/* ============================================================
   Garden Paper Mart Academy — Shared Stylesheet
   Cambridge Additional Mathematics (4037 / 0606)
   Version 1.0 — 2026
   Primary:  Dark Teal   #00695c
   Accent:   Gold        #f9a825
   Light bg: Teal tint   #e0f2f1
   ============================================================ */

/* RESET & BASE */
* { box-sizing: border-box; margin: 0; padding: 0; }

body {
    font-family: Georgia, 'Times New Roman', serif;
    background: #f4fbfa;
    color: #1a1a1a;
    line-height: 1.75;
}

/* ── HEADER ─────────────────────────────────────────────── */
header {
    background: linear-gradient(135deg, #00695c 0%, #00897b 100%);
    color: white;
    padding: 22px 30px;
    border-bottom: 4px solid #f9a825;
}
.breadcrumb { font-size: 13px; margin-bottom: 8px; }
.breadcrumb a { color: #a7ffeb; text-decoration: none; }
.breadcrumb a:hover { text-decoration: underline; }
header h1 { font-size: 26px; font-weight: bold; }
header p.subtitle {
    color: #b2dfdb;
    font-size: 14px;
    margin-top: 6px;
}

/* ── MAIN CONTAINER ─────────────────────────────────────── */
.container { max-width: 880px; margin: 30px auto; padding: 0 20px 60px; }

/* ── SECTIONS ───────────────────────────────────────────── */
section {
    background: white;
    border-radius: 8px;
    padding: 24px 28px;
    margin-bottom: 24px;
    box-shadow: 0 1px 5px rgba(0,105,92,0.08);
    border-top: 3px solid #00695c;
}

/* ── HEADINGS ───────────────────────────────────────────── */
h2 {
    color: #00695c;
    font-size: 20px;
    margin-bottom: 14px;
    border-bottom: 2px solid #b2dfdb;
    padding-bottom: 8px;
}
h3 { color: #00695c; font-size: 17px; margin: 18px 0 10px; }
h4 { color: #00695c; margin-bottom: 6px; }

/* ── TYPOGRAPHY ─────────────────────────────────────────── */
p  { margin-bottom: 12px; }
ul, ol { margin: 10px 0 12px 22px; }
li { margin-bottom: 6px; }
strong { color: #00695c; }

/* ── TABLES ─────────────────────────────────────────────── */
table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 14px;
    font-size: 15px;
}
th {
    background: #00695c;
    color: white;
    padding: 10px 14px;
    text-align: left;
    border: 1px solid #80cbc4;
}
td {
    padding: 10px 14px;
    border: 1px solid #e0f2f1;
    vertical-align: top;
}
tr:nth-child(even) td { background: #e0f2f1; }

/* ── KEY CONCEPT BOX (teal) ─────────────────────────────── */
.key-concept {
    background: #e0f2f1;
    padding: 13px 17px;
    border-left: 5px solid #00695c;
    margin: 14px 0;
    border-radius: 0 6px 6px 0;
}
.key-concept strong { color: #00695c; }

/* ── GOLD RULE BOX ──────────────────────────────────────── */
.rule-box {
    background: #fffde7;
    padding: 13px 17px;
    border-left: 5px solid #f9a825;
    margin: 14px 0;
    border-radius: 0 6px 6px 0;
}
.rule-box strong { color: #e65100; }

/* ── FORMULA BOX ────────────────────────────────────────── */
.formula-box {
    background: #e0f2f1;
    border: 2px solid #00897b;
    border-radius: 8px;
    padding: 14px 20px;
    margin: 14px 0;
    font-size: 15px;
    text-align: center;
}
.formula-box h4 {
    color: #00695c;
    margin-bottom: 8px;
    font-size: 15px;
    text-align: left;
}
.formula-box .formula {
    font-size: 17px;
    font-weight: bold;
    color: #00695c;
    font-family: 'Courier New', monospace;
    margin: 6px 0;
}

