:root {
    /* Light Theme (Default) */
    --bg-main: #F8F5FC;
    --card-bg: rgba(255, 255, 255, 0.7);
    --card-border: rgba(0, 0, 0, 0.05);
    --accent-color: #B8E0D2;
    --accent-color-hover: #98D0BC;
    --text-main: #2D3748;
    --text-dim: #718096;
    --border-color: #E2E8F0;
    --correct-green: #10b981;
    --wrong-red: #ef4444;
    --correct-bg: #d1fae5;
    --wrong-bg: #fee2e2;

    /* Logo */
    --logo-fill: #1A202C;
    --logo-stroke: #1A202C;
    --logo-glow: rgba(184, 224, 210, 0.8);
    --logo-header-inner: #F8F5FC;
    --logo-center-inner: #FFFFFF;

    /* Ambient Glows (Kept for buttons/shadows, not background) */
    --btn-glow: rgba(184, 224, 210, 0.8);

    /* Header & General */
    --header-bg: rgba(248, 245, 252, 0.85);
    --dropdown-bg: #FFFFFF;
    --nav-bg: rgba(255, 255, 255, 0.85);
    --disclaimer-bg: #FFFFFF;
}

[data-theme="dark"] {
    /* Dark Theme */
    --bg-main: #1A1820;
    --card-bg: rgba(30, 28, 36, 0.7);
    --card-border: rgba(255, 255, 255, 0.05);
    --accent-color: #8C7B9B;
    --accent-color-hover: #A393B3;
    --text-main: #E2E8F0;
    --text-dim: #A0AEC0;
    --border-color: rgba(255, 255, 255, 0.1);
    --correct-green: #34d399;
    --wrong-red: #f87171;
    --correct-bg: #064e3b;
    --wrong-bg: #7f1d1d;

    /* Logo */
    --logo-fill: #E2E8F0;
    --logo-stroke: #E2E8F0;
    --logo-glow: rgba(140, 123, 155, 0.8);
    --logo-header-inner: #1A1820;
    --logo-center-inner: #1D1B23;

    /* Ambient Glows (Kept for buttons/shadows, not background) */
    --btn-glow: rgba(140, 123, 155, 0.8);

    /* Header & General */
    --header-bg: rgba(26, 24, 32, 0.85);
    --dropdown-bg: #221F2A;
    --nav-bg: rgba(30, 28, 36, 0.85);
    --disclaimer-bg: #221F2A;
}

html {
    overflow-x: hidden;
    max-width: 100vw;
}

body {
    font-family: 'Nunito', sans-serif;
    color: var(--text-main);
    overflow-x: hidden;
    max-width: 100vw;
    -webkit-tap-highlight-color: transparent;
    transition: color 0.5s ease;
    /* Static Vector Gradient Background */
    background: radial-gradient(circle at 15% 15%, rgba(152, 208, 188, 0.3) 0%, transparent 60%),
                radial-gradient(circle at 85% 85%, rgba(184, 224, 210, 0.4) 0%, transparent 65%),
                radial-gradient(circle at 40% 60%, rgba(200, 240, 220, 0.25) 0%, transparent 70%),
                var(--bg-main);
    background-attachment: fixed;
}

[data-theme="dark"] body {
    background: radial-gradient(circle at 15% 15%, rgba(163, 133, 193, 0.5) 0%, transparent 60%),
                radial-gradient(circle at 85% 85%, rgba(186, 153, 219, 0.5) 0%, transparent 65%),
                radial-gradient(circle at 40% 60%, rgba(140, 90, 220, 0.35) 0%, transparent 70%),
                var(--bg-main);
    background-attachment: fixed;
}

.font-fredoka {
    font-family: 'Fredoka', sans-serif;
}

/* Cinematic Vignette */
body::before {
    content: "";
    position: fixed;
    inset: 0;
    z-index: -1;
    pointer-events: none;
    background: radial-gradient(circle at center, transparent 0%, rgba(0, 0, 0, 0.05) 100%);
}

[data-theme="dark"] body::before {
    background: radial-gradient(circle at center, transparent 0%, rgba(5, 5, 5, 0.85) 100%);
}

