/* ===== Reset & Base ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
:root {
  --pri: #0e7490;
  --pri-light: #0891b2;
  --pri-pale: #ecfeff;
  --gold: #d4a017; --gold-light: #f1c40f;
  --dark: #1a202c; --mid: #4a5568; --muted: #718096;
  --border: #e2e8f0; --bg: #f7f8fc; --white: #ffffff;
  --green: #27ae60; --blue: #2980b9; --purple: #8e44ad;
  --orange: #e67e22; --teal: #16a085; --red: #c0392b;
  --radius: 12px;
  --shadow: 0 2px 16px rgba(0,0,0,0.08);
  --shadow-lg: 0 8px 32px rgba(0,0,0,0.12);
}
html { scroll-behavior: smooth; font-size: 16px; }
body { font-family: 'Noto Sans SC','PingFang SC','Microsoft YaHei','Helvetica Neue',sans-serif; background: var(--bg); color: var(--dark); line-height: 1.7; }
h1,h2,h3,h4 { font-weight:700; line-height:1.3; }
h1 { font-size: clamp(1.8rem,4vw,2.8rem); }
h2 { font-size: clamp(1.4rem,3vw,2rem); }
h3 { font-size: clamp(1.1rem,2vw,1.35rem); }
h4 { font-size:1.05rem; }
p { margin-bottom:0.8rem; }
/* Navbar */
.navbar { position:sticky; top:0; z-index:100; background:var(--white); border-bottom:2px solid var(--pri); box-shadow:var(--shadow); }
.nav-inner { max-width:1200px; margin:0 auto; padding:0 1.5rem; display:flex; align-items:center; justify-content:space-between; height:60px; }
.nav-logo { font-size:1.15rem; font-weight:800; color:var(--pri); text-decoration:none; display:flex; align-items:center; gap:0.5rem; }
.nav-logo img { width:32px; height:32px; object-fit:contain; border-radius:6px; }
.nav-links { display:flex; gap:0.25rem; list-style:none; flex-wrap:wrap; }
.nav-links a { text-decoration:none; color:var(--mid); font-size:0.88rem; font-weight:500; padding:0.4rem 0.7rem; border-radius:6px; transition:all 0.2s; }
.nav-links a:hover { background:var(--pri-pale); color:var(--pri); }
.nav-toggle { display:none; background:none; border:none; cursor:pointer; font-size:1.5rem; color:var(--dark); }
/* Progress */
.progress-bar { position:fixed; top:0; left:0; height:3px; background:linear-gradient(90deg,var(--pri),var(--gold)); width:0%; z-index:200; transition:width 0.1s; }
/* Hero */
.hero { background:linear-gradient(135deg,#052e3f 0%,#0c4a6e 40%,#0e7490 100%); color:white; padding:5rem 1.5rem 4rem; text-align:center; position:relative; overflow:hidden; }
.hero::before { content:''; position:absolute; top:-50px; right:-50px; width:300px; height:300px; background:rgba(255,255,255,0.04); border-radius:50%; }
.hero::after { content:''; position:absolute; bottom:-80px; left:-80px; width:400px; height:400px; background:rgba(255,255,255,0.03); border-radius:50%; }
.hero-badge { display:inline-block; background:rgba(255,255,255,0.15); backdrop-filter:blur(10px); border:1px solid rgba(255,255,255,0.25); color:#ffd700; font-size:0.82rem; font-weight:600; padding:0.35rem 1rem; border-radius:50px; margin-bottom:1.2rem; letter-spacing:1px; text-transform:uppercase; }
.hero h1 { color:white; margin-bottom:1rem; }
.hero-sub { font-size:1.1rem; color:rgba(255,255,255,0.8); margin-bottom:2.5rem; max-width:600px; margin-left:auto; margin-right:auto; }
.hero-stats { display:flex; justify-content:center; gap:2rem; flex-wrap:wrap; margin-bottom:2.5rem; }
.hero-stat { background:rgba(255,255,255,0.12); backdrop-filter:blur(8px); border:1px solid rgba(255,255,255,0.2); border-radius:var(--radius); padding:1rem 1.5rem; text-align:center; min-width:100px; }
