/* ===========================================
   FIZICA CU FEYNMAN — styles.css
   =========================================== */

:root {
    --primary-dark:   #1F4E79;
    --primary-medium: #2E75B6;
    --primary-light:  #5B9BD5;
    --accent:         #E8A000;
    --bg-light:       #F7FAFD;
    --text-dark:      #2C3E50;
    --text-light:     #6C757D;
    --border:         #DEE2E6;
    --white:          #ffffff;
    --shadow:         0 2px 8px rgba(0,0,0,0.08);
    --shadow-lg:      0 8px 24px rgba(0,0,0,0.13);
    --radius:         6px;
}

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

body {
    font-family: 'Segoe UI', system-ui, sans-serif;
    line-height: 1.7;
    color: var(--text-dark);
    background: var(--white);
}

/* ——— MODULE PAGE WRAPPER ——— */
.module-page {
    max-width: 900px;
    margin: 0 auto;
    padding: 0 24px 48px;
}

/* ——— NAVBAR (index) ——— */
.navbar {
    background: linear-gradient(135deg, var(--primary-dark), var(--primary-medium));
    padding: 0.9rem 2rem;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: var(--shadow);
}
.navbar-container {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.navbar-brand {
    color: var(--white);
    text-decoration: none;
    font-size: 1.3rem;
    font-weight: 700;
}
.navbar-brand:hover { color: var(--accent); }
.navbar-nav { display: flex; list-style: none; gap: 1.5rem; }
.navbar-nav a { color: rgba(255,255,255,0.9); text-decoration: none; font-weight: 500; }
.navbar-nav a:hover { color: var(--accent); }

/* ——— HERO ——— */
.hero {
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary-medium) 100%);
    color: var(--white);
    padding: 1.8rem 2rem;
    text-align: center;
}
.hero h1 {
    font-size: 2.2rem;
    margin-bottom: 0.35rem;
    color: var(--white);
    border: none;
    padding: 0;
    margin-top: 0;
    text-shadow: 0 1px 3px rgba(0,0,0,0.25);
}
.hero p {
    font-size: 0.95rem;
    opacity: 0.88;
    max-width: 640px;
    margin: 0 auto;
}

/* ——— INDEX: CONTAINER & GRID ——— */
.container { max-width: 1200px; margin: 0 auto; padding: 2rem; }
.section-title { text-align: center; margin-bottom: 2rem; }
.section-title h2 { font-size: 1.8rem; color: var(--primary-dark); margin-bottom: 0.4rem; }
.section-title p { color: var(--text-light); }

/* ——— HOME PAGE ——— */
.home-hero {
    background: linear-gradient(145deg, #1F4E79 0%, #2E75B6 60%, #4A90D9 100%);
    color: var(--white);
    padding: 5rem 2rem 4.5rem;
    text-align: center;
}
.home-hero__inner { max-width: 740px; margin: 0 auto; }
.home-hero__eyebrow {
    font-size: 0.75rem;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    opacity: 0.65;
    margin-bottom: 1.75rem;
}
.home-hero__title {
    font-size: 2.9rem;
    font-weight: 800;
    color: var(--white);
    border: none;
    padding: 0;
    margin: 0 0 1.6rem;
    line-height: 1.2;
    text-shadow: 0 2px 12px rgba(0,0,0,0.22);
}
.home-hero__subtitle {
    font-size: 1rem;
    line-height: 1.75;
    color: rgba(255,255,255,0.88);
    max-width: 580px;
    margin: 0 auto 2.8rem;
}
.home-hero__btn {
    display: inline-block;
    background: var(--accent);
    color: var(--primary-dark);
    padding: 0.8rem 2.2rem;
    border-radius: var(--radius);
    text-decoration: none;
    font-weight: 700;
    font-size: 1rem;
    letter-spacing: 0.01em;
    transition: background 0.2s, transform 0.2s, box-shadow 0.2s;
    box-shadow: 0 4px 14px rgba(0,0,0,0.18);
}
.home-hero__btn:hover {
    background: #d09000;
    transform: translateY(-2px);
    box-shadow: 0 6px 18px rgba(0,0,0,0.22);
}

.home-body {
    max-width: 940px;
    margin: 0 auto;
    padding: 4rem 2rem 4.5rem;
}
.home-body__inner {
    display: flex;
    gap: 3.5rem;
    align-items: flex-start;
    margin-bottom: 3rem;
}
.home-body__text { flex: 1; }
.home-body__text p {
    margin-bottom: 1.3rem;
    font-size: 1.02rem;
    line-height: 1.78;
    color: var(--text-dark);
}
.home-body__text p:last-child { margin-bottom: 0; }

