:root {
    --c-soil: #131415;
    --c-card-bg: #1c1e20;
    --c-trunk: #ffffff;
    --c-branch: #a0a0a0;
    --c-life: #1ad46d;
    --f-tech: "Inter", "Helvetica Neue", "PingFang SC", "Microsoft YaHei", sans-serif;
    --transition-growth: all 0.6s cubic-bezier(0.34, 1.56, 0.64, 1);
}

* { margin: 0; padding: 0; box-sizing: border-box; }
body { background-color: var(--c-soil); color: var(--c-trunk); font-family: var(--f-tech); overflow-x: hidden; line-height: 1.8; }

nav {
    position: fixed; top: 0; width: 100%; padding: 1.5rem 4rem; display: flex; justify-content: space-between; align-items: center; z-index: 100;
    background: rgba(19, 20, 21, 0.85); backdrop-filter: blur(12px); border-bottom: 1px solid rgba(255,255,255,0.05);
}

.logo {
    font-weight: 900;
    font-size: 1.8rem;
    letter-spacing: 4px;
    color: var(--c-life);
}

.menu { display: flex; gap: 3rem; list-style: none; }
.menu a { color: var(--c-trunk); text-decoration: none; font-size: 0.9rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.05em; opacity: 0.7; transition: all 0.3s; position: relative; }
.menu a:hover { opacity: 1; color: var(--c-life); }
.menu a::after { content: ''; position: absolute; bottom: -5px; left: 0; width: 0; height: 3px; background: var(--c-life); transition: width 0.3s ease; }
.menu a:hover::after { width: 100%; }

section { min-height: 100vh; padding: 6rem 10vw; display: flex; flex-direction: column; justify-content: center; position: relative; }
h2 { font-weight: 900; font-size: 3.5rem; margin-bottom: 3rem; position: relative; display: inline-block; letter-spacing: -1px; color: #fff; }
h2::before { content: ''; position: absolute; left: -1.5rem; top: 50%; transform: translateY(-50%); width: 6px; height: 40px; background-color: var(--c-life); }
.grow-element { opacity: 0; transform: translateY(40px) scale(0.98); transition: var(--transition-growth); }
.grow-element.rooted { opacity: 1; transform: translateY(0) scale(1); }

#home { align-items: center; text-align: center; overflow: hidden; }
#tree-canvas { position: absolute; bottom: 0; left: 50%; transform: translateX(-50%); z-index: 0; opacity: 0.7; mask-image: linear-gradient(to top, black 85%, transparent 100%); -webkit-mask-image: linear-gradient(to top, black 85%, transparent 100%); }
.hero-text { z-index: 1; position: relative; }
.hero-title { font-weight: 900; font-size: 5rem; margin-bottom: 1.5rem; letter-spacing: -2px; line-height: 1.1; }
.highlight { color: var(--c-life); }
.hero-subtitle { font-size: 1.2rem; color: var(--c-branch); max-width: 700px; margin: 0 auto; font-weight: 500; }
.scroll-hint { position: absolute; bottom: 3rem; font-size: 0.9rem; font-weight: 700; color: var(--c-life); animation: pulse-fast 2s infinite; letter-spacing: 2px; }
@keyframes pulse-fast { 0%, 100% { opacity: 0.4; transform: translateY(0); } 50% { opacity: 1; transform: translateY(10px); } }

#trunk { background: linear-gradient(to bottom, var(--c-soil), #18191a); }
.philosophy-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 2rem; margin-top: 3rem; }
.philo-card { border-left: 4px solid #333; padding: 2.5rem; transition: all 0.3s; background: var(--c-card-bg); }
.philo-card:hover { border-left-color: var(--c-life); transform: translateX(8px); background: #232528; }
.philo-title { font-weight: 900; font-size: 1.6rem; margin-bottom: 1rem; color: #fff; }
.philo-desc { color: #bbb; margin-bottom: 1.5rem; }
.philo-expand { font-weight: 700; color: var(--c-life); cursor: pointer; font-size: 0.9rem; display: inline-block; border-bottom: 1px solid transparent; }
.philo-expand:hover { border-bottom-color: var(--c-life); }
.philo-hidden-content { max-height: 0; overflow: hidden; transition: max-height 0.4s ease; font-size: 0.9rem; color: #888; margin-top: 1rem; padding-left: 1rem; border-left: 1px solid #444; }

.rhizome-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(320px, 1fr)); gap: 2rem; }
.branch-node { padding: 2.5rem; background: var(--c-card-bg); border: 1px solid rgba(255,255,255,0.05); transition: all 0.4s cubic-bezier(0.25, 1, 0.5, 1); }
.branch-node:hover { transform: translateY(-10px); border-top: 4px solid var(--c-life); box-shadow: 0 20px 40px rgba(0,0,0,0.4); }
.branch-type { font-weight: 700; color: var(--c-life); font-size: 0.8rem; margin-bottom: 0.5rem; letter-spacing: 1px; }
.branch-node h3 { font-weight: 900; font-size: 1.8rem; margin-bottom: 1rem; }
.branch-text { color: #999; }

.timeline-axis { width: 3px; background: linear-gradient(to bottom, transparent, var(--c-life), transparent); margin-right: 4rem; }
.ring-entry { margin-bottom: 5rem; position: relative; }
.ring-year { font-weight: 900; font-size: 4rem; opacity: 0.15; color: #fff; position: absolute; left: -4.5rem; top: -2rem; z-index: -1; }
.ring-content h3 { font-weight: 800; font-size: 1.5rem; margin-bottom: 0.5rem; }