.hero-stat-num { font-size:2rem; font-weight:800; color:#ffd700; display:block; }
.hero-stat-label { font-size:0.8rem; color:rgba(255,255,255,0.75); }
.hero-btns { display:flex; gap:1rem; justify-content:center; flex-wrap:wrap; }
.btn { display:inline-block; padding:0.75rem 1.8rem; border-radius:50px; font-size:0.95rem; font-weight:600; text-decoration:none; transition:all 0.25s; cursor:pointer; border:none; }
.btn-primary { background:#ffd700; color:#052e3f; }
.btn-primary:hover { background:white; transform:translateY(-2px); box-shadow:0 6px 20px rgba(0,0,0,0.25); }
.btn-outline { background:transparent; color:white; border:2px solid rgba(255,255,255,0.6); }
.btn-outline:hover { background:rgba(255,255,255,0.15); transform:translateY(-2px); }
/* Section */
.section { padding:4rem 1.5rem; }
.section-alt { background:white; }
.container { max-width:1100px; margin:0 auto; }
.section-header { text-align:center; margin-bottom:3rem; }
.section-tag { display:inline-block; background:var(--pri-pale); color:var(--pri); font-size:0.78rem; font-weight:700; padding:0.3rem 0.9rem; border-radius:50px; text-transform:uppercase; letter-spacing:1px; margin-bottom:0.75rem; }
.section-header h2 { color:var(--dark); margin-bottom:0.5rem; }
.section-header p { color:var(--muted); font-size:1.05rem; max-width:580px; margin:0 auto; }
/* Cards */
.cards-grid { display:grid; grid-template-columns:repeat(auto-fit,minmax(260px,1fr)); gap:1.5rem; }
.card { background:white; border-radius:var(--radius); padding:1.8rem; box-shadow:var(--shadow); border:1px solid var(--border); transition:transform 0.2s,box-shadow 0.2s; }
.card:hover { transform:translateY(-4px); box-shadow:var(--shadow-lg); }
.card-icon { font-size:2.2rem; margin-bottom:1rem; }
.card h3 { margin-bottom:0.5rem; color:var(--dark); }
.card p { color:var(--muted); font-size:0.93rem; margin:0; }
/* Stats Banner */
.stats-banner { background:linear-gradient(135deg,#1a202c,#2d3748); color:white; padding:3rem 1.5rem; }
.stats-banner .container { display:grid; grid-template-columns:repeat(auto-fit,minmax(150px,1fr)); gap:2rem; }
.stat-item { text-align:center; }
.stat-num { font-size:2.2rem; font-weight:800; color:#ffd700; display:block; }
.stat-label { font-size:0.85rem; color:rgba(255,255,255,0.7); margin-top:0.2rem; }
/* Format */
.format-grid { display:grid; grid-template-columns:1fr 1fr; gap:2rem; }
.format-card { background:white; border-radius:var(--radius); overflow:hidden; box-shadow:var(--shadow); border:1px solid var(--border); }
.format-header { padding:1.2rem 1.5rem; display:flex; align-items:center; gap:1rem; }
.format-header.reading { background:linear-gradient(135deg,#2980b9,#1a6fa8); color:white; }
.format-header.video { background:linear-gradient(135deg,#0e7490,#0c4a6e); color:white; }
.format-header-icon { font-size:2rem; }
.format-header-info h3 { color:white; font-size:1.1rem; }
.format-header-info span { color:rgba(255,255,255,0.8); font-size:0.85rem; }
.format-body { padding:1.5rem; }
.format-body ul { list-style:none; }
.format-body li { padding:0.5rem 0; border-bottom:1px solid var(--border); display:flex; align-items:flex-start; gap:0.7rem; font-size:0.93rem; color:var(--mid); }
.format-body li:last-child { border-bottom:none; }
.format-body li::before { content:'✓'; color:var(--green); font-weight:700; flex-shrink:0; margin-top:0.1rem; }