.home-body__aside {
    flex-shrink: 0;
    display: flex;
    flex-direction: column;
    gap: 1rem;
    padding-top: 0.25rem;
}
.home-stat {
    background: var(--bg-light);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 1.2rem 1.6rem;
    text-align: center;
    min-width: 140px;
    transition: box-shadow 0.2s;
}
.home-stat:hover { box-shadow: var(--shadow); }
.home-stat__num {
    display: block;
    font-size: 2.4rem;
    font-weight: 800;
    color: var(--primary-dark);
    line-height: 1;
    margin-bottom: 0.4rem;
}
.home-stat__label {
    font-size: 0.72rem;
    color: var(--text-light);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    font-weight: 600;
}

.home-body__cta {
    display: flex;
    gap: 1rem;
    align-items: center;
    flex-wrap: wrap;
}
.btn-outline {
    display: inline-block;
    padding: 0.6rem 1.3rem;
    border-radius: var(--radius);
    text-decoration: none;
    font-weight: 600;
    border: 1.5px solid var(--primary-dark);
    color: var(--primary-dark);
    transition: background 0.2s, color 0.2s;
}
.btn-outline:hover { background: var(--bg-light); }

/* Home responsive */
@media (max-width: 768px) {
    .home-hero { padding: 3.5rem 1.5rem 3rem; }
    .home-hero__title { font-size: 2rem; }
    .home-body { padding: 2.5rem 1.25rem 3rem; }
    .home-body__inner { flex-direction: column; gap: 2rem; }
    .home-body__aside { flex-direction: row; flex-wrap: wrap; }
    .home-stat { flex: 1; min-width: 120px; }
}
@media (max-width: 480px) {
    .home-hero__title { font-size: 1.65rem; }
    .home-hero { padding: 2.5rem 1rem 2.5rem; }
    .home-body { padding: 2rem 1rem 2.5rem; }
}

.modules-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.25rem;
}
.module-card {
    background: var(--white);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    overflow: hidden;
    transition: transform 0.25s, box-shadow 0.25s;
    text-decoration: none;
    color: inherit;
    display: block;
}
.module-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.module-card-header {
    background: linear-gradient(135deg, var(--primary-dark), var(--primary-medium));
    color: var(--white);
    padding: 1.25rem;
    position: relative;
}
.module-card-number {
    position: absolute;
    top: 0.9rem;
    right: 0.9rem;
    background: rgba(255,255,255,0.2);
    padding: 0.2rem 0.6rem;
    border-radius: 12px;
    font-size: 0.8rem;
}
.module-card-icon { font-size: 2rem; margin-bottom: 0.4rem; }
.module-card-title { font-size: 1.1rem; font-weight: 600; }
.module-card-body { padding: 1.1rem; }
.module-card-description { color: var(--text-light); margin-bottom: 0.8rem; font-size: 0.88rem; }
.module-card-topics { display: flex; flex-wrap: wrap; gap: 0.35rem; }
.topic-tag {
    background: var(--bg-light);
    color: var(--primary-dark);
    padding: 0.15rem 0.55rem;
    border-radius: 10px;
    font-size: 0.75rem;
}

/* ——— INDEX: FOOTER ——— */
.footer {
    background: var(--primary-dark);
    color: var(--white);
    padding: 2rem;
    margin-top: 3rem;
}
.footer-container {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
}
.footer-section h3 { margin-bottom: 0.75rem; color: var(--accent); font-size: 1rem; }
.footer-section p,
.footer-section a {
    color: rgba(255,255,255,0.75);
    text-decoration: none;
    line-height: 1.8;
    display: block;
}
.footer-section a:hover { color: var(--accent); }
.footer-credit {
    font-size: 0.78rem;
    color: rgba(255,255,255,0.4) !important;
    margin-top: 0.5rem;
    letter-spacing: 0.02em;
    display: flex !important;
    align-items: center;
    justify-content: center;
    gap: 0.3rem;
}
.footer-claude-logo {
    width: 14px;
    height: 14px;
    vertical-align: middle;
    border-radius: 3px;
    opacity: 0.6;
}
.footer-bottom {
    text-align: center;
    padding-top: 1.25rem;
    margin-top: 1.25rem;
    border-top: 1px solid rgba(255,255,255,0.15);
    color: rgba(255,255,255,0.55);
    font-size: 0.85rem;
}

/* ——— BUTTONS ——— */
.btn {
    display: inline-block;
    padding: 0.6rem 1.3rem;
    border-radius: var(--radius);
    text-decoration: none;
    font-weight: 600;
    transition: background 0.25s;
}
.btn-primary { background: var(--accent); color: var(--primary-dark); }
.btn-primary:hover { background: #d09000; }