/* Glass Card Design */
.glass-card {
    background: var(--card-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--card-border);
    border-radius: 2rem;
    position: relative;
    z-index: 10;
    box-shadow:
        0 10px 30px -10px rgba(0, 0, 0, 0.1),
        inset 0 0 0 1px rgba(255, 255, 255, 0.1);
    transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

[data-theme="dark"] .glass-card {
    box-shadow:
        0 25px 50px -12px rgba(0, 0, 0, 0.5),
        inset 0 1px 1px rgba(255, 255, 255, 0.05);
}

/* Accent Buttons */
.btn-accent {
    background-color: var(--accent-color);
    color: var(--text-main);
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    border: 1px solid var(--border-color);
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05);
    cursor: pointer;
}

.btn-accent:hover:not(:disabled) {
    background-color: var(--accent-color-hover);
    transform: translateY(-3px) scale(1.02);
    box-shadow: 0 15px 25px -5px var(--btn-glow);
}

.btn-accent:active:not(:disabled) {
    transform: scale(0.98) translateY(0);
}

.btn-accent:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* Module Cards */
.module-card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    border-radius: 1.25rem;
}

.module-card:hover {
    border-color: var(--accent-color);
    background: var(--bg-main);
    box-shadow: 0 20px 30px -10px rgba(0, 0, 0, 0.1);
    transform: translateY(-5px) scale(1.03);
}

/* Ribbon */
.ribbon-wrapper {
    position: absolute;
    top: -1px;
    right: -1px;
    width: 85px;
    height: 85px;
    overflow: hidden;
    border-radius: 0 1.5rem 0 0;
}

.ribbon {
    position: absolute;
    top: 15px;
    right: -25px;
    background: var(--accent-color);
    color: var(--text-main);
    text-align: center;
    font-size: 7px;
    font-weight: 900;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    padding: 5px 0;
    width: 120px;
    transform: rotate(45deg);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

/* Author Dropdown */
.author-dropdown-up {
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    opacity: 0;
    transform: translateY(10px) translateX(-50%) scale(0.95);
    pointer-events: none;
    background: var(--dropdown-bg);
    border-color: var(--border-color);
}

.author-dropdown-up::after {
    content: "";
    position: absolute;
    bottom: -20px;
    left: 0;
    width: 100%;
    height: 25px;
    background: transparent;
}

.group:hover .author-dropdown-up,
.author-dropdown-up.active {
    opacity: 1;
    transform: translateY(0) translateX(-50%) scale(1);
    pointer-events: auto;
}

/* Social Buttons */
.social-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0.6rem 1rem;
    border-radius: 0.75rem;
    font-size: 10px;
    font-weight: 900;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    transition: all 0.3s ease;
    position: relative;
    z-index: 60;
}

.social-btn.insta {
    background: linear-gradient(45deg, #f09433 0%, #e6683c 25%, #dc2743 50%, #cc2366 75%, #bc1888 100%);
    color: white;
}

.social-btn.tg {
    background: #0088cc;
    color: white;
}

.social-btn:hover {
    transform: translateY(-2px);
    filter: brightness(1.1);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.15);
}

/* Logo Effects */
.logo-container {
    cursor: pointer;
    display: flex;
    align-items: center;
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    position: relative;
    padding-bottom: 4px;
}

.logo-container::after {
    content: "";
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent-color-hover);
    box-shadow: 0 0 10px var(--accent-color-hover), 0 0 20px var(--accent-color-hover);
    transition: none;
    border-radius: 2px;
}

.logo-container:hover::after {
    animation: logo-line-run 0.6s ease-out forwards;
}

.logo-container:hover .logo-invictus,
.logo-container:hover .logo-medline-header,
.logo-container:hover .logo-medline-center {
    animation: logo-heartbeat-flash 0.8s 0.5s ease-in-out forwards;
}

@keyframes logo-line-run {
    0% { width: 0; left: 0; opacity: 1; }
    90% { width: 100%; left: 0; opacity: 1; }
    100% { width: 100%; left: 0; opacity: 0; }
}