/* Marks bar */
.marks-bar { background:#f0f4f8; border-radius:var(--radius); padding:1.5rem; margin:2rem 0; }
.marks-row { display:flex; align-items:center; gap:1rem; margin-bottom:1rem; }
.marks-row:last-child { margin-bottom:0; }
.marks-label { font-size:0.88rem; font-weight:600; color:var(--dark); min-width:120px; }
.marks-track { flex:1; background:#dde3ea; border-radius:50px; height:12px; overflow:hidden; }
.marks-fill { height:100%; border-radius:50px; }
.marks-fill.blue { background:linear-gradient(90deg,#2980b9,#3498db); }
.marks-fill.teal { background:linear-gradient(90deg,#0e7490,#0891b2); }
.marks-fill.green { background:linear-gradient(90deg,#27ae60,#2ecc71); }
.marks-num { font-weight:700; color:var(--dark); font-size:0.9rem; min-width:60px; text-align:right; }
/* Timeline */
.timeline { position:relative; padding-left:2rem; }
.timeline::before { content:''; position:absolute; left:0.6rem; top:0; bottom:0; width:3px; background:linear-gradient(to bottom,var(--pri),var(--gold)); border-radius:2px; }
.timeline-item { position:relative; padding:0 0 2rem 2rem; }
.timeline-dot { position:absolute; left:-1.95rem; top:0.25rem; width:1.3rem; height:1.3rem; border-radius:50%; background:white; border:3px solid var(--pri); display:flex; align-items:center; justify-content:center; font-size:0.6rem; font-weight:700; color:var(--pri); }
.timeline-content { background:white; border-radius:var(--radius); padding:1.2rem 1.5rem; box-shadow:var(--shadow); border:1px solid var(--border); }
.timeline-time { display:inline-block; background:var(--pri-pale); color:var(--pri); font-size:0.75rem; font-weight:700; padding:0.2rem 0.6rem; border-radius:50px; margin-bottom:0.5rem; }
.timeline-content h4 { margin-bottom:0.4rem; }
.timeline-content p { margin:0; color:var(--muted); font-size:0.9rem; }
/* Accordion */
.topic-grid { display:grid; grid-template-columns:repeat(auto-fill,minmax(320px,1fr)); gap:1rem; }
.accordion-item { background:white; border-radius:var(--radius); box-shadow:var(--shadow); border:1px solid var(--border); overflow:hidden; transition:box-shadow 0.2s; }
.accordion-item.open { box-shadow:var(--shadow-lg); }
.accordion-btn { width:100%; display:flex; align-items:center; gap:1rem; padding:1.1rem 1.3rem; background:none; border:none; cursor:pointer; text-align:left; transition:background 0.2s; }
.accordion-btn:hover { background:#fafafa; }
.accordion-icon { font-size:1.6rem; flex-shrink:0; }
.accordion-title { flex:1; }
.accordion-title h4 { font-size:0.97rem; color:var(--dark); margin:0; }
.accordion-title span { font-size:0.78rem; color:var(--muted); }
.accordion-arrow { font-size:1rem; color:var(--muted); transition:transform 0.3s; flex-shrink:0; }
.accordion-item.open .accordion-arrow { transform:rotate(180deg); }
.accordion-body { display:none; padding:0 1.3rem 1.3rem; border-top:1px solid var(--border); }
.accordion-item.open .accordion-body { display:block; }
.vocab-chips { display:flex; flex-wrap:wrap; gap:0.4rem; margin:0.8rem 0; }
.chip { background:var(--pri-pale); color:var(--pri); font-size:0.8rem; font-weight:600; padding:0.25rem 0.7rem; border-radius:50px; border:1px solid rgba(14,116,144,0.2); }
.chip.blue { background:#ebf5fb; color:var(--blue); border-color:rgba(41,128,185,0.2); }
.chip.green { background:#eafaf1; color:var(--green); border-color:rgba(39,174,96,0.2); }