/* ── WORKED EXAMPLE BOX ─────────────────────────────────── */
.worked-example {
    background: #f1f8e9;
    border: 1px solid #a5d6a7;
    border-radius: 8px;
    padding: 16px 20px;
    margin: 16px 0;
}
.worked-example h4 {
    color: #2e7d32;
    font-size: 15px;
    margin-bottom: 10px;
    border-bottom: 1px solid #c8e6c9;
    padding-bottom: 6px;
}
.worked-example .step {
    display: flex;
    gap: 12px;
    margin-bottom: 8px;
    font-size: 14px;
    align-items: flex-start;
}
.step-num {
    background: #00695c;
    color: white;
    border-radius: 50%;
    width: 22px;
    height: 22px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
    font-weight: bold;
    flex-shrink: 0;
    margin-top: 2px;
}
.step-content { flex: 1; line-height: 1.6; }
.step-content .math {
    font-family: 'Courier New', monospace;
    background: #e0f2f1;
    padding: 2px 8px;
    border-radius: 4px;
    font-size: 14px;
    display: inline-block;
    margin: 2px 0;
}

/* ── TIP BOX ────────────────────────────────────────────── */
.tip-box {
    background: #fff8e1;
    padding: 13px 17px;
    border-left: 5px solid #f9a825;
    margin: 14px 0;
    border-radius: 0 6px 6px 0;
    font-size: 14px;
}
.tip-box strong { color: #e65100; }

/* ── WARNING BOX ────────────────────────────────────────── */
.warn-box {
    background: #fce4ec;
    padding: 13px 17px;
    border-left: 5px solid #e91e63;
    margin: 14px 0;
    border-radius: 0 6px 6px 0;
    font-size: 14px;
}
.warn-box strong { color: #880e4f; }

/* ── PROOF BOX (distinct style for mathematical proofs) ─── */
.proof-box {
    background: #f3e5f5;
    border: 1px solid #ce93d8;
    border-radius: 8px;
    padding: 16px 20px;
    margin: 14px 0;
    font-size: 14px;
}
.proof-box h4 {
    color: #6a1b9a;
    margin-bottom: 10px;
    font-size: 15px;
}
.proof-box .math {
    font-family: 'Courier New', monospace;
    background: #ede7f6;
    padding: 2px 8px;
    border-radius: 4px;
    font-size: 14px;
    display: inline-block;
    margin: 2px 0;
}

/* ── GRID LAYOUTS ───────────────────────────────────────── */
.grid-2 {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 14px;
    margin-top: 14px;
}
.grid-3 {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: 14px;
    margin-top: 14px;
}

/* ── CARDS ──────────────────────────────────────────────── */
.card {
    background: #e0f2f1;
    border: 1px solid #80cbc4;
    border-radius: 6px;
    padding: 14px 16px;
}
.card h4 { color: #00695c; margin-bottom: 6px; font-size: 15px; }

/* Gold card — for results and theorems */
.card-gold {
    background: #fffde7;
    border: 1px solid #ffe082;
    border-radius: 6px;
    padding: 14px 16px;
}
.card-gold h4 { color: #e65100; margin-bottom: 6px; font-size: 15px; }

/* ── DIAGRAM BOX ────────────────────────────────────────── */
.diagram-box {
    background: #f4fbfa;
    border: 2px dashed #80cbc4;
    border-radius: 8px;
    padding: 18px;
    text-align: center;
    margin: 14px 0;
}

/* ── EXAM PRACTICE SECTION ──────────────────────────────── */
.quiz-section {
    background: #e0f2f1;
    padding: 24px 28px;
    border-radius: 8px;
    margin-bottom: 24px;
    border-top: 3px solid #f9a825;
}
.quiz-section h3 { color: #00695c; margin-bottom: 14px; }

.q-block {
    background: white;
    border-radius: 6px;
    padding: 16px 20px;
    margin-bottom: 16px;
    border: 1px solid #80cbc4;
}
.q-block p { margin-bottom: 6px; }

