:root {
    --primary-color: #0d6efd;
    --primary-gradient: linear-gradient(135deg, #0d6efd 0%, #0dcaf0 100%);
    --bg-color: #f8f9fa;
    --card-bg: #ffffff;
    --text-main: #212529;
    --text-muted: #6c757d;
    --nav-bg: rgba(255, 255, 255, 0.9);
    --border-color: #dee2e6;
    --shadow: 0 10px 30px rgba(0, 0, 0, 0.05);
}

[data-theme="dark"] {
    --bg-color: #0f172a;
    --card-bg: #1e293b;
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --nav-bg: rgba(15, 23, 42, 0.9);
    --border-color: #334155;
    --shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    transition: background-color 0.3s ease, color 0.3s ease;
    overflow-x: hidden;
}

/* Global Typography for Theme Support */
p,
li,
h1,
h2,
h3,
h4,
h5,
h6,
.lead {
    color: inherit;
}

[data-theme="dark"] body,
[data-theme="dark"] p,
[data-theme="dark"] li,
[data-theme="dark"] h1,
[data-theme="dark"] h2,
[data-theme="dark"] h3,
[data-theme="dark"] h4,
[data-theme="dark"] h5,
[data-theme="dark"] h6,
[data-theme="dark"] .lead,
[data-theme="dark"] .card {
    color: var(--text-main) !important;
}

label,
.form-label,
.form-check-label {
    color: var(--text-main);
    transition: color 0.3s ease;
}

[data-theme="dark"] .text-muted {
    color: var(--text-muted) !important;
}

[data-theme="dark"] .bg-light {
    background-color: rgba(255, 255, 255, 0.05) !important;
    color: var(--text-main) !important;
}

[data-theme="dark"] .accordion-item {
    background-color: var(--card-bg);
    border-color: var(--border-color);
}

[data-theme="dark"] .accordion-button {
    background-color: var(--card-bg);
    color: var(--text-main);
}

[data-theme="dark"] .accordion-button:not(.collapsed) {
    background-color: rgba(13, 110, 253, 0.1);
    color: var(--primary-color);
}

[data-theme="dark"] .accordion-button::after {
    filter: invert(1) grayscale(100%) brightness(200%);
}

.navbar {
    background-color: var(--nav-bg);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
}

.navbar-brand,
.nav-link {
    color: var(--text-main) !important;
}

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

.theme-toggle {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    background: var(--primary-gradient);
    color: white;
    transition: transform 0.3s ease;
}

.theme-toggle:hover {
    transform: scale(1.1);
}

.hero-section {
    padding: 60px 0 40px;
    text-align: center;
}

.animate-up {
    opacity: 0;
    transform: translateY(20px);
    animation: fadeInUp 0.6s forwards;
}

@keyframes fadeInUp {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.card {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 20px;
    box-shadow: var(--shadow);
    transition: background-color 0.3s ease, border-color 0.3s ease;
}

.form-control {
    background-color: var(--card-bg);
    border-color: var(--border-color);
    color: var(--text-main);
    border-radius: 10px;
    padding: 12px 15px;
}

.form-control:focus {
    background-color: var(--card-bg);
    color: var(--text-main);
    border-color: var(--primary-color);
    box-shadow: 0 0 0 0.25rem rgba(13, 110, 253, 0.15);
}

.btn-primary {
    background: var(--primary-gradient);
    border: none;
    border-radius: 10px;
    padding: 12px 25px;
    font-weight: 600;
}

.btn-outline-primary {
    border-radius: 10px;
}

.result-box {
    background: rgba(13, 110, 253, 0.05);
    border-radius: 15px;
    padding: 25px;
    border: 1px dashed var(--primary-color);
}

.footer {
    background-color: var(--card-bg);
    border-top: 1px solid var(--border-color);
    padding: 60px 0 30px;
    margin-top: 80px;
}

.footer .text-muted {
    color: var(--text-muted) !important;
}

.footer a.text-muted:hover {
    color: var(--primary-color) !important;
}

/* Advanced Mode Table */
.subject-row {
    margin-bottom: 15px;
}

.remove-subject {
    cursor: pointer;
    color: #dc3545;
    transition: color 0.2s;
}

.remove-subject:hover {
    color: #a71d2a;
}

@media (max-width: 768px) {
    .hero-section {
        padding: 40px 0 20px;
    }

    .card {
        padding: 25px !important;
    }
}