.chip.purple { background:#f5eef8; color:var(--purple); border-color:rgba(142,68,173,0.2); }
.chip.orange { background:#fef3e2; color:var(--orange); border-color:rgba(230,126,34,0.2); }
.sample-qa { margin-top:0.8rem; }
.sample-q { background:#f0f4f8; border-left:3px solid var(--blue); border-radius:0 8px 8px 0; padding:0.7rem 1rem; margin-bottom:0.4rem; font-size:0.88rem; color:var(--dark); font-weight:500; }
.sample-q::before { content:'❓ '; }
.sample-a { background:#f0fdf4; border-left:3px solid var(--green); border-radius:0 8px 8px 0; padding:0.7rem 1rem; margin-bottom:0.8rem; font-size:0.85rem; color:var(--mid); line-height:1.6; }
.sample-a::before { content:'💡 参考思路：'; font-weight:600; color:var(--green); display:block; margin-bottom:0.3rem; }
/* Tips */
.tips-grid { display:grid; grid-template-columns:1fr 1fr; gap:2rem; }
.tips-section { background:white; border-radius:var(--radius); padding:2rem; box-shadow:var(--shadow); border:1px solid var(--border); }
.tips-section h3 { color:var(--dark); margin-bottom:1.2rem; padding-bottom:0.8rem; border-bottom:2px solid var(--border); display:flex; align-items:center; gap:0.7rem; }
.tip-item { display:flex; gap:0.8rem; margin-bottom:1rem; align-items:flex-start; }
.tip-num { background:var(--pri); color:white; width:1.6rem; height:1.6rem; border-radius:50%; display:flex; align-items:center; justify-content:center; font-size:0.75rem; font-weight:700; flex-shrink:0; margin-top:0.1rem; }
.tip-text { font-size:0.9rem; color:var(--mid); line-height:1.6; }
.tip-text strong { color:var(--dark); }
/* PEEL box */
.peel-box { display:grid; grid-template-columns:repeat(4,1fr); gap:1rem; margin-top:1.5rem; }
.peel-item { border-radius:var(--radius); padding:1.2rem; text-align:center; }
.peel-item.P { background:linear-gradient(135deg,#0e7490,#0891b2); color:white; }
.peel-item.E1 { background:linear-gradient(135deg,#2980b9,#3498db); color:white; }
.peel-item.E2 { background:linear-gradient(135deg,#27ae60,#2ecc71); color:white; }
.peel-item.L { background:linear-gradient(135deg,#8e44ad,#9b59b6); color:white; }
.peel-letter { font-size:2.5rem; font-weight:900; display:block; opacity:0.9; }
.peel-cn { font-weight:700; font-size:1rem; display:block; margin:0.3rem 0; }
.peel-desc { font-size:0.78rem; opacity:0.85; }
/* Phrases */
.phrases-grid { display:grid; grid-template-columns:repeat(auto-fill,minmax(260px,1fr)); gap:1.5rem; }
.phrase-card { background:white; border-radius:var(--radius); padding:1.5rem; box-shadow:var(--shadow); border:1px solid var(--border); }
.phrase-card h4 { font-size:0.88rem; font-weight:700; text-transform:uppercase; letter-spacing:0.5px; margin-bottom:1rem; padding-bottom:0.6rem; border-bottom:2px solid var(--border); }
.phrase-card h4.teal { color:var(--pri); border-color:var(--pri); }
.phrase-card h4.blue { color:var(--blue); border-color:var(--blue); }
.phrase-card h4.green { color:var(--green); border-color:var(--green); }
.phrase-card h4.gold { color:var(--gold); border-color:var(--gold); }
.phrase-card h4.purple { color:var(--purple); border-color:var(--purple); }
.phrase-card h4.orange { color:var(--orange); border-color:var(--orange); }
.phrase-list { list-style:none; }
.phrase-list li { padding:0.45rem 0; border-bottom:1px dashed var(--border); font-size:0.88rem; color:var(--mid); display:flex; justify-content:space-between; align-items:center; gap:0.5rem; }