.answer {
    background: #e8f5e9;
    border-radius: 4px;
    padding: 10px 14px;
    margin-top: 10px;
    border-left: 3px solid #2e7d32;
    font-size: 14px;
}
.answer .math-ans {
    font-family: 'Courier New', monospace;
    background: #c8e6c9;
    padding: 2px 8px;
    border-radius: 4px;
    font-weight: bold;
}

.exam-tip {
    background: #fff3e0;
    border-radius: 4px;
    padding: 10px 14px;
    margin-top: 8px;
    border-left: 3px solid #f9a825;
    font-size: 13px;
}

/* ── NAVIGATION BUTTONS ─────────────────────────────────── */
.lesson-nav {
    text-align: center;
    margin-top: 10px;
    display: flex;
    justify-content: center;
    gap: 16px;
    flex-wrap: wrap;
}
.btn {
    display: inline-block;
    background: #00695c;
    color: white;
    padding: 12px 28px;
    border-radius: 6px;
    text-decoration: none;
    font-size: 15px;
}
.btn:hover { background: #004d40; }
.btn-gold {
    display: inline-block;
    background: #f9a825;
    color: #1a1a1a;
    padding: 12px 28px;
    border-radius: 6px;
    text-decoration: none;
    font-size: 15px;
    font-weight: bold;
}
.btn-gold:hover { background: #f57f17; }
.btn-outline {
    display: inline-block;
    background: white;
    color: #00695c;
    border: 2px solid #00695c;
    padding: 11px 28px;
    border-radius: 6px;
    text-decoration: none;
    font-size: 15px;
}
.btn-outline:hover { background: #e0f2f1; }

/* ── SYLLABUS REFERENCE BADGES ──────────────────────────── */
.syllabus-ref {
    display: inline-block;
    background: #00695c;
    color: white;
    font-size: 11px;
    padding: 2px 10px;
    border-radius: 20px;
    margin-left: 8px;
    vertical-align: middle;
}
.syllabus-ref-gold {
    display: inline-block;
    background: #f9a825;
    color: #1a1a1a;
    font-size: 11px;
    padding: 2px 10px;
    border-radius: 20px;
    margin-left: 8px;
    vertical-align: middle;
    font-weight: bold;
}

/* ── PROGRESS BAR ───────────────────────────────────────── */
.lesson-progress {
    background: white;
    border-radius: 8px;
    padding: 14px 20px;
    margin-bottom: 20px;
    box-shadow: 0 1px 5px rgba(0,105,92,0.08);
    display: flex;
    align-items: center;
    gap: 14px;
    flex-wrap: wrap;
    font-size: 13px;
    color: #555;
}
.progress-bar-wrap {
    flex: 1;
    background: #b2dfdb;
    border-radius: 20px;
    height: 8px;
    min-width: 120px;
}
.progress-bar-fill {
    background: linear-gradient(90deg, #00695c, #f9a825);
    height: 8px;
    border-radius: 20px;
}

/* ── PREREQUISITE BANNER ────────────────────────────────── */
.prereq-banner {
    background: #fffde7;
    border: 1px solid #ffe082;
    border-radius: 8px;
    padding: 14px 18px;
    margin-bottom: 20px;
    font-size: 14px;
    color: #5d4037;
}
.prereq-banner strong { color: #e65100; }

/* ── FOOTER ─────────────────────────────────────────────── */
footer {
    text-align: center;
    padding: 20px;
    color: #666;
    font-size: 13px;
    border-top: 1px solid #b2dfdb;
    background: white;
}

/* ── RESPONSIVE ─────────────────────────────────────────── */
@media(max-width:600px) {
    .grid-2, .grid-3 { grid-template-columns: 1fr; }
    header h1 { font-size: 20px; }
    .container { padding: 0 12px 40px; }
    .step { flex-direction: column; gap: 6px; }
}