body *, 
body *::before, 
body *::after {
    transition: background-color 0.3s ease, 
                background 0.3s ease, 
                color 0.3s ease, 
                border-color 0.3s ease, 
                box-shadow 0.3s ease;
}

/* Light Mode Override Variable Tokens */
body.light-mode {
    --bg: #f8fafc;
    --card: #ffffff;
    --muted: #64748b;
    --text: #1e293b;
    --primary: #0f766e;
    --primary-gradient: linear-gradient(135deg, #0f766e, #14b8a6);
    --border-color: rgba(0, 0, 0, 0.08);
    --hover-bg: rgba(15, 118, 110, 0.05);
}

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

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg);
    color: var(--text);
    line-height: 1.6;
    transition: background-color 0.3s ease, color 0.3s ease;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* ===== APP HEADER (NAVIGATION BAR) ===== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: var(--bg);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    padding: 14px 0;
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.4rem;
    font-weight: 700;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    text-decoration: none;
    letter-spacing: -0.5px;
}

.nav-links {
    display: flex;
    gap: 24px;
    align-items: center;
}

.nav-links a {
    color: var(--muted);
    text-decoration: none;
    font-weight: 500;
    font-size: 0.95rem;
    transition: color 0.2s ease;
}

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

/* UI Interactive Components */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 10px 22px;
    border-radius: 8px;
    font-weight: 600;
    text-decoration: none;
    font-size: 0.95rem;
    border: none;
    cursor: pointer;
    transition: all 0.2s ease;
}

.btn-primary {
    background: var(--primary-gradient);
    color: #ffffff !important;
}

.btn-primary:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(14, 165, 164, 0.25);
}

.btn-outline {
    border: 1px solid var(--border-color);
    background: transparent;
    color: var(--text) !important;
}

.btn-outline:hover {
    border-color: var(--primary);
    background: var(--hover-bg);
    color: var(--primary) !important;
}

.theme-toggle {
    background: transparent;
    border: none;
    cursor: pointer;
    font-size: 1.2rem;
    color: var(--text);
    padding: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    transition: background 0.2s;
}

.theme-toggle:hover {
    background: var(--hover-bg);
}

.mobile-menu-btn {
    display: none;
    background: transparent;
    border: none;
    font-size: 1.4rem;
    cursor: pointer;
    color: var(--text);
}

/* ===== AUTH CARD & UI WRAPPERS ===== */
.auth-container {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 100px 20px 40px;
}

.auth-card {
    background: var(--card);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 36px;
    width: 100%;
    max-width: 440px;
    box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.1);
}

.form-group {
    margin-bottom: 18px;
}

.form-group label {
    display: block;
    margin-bottom: 6px;
    font-weight: 500;
    font-size: 0.9rem;
}

.form-group input {
    width: 100%;
    padding: 11px 14px;
    background: var(--bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    color: var(--text);
    font-size: 0.95rem;
    transition: border-color 0.2s ease;
}

.form-group input:focus {
    outline: none;
    border-color: var(--primary);
}

/* ===== RESPONSIVE MEDIA QUERIES ===== */
@media (max-width: 768px) {
    .mobile-menu-btn {
        display: block;
    }

    .nav-links {
        position: fixed;
        top: 65px;
        left: 0;
        right: 0;
        background: var(--card);
        border-bottom: 1px solid var(--border-color);
        padding: 24px;
        flex-direction: column;
        gap: 16px;
        align-items: stretch;
        display: none; /* Controlled via JS class toggles */
        box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    }

    .nav-links.active {
        display: flex;
    }

    .nav-links .theme-toggle {
        align-self: center;
        width: max-content;
    }
}