.phrase-list li:last-child { border-bottom:none; }
.phrase-cn { font-weight:600; color:var(--dark); }
.phrase-note { font-size:0.75rem; color:var(--muted); font-style:italic; }
/* Practice */
.practice-tabs { display:flex; gap:0.5rem; margin-bottom:1.5rem; flex-wrap:wrap; }
.tab-btn { padding:0.55rem 1.2rem; border-radius:50px; border:2px solid var(--border); background:white; font-size:0.88rem; font-weight:600; color:var(--mid); cursor:pointer; transition:all 0.2s; }
.tab-btn.active { background:var(--pri); border-color:var(--pri); color:white; }
.tab-btn:hover:not(.active) { border-color:var(--pri); color:var(--pri); }
.tab-content { display:none; }
.tab-content.active { display:block; }
.practice-card { background:white; border-radius:var(--radius); padding:2rem; box-shadow:var(--shadow); border:1px solid var(--border); }
.practice-scene { background:linear-gradient(135deg,#f0f9ff,#e0f2fe); border-radius:8px; padding:1.2rem; margin-bottom:1.5rem; border-left:4px solid var(--pri); }
.practice-scene h4 { color:var(--pri); font-size:0.88rem; text-transform:uppercase; margin-bottom:0.5rem; }
.practice-scene p { margin:0; color:var(--mid); font-size:0.92rem; }
.qa-item { margin-bottom:1.5rem; }
.qa-q { font-weight:700; color:var(--dark); font-size:0.95rem; margin-bottom:0.5rem; display:flex; align-items:flex-start; gap:0.5rem; }
.qa-q::before { content:'Q:'; color:var(--pri); font-size:0.85rem; margin-top:0.15rem; flex-shrink:0; }
.qa-a { background:#f9f9fb; border:1px solid var(--border); border-radius:8px; padding:1rem 1.2rem; font-size:0.88rem; color:var(--mid); line-height:1.8; }
.qa-label { font-weight:700; color:var(--green); font-size:0.78rem; display:block; margin-bottom:0.4rem; }
.highlight-phrase { background:#fff3cd; color:#856404; padding:0 3px; border-radius:3px; font-weight:600; }
/* Plan */
.plan-grid { display:grid; grid-template-columns:repeat(auto-fill,minmax(240px,1fr)); gap:1.5rem; }
.plan-card { background:white; border-radius:var(--radius); overflow:hidden; box-shadow:var(--shadow); border:1px solid var(--border); }
.plan-header { padding:1rem 1.3rem; color:white; font-weight:700; font-size:0.95rem; }
.plan-header.week1 { background:linear-gradient(135deg,#2980b9,#1a6fa8); }
.plan-header.week2 { background:linear-gradient(135deg,#8e44ad,#7d3c98); }
.plan-header.week3 { background:linear-gradient(135deg,#16a085,#117a65); }
.plan-header.week4 { background:linear-gradient(135deg,#d35400,#b7440e); }
.plan-header.exam { background:linear-gradient(135deg,#0e7490,#0c4a6e); }
.plan-body { padding:1rem 1.3rem; }
.plan-body ul { list-style:none; }
.plan-body li { display:flex; align-items:flex-start; gap:0.5rem; padding:0.3rem 0; font-size:0.87rem; color:var(--mid); }
.plan-body li::before { content:'•'; color:var(--pri); font-weight:700; flex-shrink:0; }
/* Rubric table */
.rubric-table { width:100%; border-collapse:collapse; background:white; border-radius:var(--radius); overflow:hidden; box-shadow:var(--shadow); }
.rubric-table th { background:var(--dark); color:white; padding:0.8rem 1rem; text-align:left; font-size:0.85rem; }
.rubric-table td { padding:0.75rem 1rem; border-bottom:1px solid var(--border); font-size:0.87rem; color:var(--mid); vertical-align:top; }
.rubric-table tr:last-child td { border-bottom:none; }