.fruit-forest { display: flex; flex-wrap: wrap; gap: 2rem; }
.fruit-leaf { flex: 1 1 300px; height: 220px; background: var(--c-card-bg); border: 1px solid rgba(255,255,255,0.05); display: flex; align-items: center; justify-content: center; cursor: pointer; transition: all 0.3s; }
.fruit-leaf:hover { background: #25282b; border-color: var(--c-life); transform: scale(1.03); }
.fruit-info { text-align: center; padding: 2rem; }
.fruit-value { color: var(--c-life); font-size: 2.2rem; font-weight: 900; display: block; margin-bottom: 0.5rem; }
.fruit-name { font-weight: 700; color: #fff; }
.fruit-modal { max-width: 90vw; max-height: 80vh; padding: 3rem; border: 2px solid var(--c-life); background: var(--c-soil); box-shadow: 0 0 40px rgba(0,0,0,0.5); overflow-y: auto; }
.fruit-overlay { position: fixed; top: 0; left: 0; width: 100%; height: 100%; background: rgba(0,0,0,0.9); z-index: 1000; display: flex; justify-content: center; align-items: center; opacity: 0; pointer-events: none; transition: opacity 0.4s; }
.fruit-overlay.active { opacity: 1; pointer-events: all; }

#seeds { text-align: center; }
.seed-question-container { max-width: 800px; margin: 0 auto; }
.question-text { font-weight: 900; font-size: 2.2rem; margin-bottom: 3rem; color: #fff; }
.options-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 1.5rem; }
.option-btn { background-color: var(--c-card-bg); color: #ffffff; border: 1px solid #333; font-weight: 600; padding: 1.8rem; cursor: pointer; font-family: var(--f-tech); font-size: 1rem; transition: all 0.2s ease-in-out; border-radius: 4px; }
.option-btn:hover { border-color: var(--c-life); color: var(--c-life); background-color: #25282b; }
.option-btn.selected { background-color: var(--c-life); color: var(--c-soil); border-color: var(--c-life); font-weight: 800; transform: scale(1.02); box-shadow: 0 0 20px rgba(26, 212, 109, 0.2); }
.contact-reveal { margin-top: 4rem; opacity: 0; transform: translateY(20px); transition: all 0.5s ease; pointer-events: none; background: var(--c-card-bg); padding: 3rem; border-top: 4px solid var(--c-life); }
.contact-reveal.visible { opacity: 1; transform: translateY(0); pointer-events: all; }
.email-link { font-size: 2.5rem; font-weight: 900; color: var(--c-life); text-decoration: none; display: block; margin: 1rem 0; transition: opacity 0.3s; }
.email-link:hover { opacity: 0.8; }
footer { padding: 3rem; text-align: center; color: #555; font-size: 0.8rem; border-top: 1px solid #222; font-weight: 600; }

@media (max-width: 768px) {
    nav { padding: 1rem 1.5rem; }
    .menu { display: none; }
    
    section { padding: 4rem 1.5rem; min-height: auto; }
    
    h2 { font-size: 1.8rem; margin-bottom: 2rem; }
    h2::before { width: 4px; height: 28px; left: -0.8rem; }
    
    .hero-title { font-size: 2.2rem; letter-spacing: -1px; margin-bottom: 1rem; }
    .hero-subtitle { font-size: 1rem; padding: 0 0.5rem; }
    .scroll-hint { font-size: 0.8rem; bottom: 2rem; }
    
    .philosophy-grid { grid-template-columns: 1fr; gap: 1.2rem; margin-top: 2rem; }
    .philo-card { padding: 1.5rem; border-left-width: 3px; }
    .philo-title { font-size: 1.3rem; margin-bottom: 0.8rem; }
    .philo-desc { font-size: 0.95rem; margin-bottom: 1rem; }
    .philo-hidden-content { font-size: 0.85rem; }
    
    .rhizome-grid { grid-template-columns: 1fr; gap: 1.2rem; }
    .branch-node { padding: 1.5rem; }
    .branch-node h3 { font-size: 1.4rem; }
    .branch-text { font-size: 0.95rem; }
    
    .timeline-container { flex-direction: column; }
    .timeline-axis { width: 100%; height: 2px; margin-right: 0; margin-bottom: 2rem; background: linear-gradient(to right, transparent, var(--c-life), transparent); }
    .ring-entry { margin-bottom: 3rem; padding-left: 0; }
    .ring-year { position: static; font-size: 2.5rem; margin-bottom: 0.5rem; display: block; }
    .ring-content h3 { font-size: 1.2rem; }
    
    .fruit-forest { gap: 1rem; }
    .fruit-leaf { flex: 1 1 100%; height: auto; min-height: 160px; }
    .fruit-info { padding: 1.5rem; }
    .fruit-value { font-size: 1.6rem; }
    .fruit-name { font-size: 0.95rem; }
    
    .fruit-modal { padding: 1.5rem; max-width: 95vw; }
    .fruit-modal h3 { font-size: 1.5rem; }
    
    .question-text { font-size: 1.4rem; margin-bottom: 2rem; }
    .options-grid { grid-template-columns: 1fr; gap: 1rem; }
    .option-btn { padding: 1.2rem 1rem; font-size: 0.9rem; }
    
    .contact-reveal { padding: 1.5rem; margin-top: 2rem; }
    .email-link { font-size: 1.4rem; word-break: break-all; }
    
    footer { padding: 2rem 1rem; }
}

@media (max-width: 480px) {
    section { padding: 3rem 1rem; }
    h2 { font-size: 1.5rem; }
    .hero-title { font-size: 1.8rem; }
    .hero-subtitle { font-size: 0.9rem; }
    .philo-title { font-size: 1.2rem; }
    .branch-node h3 { font-size: 1.2rem; }
    .question-text { font-size: 1.2rem; }
    .fruit-value { font-size: 1.4rem; }
}