/* ===========================================
   MODULE PAGE STYLES
   =========================================== */

/* ——— COVER PAGE ——— */
.cover-page {
    text-align: center;
    padding: 52px 20px 40px;
    margin-bottom: 36px;
    border-bottom: 2px solid var(--border);
}
.cover-page .class-label {
    font-size: 1rem;
    color: var(--primary-medium);
    letter-spacing: 0.08em;
    margin-bottom: 16px;
}
.cover-page h1 {
    font-size: 2.4em;
    color: var(--primary-dark);
    border: none;
    padding: 0;
    margin: 0 0 16px;
}
.cover-page .subtitle {
    font-size: 1.2em;
    font-style: italic;
    color: var(--text-light);
}

/* ——— HEADINGS ——— */
h1 {
    color: var(--primary-dark);
    font-size: 1.55em;
    border-bottom: 2px solid var(--primary-dark);
    padding-bottom: 8px;
    margin-top: 48px;
}
h2 {
    color: var(--primary-medium);
    font-size: 1.25em;
    margin-top: 28px;
}
h3 {
    color: var(--primary-light);
    font-size: 1.1em;
    margin-top: 18px;
}

/* ——— BLOCKQUOTE ——— */
blockquote {
    background: var(--bg-light);
    border-left: 4px solid var(--primary-medium);
    margin: 18px 0;
    padding: 14px 20px;
    font-style: italic;
    color: #555;
}
blockquote p { margin: 0; }

/* ——— FEYNMAN QUOTE — citat cu atribuire vizibilă ——— */
.feynman-quote {
    position: relative;
    background: linear-gradient(180deg, #FFFBF0 0%, #FFF6E0 100%);
    border-left: 5px solid var(--accent);
    border-radius: 0 8px 8px 0;
    margin: 22px 0;
    padding: 22px 28px 18px 56px;
    font-style: italic;
    color: #3D3D3D;
    font-size: 1.02em;
    line-height: 1.6;
    box-shadow: 0 1px 3px rgba(31, 78, 121, 0.06);
}
.feynman-quote::before {
    content: "\201E";
    position: absolute;
    left: 14px;
    top: 4px;
    font-size: 3.4rem;
    font-style: normal;
    line-height: 1;
    color: var(--accent);
    opacity: 0.55;
    font-family: Georgia, 'Times New Roman', serif;
}
.feynman-quote p {
    margin: 0;
}
.feynman-quote p + p {
    margin-top: 10px;
}
.feynman-quote footer {
    margin-top: 10px;
    padding-top: 8px;
    border-top: 1px dashed rgba(31, 78, 121, 0.2);
    font-style: normal;
    font-size: 0.85em;
    color: var(--primary-dark);
    font-weight: 600;
    text-align: right;
}
.feynman-quote footer em {
    font-style: italic;
    font-weight: 400;
    color: #6C757D;
}

/* ——— TABLES ——— */
table {
    width: 100%;
    border-collapse: collapse;
    margin: 18px 0;
    font-size: 0.93em;
}
th, td {
    border: 1px solid var(--border);
    padding: 10px 14px;
    text-align: left;
}
th {
    background: var(--primary-dark);
    color: var(--white);
    font-weight: 600;
}
tr:nth-child(even) { background: #f4f6f8; }
tr:hover { background: #e8f1fa; }

/* ——— FORMULA BOXES ——— */
.formula-box {
    background: #fffbec;
    border: 1px solid #e8a000;
    border-radius: var(--radius);
    padding: 14px 20px;
    margin: 18px 0;
    text-align: center;
    font-family: 'Cambria Math', 'Georgia', serif;
    font-size: 1.15em;
}
.formula {
    font-family: 'Cambria Math', 'Georgia', serif;
    font-size: 1.05em;
    background: #fffde7;
    padding: 2px 7px;
    border-radius: 3px;
}

/* Fraction display */
.fraction {
    display: inline-flex;
    flex-direction: column;
    align-items: center;
    vertical-align: middle;
    font-size: 0.95em;
    line-height: 1.1;
}
.fraction .num {
    border-bottom: 1px solid currentColor;
    padding: 0 4px 1px;
}
.fraction .den { padding: 1px 4px 0; }

/* ——— INFO BOX ——— */
.info-box {
    background: #EBF4FB;
    border-left: 4px solid var(--primary-medium);
    padding: 13px 18px;
    margin: 18px 0;
    border-radius: 0 var(--radius) var(--radius) 0;
}
.info-box strong { color: var(--primary-dark); }