.rubric-table tr:nth-child(even) td { background:#fafbfc; }
/* Callout */
.callout { border-radius:var(--radius); padding:1.2rem 1.5rem; margin:1.5rem 0; display:flex; gap:1rem; align-items:flex-start; }
.callout-icon { font-size:1.4rem; flex-shrink:0; margin-top:0.1rem; }
.callout-body h4 { font-size:0.9rem; margin-bottom:0.3rem; }
.callout-body p { font-size:0.88rem; margin:0; color:var(--mid); }
.callout.warning { background:#fff8e1; border-left:4px solid #f39c12; }
.callout.warning h4 { color:#e67e22; }
.callout.info { background:#ebf5fb; border-left:4px solid #2980b9; }
.callout.info h4 { color:#2980b9; }
.callout.success { background:#eafaf1; border-left:4px solid #27ae60; }
.callout.success h4 { color:#27ae60; }
.callout.tip { background:var(--pri-pale); border-left:4px solid var(--pri); }
.callout.tip h4 { color:var(--pri); }
/* Compare table */
.compare-table { width:100%; border-collapse:collapse; background:white; border-radius:var(--radius); overflow:hidden; box-shadow:var(--shadow); margin-top:1.5rem; }
.compare-table th { background:var(--pri); color:white; padding:1rem 1.2rem; text-align:center; font-size:0.9rem; }
.compare-table th:first-child { text-align:left; }
.compare-table td { padding:0.85rem 1.2rem; border-bottom:1px solid var(--border); font-size:0.9rem; color:var(--mid); text-align:center; }
.compare-table td:first-child { text-align:left; font-weight:600; color:var(--dark); }
.compare-table tr:last-child td { border-bottom:none; }
.compare-table tr:nth-child(even) td { background:#fafbfc; }
.level-badge { display:inline-block; padding:0.2rem 0.7rem; border-radius:50px; font-size:0.75rem; font-weight:700; color:white; }
.level-hcl { background:#8e44ad; }
.level-cl { background:#0e7490; }
.level-fcl { background:#27ae60; }
/* Footer */
footer { background:#1a202c; color:rgba(255,255,255,0.65); padding:2.5rem 1.5rem 1.5rem; text-align:center; font-size:0.85rem; }
.footer-inner { max-width:900px; margin:0 auto; }
.footer-brand { display:flex; align-items:center; justify-content:center; gap:1rem; margin-bottom:1.5rem; }
.footer-logo { width:52px; height:52px; object-fit:contain; border-radius:10px; }
.footer-brand-text { text-align:left; }
.footer-brand-name { font-size:1.15rem; font-weight:800; color:#fff; }
.footer-brand-tagline { font-size:.76rem; color:rgba(255,255,255,.45); }
footer .footer-links { display:flex; justify-content:center; gap:1.5rem; margin:0 0 1.5rem; flex-wrap:wrap; }
footer .footer-links a { color:rgba(255,255,255,0.45); text-decoration:none; transition:color 0.2s; }
footer .footer-links a:hover { color:white; }
.footer-bottom { border-top:1px solid rgba(255,255,255,.1); padding-top:1.5rem; margin-top:1.5rem; }
/* Responsive */
@media(max-width:900px) {
  .tips-grid,.format-grid { grid-template-columns:1fr; }
  .peel-box { grid-template-columns:1fr 1fr; }
  .nav-links { display:none; }
  .nav-links.open { display:flex; flex-direction:column; position:absolute; top:60px; left:0; right:0; background:white; padding:1rem; border-bottom:1px solid var(--border); box-shadow:var(--shadow); z-index:99; }
  .nav-toggle { display:block; }
}
@media(max-width:600px) {
  .hero { padding:3rem 1rem 2.5rem; }
  .section { padding:2.5rem 1rem; }
  .hero-stats { gap:0.8rem; }
  .hero-stat { padding:0.7rem 1rem; }
  .peel-box { grid-template-columns:1fr 1fr; }
}