@keyframes logo-heartbeat-flash {
    0% { text-shadow: 0 0 0 transparent; transform: scale(1); }
    15% { text-shadow: 0 0 20px var(--logo-glow), 0 0 35px var(--logo-glow); transform: scale(1.03); }
    30% { text-shadow: 0 0 5px var(--logo-glow); transform: scale(1); }
    45% { text-shadow: 0 0 15px var(--logo-glow), 0 0 25px var(--logo-glow); transform: scale(1.015); }
    70% { text-shadow: 0 0 0 transparent; transform: scale(1); }
    100% { text-shadow: 0 0 0 transparent; transform: scale(1); }
}

.logo-invictus {
    color: var(--logo-fill);
    transition: all 0.5s ease;
}

.logo-medline-header,
.logo-medline-center {
    transition: all 0.5s ease;
    paint-order: stroke fill;
    -webkit-text-stroke: 1.5px var(--logo-stroke);
    font-weight: 800;
}

.logo-medline-header {
    color: var(--logo-header-inner);
}

.logo-medline-center {
    color: var(--logo-center-inner);
}

/* Shared Dropdown / Select styling */
.dropdown-btn {
    transition: background-color 0.2s ease;
}

.dropdown-btn:hover {
    background-color: var(--card-border);
}

select option {
    background-color: var(--dropdown-bg);
    color: var(--text-main);
    font-weight: bold;
}

/* Quiz Specific */
.quiz-item {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 1.25rem;
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

.quiz-item:hover {
    border-color: var(--accent-color);
}

@media (min-width: 768px) {
    .quiz-item {
        padding: 2.5rem;
        margin-bottom: 2rem;
    }
}

.question-content {
    text-transform: none !important;
    line-height: 1.6;
}

.question-content b,
.question-content mark {
    font-weight: 800;
    background: transparent;
    color: inherit;
    transition: color 0.5s ease, text-shadow 0.5s ease;
}

.question-content.show-keywords b,
.question-content.show-keywords mark {
    color: var(--accent-color-hover);
    text-shadow: 0 0 10px var(--btn-glow);
}

.option-btn {
    width: 100%;
    text-align: left;
    padding: 1rem 1.5rem;
    border-radius: 1rem;
    border: 1px solid var(--border-color);
    background: transparent;
    margin-top: 0.75rem;
    transition: all 0.2s ease;
    font-size: 1rem;
    display: flex;
    align-items: center;
    color: var(--text-main);
    cursor: pointer;
}

.option-btn:hover:not(.disabled) {
    background: var(--border-color);
}

.option-btn.correct {
    background: var(--correct-bg) !important;
    border-color: var(--correct-green) !important;
    color: var(--text-main);
    font-weight: 700;
}

.option-btn.wrong {
    background: var(--wrong-bg) !important;
    border-color: var(--wrong-red) !important;
    color: var(--text-main);
}

@keyframes breathe-correct {
    0% { box-shadow: 0 0 5px rgba(16, 185, 129, 0.4); }
    50% { box-shadow: 0 0 20px rgba(16, 185, 129, 0.8); }
    100% { box-shadow: 0 0 5px rgba(16, 185, 129, 0.4); }
}

.breathe-correct {
    animation: breathe-correct 2s ease-in-out infinite;
    border-color: var(--correct-green) !important;
    font-weight: 700;
}

@keyframes pulse-wrong {
    0%, 100% { box-shadow: 0 0 20px rgba(239, 68, 68, 0.3); transform: scale(1); border-color: var(--wrong-red); color: var(--wrong-red); }
    50% { box-shadow: 0 0 40px rgba(239, 68, 68, 0.6); transform: scale(1.05); border-color: var(--wrong-red); text-shadow: 0 0 10px rgba(239, 68, 68, 0.5); }
}

@keyframes pulse-correct {
    0%, 100% { box-shadow: 0 0 20px rgba(16, 185, 129, 0.3); transform: scale(1); border-color: var(--correct-green); color: var(--correct-green); }
    50% { box-shadow: 0 0 40px rgba(16, 185, 129, 0.6); transform: scale(1.02); border-color: var(--correct-green); text-shadow: 0 0 10px rgba(16, 185, 129, 0.5); }
}