/* ——— EXPERIMENT BOX ——— */
.experiment {
    background: #EDF7EE;
    border: 1px solid #81C784;
    border-radius: var(--radius);
    padding: 18px 20px;
    margin: 24px 0;
}
.experiment h3 { color: #2E7D32; margin-top: 0; font-style: normal; }

/* ——— ANSWER BOX ——— */
.answer {
    background: #FFF8EC;
    border-left: 4px solid var(--accent);
    padding: 10px 15px;
    margin: 10px 0;
    font-style: italic;
    border-radius: 0 var(--radius) var(--radius) 0;
}

/* ——— SOLUTION BOX ——— */
.solution {
    background: #F9F2FF;
    border: 1px solid #B39DDB;
    border-radius: var(--radius);
    padding: 14px 18px;
    margin: 14px 0;
}
.solution h4 { color: #6A1B9A; margin-top: 0; }

/* ——— RESULT ——— */
.result {
    background: #C8E6C9;
    padding: 9px 14px;
    border-radius: var(--radius);
    font-weight: 600;
    text-align: center;
    margin: 14px 0;
}

/* ——— SYNTHESIS CARD ——— */
.synthesis {
    background: var(--primary-dark);
    color: var(--white);
    padding: 24px;
    border-radius: 8px;
    margin: 32px 0;
}
.synthesis h2 {
    color: var(--white);
    border-bottom: 1px solid rgba(255,255,255,0.3);
    padding-bottom: 8px;
    margin-top: 0;
}
.synthesis h3 { color: #BBDEFB; font-style: normal; margin-top: 16px; }
.synthesis table { background: var(--white); color: var(--text-dark); }
.synthesis .formula-box { background: rgba(255,255,255,0.92); color: var(--text-dark); }
.synthesis strong { color: var(--white); }

/* ——— LISTS ——— */
ul, ol { margin: 12px 0; padding-left: 22px; }
li { margin: 6px 0; }
strong { color: var(--primary-dark); }

/* ——— BREADCRUMB ——— */
.breadcrumb {
    background: var(--bg-light);
    padding: 8px 14px;
    border-radius: var(--radius);
    margin-bottom: 16px;
    font-size: 0.88em;
}
.breadcrumb a { color: var(--primary-medium); text-decoration: none; }
.breadcrumb a:hover { text-decoration: underline; }

/* ——— MODULE NAVIGATION ——— */
.module-nav {
    display: flex;
    justify-content: space-between;
    margin-top: 40px;
    padding-top: 18px;
    border-top: 1px solid var(--border);
}
.module-nav a {
    display: inline-block;
    padding: 8px 18px;
    background: var(--primary-medium);
    color: var(--white);
    text-decoration: none;
    border-radius: var(--radius);
    font-size: 0.9em;
    transition: background 0.2s;
}
.module-nav a:hover { background: var(--primary-dark); }
.module-nav a.disabled { background: #ccc; pointer-events: none; }

/* ——— MODULE FOOTER ——— */
footer {
    text-align: center;
    margin-top: 48px;
    padding: 18px 0;
    border-top: 1px solid var(--border);
    color: var(--text-light);
    font-size: 0.88em;
}
footer em { font-style: italic; }

/* ——— PRINT ——— */
@media print {
    body { max-width: 100%; }
    .hero, .module-nav, footer { display: none; }
    .cover-page { page-break-after: always; }
    h1 { page-break-before: always; }
    .cover-page h1 { page-break-before: avoid; }
}

/* ——— RESPONSIVE ——— */
@media (max-width: 768px) {
    .hero h1 { font-size: 1.7rem; }
    .modules-grid { grid-template-columns: 1fr; }
    .navbar-nav { display: none; }
}
@media (max-width: 480px) {
    .module-page { padding: 0 14px 32px; }
    .cover-page h1 { font-size: 1.8em; }
}

/* ——— BIOGRAPHY PAGE STYLES ——— */
.biography-content {
    max-width: 800px;
    margin: 0 auto;
}

.biography-section {
    margin-bottom: 2.5rem;
    padding: 1.5rem;
    background: var(--bg-light);
    border-radius: var(--radius);
    border-left: 4px solid var(--primary-medium);
}

.biography-section h3 {
    color: var(--primary-dark);
    font-size: 1.3rem;
    margin-bottom: 1rem;
    margin-top: 0;
    border: none;
    padding: 0;
}

.biography-section p {
    margin-bottom: 1rem;
    line-height: 1.7;
}

.biography-section ul {
    margin: 1rem 0;
    padding-left: 1.5rem;
}

.biography-section li {
    margin-bottom: 0.5rem;
    line-height: 1.6;
}

.biography-section strong {
    color: var(--primary-dark);
    font-weight: 600;
}