/* ============================================
   caldera.css — 破火山口专题专属样式
   ============================================ */

/* ---- Caldera Hero ---- */
.caldera-hero {
    min-height: 70vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
    background: linear-gradient(160deg, #1a0a0a 0%, #3e1c1c 40%, #5d2e2e 100%);
    padding-top: 72px;
}
.caldera-hero-canvas {
    position: absolute;
    top: 0; left: 0;
    width: 100%; height: 100%;
    z-index: 1;
}
.caldera-hero-content {
    position: relative;
    z-index: 2;
    text-align: center;
    color: white;
    max-width: 800px;
    padding: 0 var(--space-lg);
}
.caldera-hero-content h1 {
    font-family: var(--font-heading);
    font-size: clamp(2.5rem, 6vw, 4rem);
    font-weight: 900;
    line-height: 1.15;
    margin-bottom: var(--space-lg);
    text-shadow: 0 2px 20px rgba(0,0,0,0.5);
}
.caldera-hero-content p {
    font-size: clamp(1rem, 2vw, 1.25rem);
    color: rgba(255,255,255,0.75);
    line-height: 1.8;
    max-width: 640px;
    margin: 0 auto;
}

/* ---- Caldera Section Canvas ---- */
.caldera-section-canvas {
    width: 100%;
    height: 420px;
    background: linear-gradient(180deg, #1a0a0a 0%, #2e1a1a 50%, #3e2a2a 100%);
    border-radius: var(--radius-xl);
    overflow: hidden;
}

/* ---- Formation Mechanism ---- */
.formation-canvas-wrap {
    width: 100%;
    height: 380px;
    background: linear-gradient(180deg, #1a1a2e 0%, #16213e 50%, #0f3460 100%);
    border-radius: var(--radius-xl);
    overflow: hidden;
    margin-bottom: var(--space-2xl);
}
.formation-canvas-wrap canvas {
    width: 100%; height: 100%;
    display: block;
}

.formation-steps {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-xl);
}
.formation-step {
    background: var(--color-card);
    border-radius: var(--radius-xl);
    padding: var(--space-xl);
    border: 1px solid var(--color-border-light);
    transition: var(--transition-base);
    position: relative;
    overflow: hidden;
}
.formation-step::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--color-primary), var(--color-secondary));
    opacity: 0;
    transition: var(--transition-base);
}
.formation-step:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-lg);
    border-color: transparent;
}
.formation-step:hover::before { opacity: 1; }
.formation-step .step-num {
    width: 44px; height: 44px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: var(--font-heading);
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: var(--space-md);
}
.formation-step h4 {
    font-family: var(--font-heading);
    font-size: 1.0625rem;
    margin-bottom: var(--space-sm);
    color: var(--color-text);
}
.formation-step p {
    font-size: 0.875rem;
    color: var(--color-text-secondary);
    line-height: 1.7;
    margin-bottom: 0;
}

/* ---- Supereruption Section ---- */
.supereruption-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-3xl);
    align-items: start;
}
.supereruption-text h3 {
    font-family: var(--font-heading);
    font-size: 1.75rem;
    margin-bottom: var(--space-lg);
    color: var(--color-text);
}
.supereruption-text p {
    color: var(--color-text-secondary);
    line-height: 1.9;
    margin-bottom: var(--space-md);
    font-size: 1rem;
}
.climate-impact-box {
    background: var(--color-card);
    border-radius: var(--radius-xl);
    padding: var(--space-xl);
    border: 1px solid var(--color-border-light);
    margin-top: var(--space-xl);
}
.climate-impact-box h4 {
    font-family: var(--font-heading);
    font-size: 1.125rem;
    margin-bottom: var(--space-md);
    color: var(--color-text);
}
.climate-impact-box ul {
    list-style: none;
    padding: 0;
    margin: 0;
}
.climate-impact-box li {
    font-size: 0.9375rem;
    color: var(--color-text-secondary);
    line-height: 1.8;
    padding: var(--space-xs) 0;
    padding-left: var(--space-md);
    position: relative;
    border-bottom: 1px solid var(--color-border-light);
}
.climate-impact-box li:last-child { border-bottom: none; }
.climate-impact-box li::before {
    content: '▸';
    position: absolute;
    left: 0;
    color: var(--color-primary);
    font-weight: 700;
}
.climate-impact-box li strong {
    color: var(--color-text);
}

/* ---- Timeline Canvas ---- */
.timeline-canvas-wrap {
    width: 100%;
    height: 400px;
    position: relative;
}
.timeline-canvas-wrap canvas {
    width: 100%; height: 100%;
    display: block;
}

/* ---- Size Comparison Canvas ---- */
.size-canvas-wrap {
    width: 100%;
    height: 400px;
    position: relative;
}
.size-canvas-wrap canvas {
    width: 100%; height: 100%;
    display: block;
}

/* ---- VEI Chart for Caldera ---- */
#calderaVEIChart {
    width: 100%; height: 100%;
    display: block;
}

/* ---- Responsive ---- */
@media (max-width: 1023px) {
    .formation-steps { grid-template-columns: repeat(2, 1fr); }
    .supereruption-grid { grid-template-columns: 1fr; }
    .caldera-section-canvas { height: 340px; }
    .formation-canvas-wrap { height: 320px; }
    .timeline-canvas-wrap { height: 340px; }
    .size-canvas-wrap { height: 340px; }
}

@media (max-width: 767px) {
    .formation-steps { grid-template-columns: 1fr; }
    .caldera-hero { min-height: 50vh; }
    .caldera-section-canvas { height: 280px; }
    .formation-canvas-wrap { height: 260px; }
    .timeline-canvas-wrap { height: 280px; }
    .size-canvas-wrap { height: 280px; }
}