.pulse-wrong { animation: pulse-wrong 0.5s infinite ease-in-out; }
.pulse-correct { animation: pulse-correct 1s infinite ease-in-out; }
.option-btn.disabled { cursor: default; }

.custom-checkbox {
    accent-color: var(--accent-color);
    width: 1.2rem;
    height: 1.2rem;
    cursor: pointer;
    border-radius: 4px;
}

/* Nav Panel (Quiz) */
.nav-panel {
    background: var(--nav-bg);
    backdrop-filter: blur(16px);
    border: 1px solid var(--border-color);
    border-radius: 1.5rem;
    padding: 1.5rem;
    overflow-y: auto;
    position: relative;
    z-index: 50;
    transition: background-color 0.5s ease;
}

@media (max-width: 1023px) {
    .nav-panel {
        position: fixed;
        top: 4rem;
        right: 0;
        bottom: 0;
        width: 80vw;
        max-width: 320px;
        z-index: 200;
        border-radius: 1.5rem 0 0 0;
        border-left: 1px solid var(--border-color);
        border-top: 1px solid var(--border-color);
        border-bottom: none;
        border-right: none;
        transform: translateX(100%);
        transition: transform 0.5s cubic-bezier(0.19, 1, 0.22, 1);
        background: var(--header-bg);
        padding: 1.5rem;
    }
    .nav-panel.active { transform: translateX(0); box-shadow: -30px 0 60px rgba(0, 0, 0, 0.15); }
    [data-theme="dark"] .nav-panel.active { box-shadow: -30px 0 60px rgba(0, 0, 0, 0.8); }
    .nav-overlay {
        position: fixed;
        inset: 0;
        background: rgba(0, 0, 0, 0.4);
        backdrop-filter: blur(8px);
        z-index: 190;
        opacity: 0;
        pointer-events: none;
        transition: opacity 0.5s ease;
    }
    .nav-overlay.active { opacity: 1; pointer-events: auto; }
}

@media (min-width: 1024px) {
    .nav-panel {
        width: 320px;
        height: calc(100vh - 240px);
        position: sticky;
        top: 120px;
        max-height: none;
    }
}

.nav-dot {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 0.75rem;
    font-size: 0.75rem;
    font-weight: 800;
    background: transparent;
    color: var(--text-dim);
    cursor: pointer;
    border: 1px solid var(--border-color);
    transition: all 0.2s ease;
}

.nav-dot.answered {
    background: var(--accent-color);
    color: var(--text-main);
    border-color: var(--accent-color);
}

.nav-dot:hover {
    border-color: var(--accent-color);
    color: var(--text-main);
}

.no-scrollbar::-webkit-scrollbar { display: none; }
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border-color); border-radius: 10px; }
::-webkit-scrollbar-thumb:hover { background: var(--accent-color); }

/* News specific */
.patch-category {
    border-left: 4px solid var(--accent-color-hover);
    padding-left: 1.5rem;
    margin-bottom: 2.5rem;
    position: relative;
}

.patch-category::before {
    content: "";
    position: absolute;
    left: -4px;
    top: 0;
    height: 20%;
    width: 4px;
    background: var(--text-main);
}

.category-title {
    font-family: 'Fredoka', sans-serif;
    font-size: 1.25rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--text-main);
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.patch-item {
    position: relative;
    padding-left: 1.25rem;
    margin-bottom: 0.75rem;
    font-size: 0.95rem;
    line-height: 1.6;
}

.patch-item::before {
    content: "•";
    position: absolute;
    left: 0;
    color: var(--accent-color-hover);
    font-weight: 900;
}

.patch-item b {
    color: var(--text-main);
    font-weight: 800;
}

.version-badge {
    background: var(--accent-color-hover);
    color: var(--bg-main);
    padding: 0.25rem 0.75rem;
    border-radius: 2rem;
    font-weight: 900;
    font-size: 0.75rem;
    letter-spacing: 0.1em;
}

/* Responsive tweaks */
@media (max-width: 640px) {
    .brand-subtitle {
        letter-spacing: 0.2em !important;
        font-size: 9px !important;
    }
}