/* ═══════════════════════════════════════════
   言葉熱度 — CSS Design System
   Aesthetic: 日系杂志 × 小红书温柔质感
   ═══════════════════════════════════════════ */
:root {
  --sakura-50:#fef7f8;--sakura-100:#fdeef0;--sakura-200:#fbd5da;--sakura-300:#f8aeba;
  --sakura-400:#f47a9a;--sakura-500:#e84d7a;--sakura-600:#d42d60;--sakura-700:#b01d4c;
  --sakura-800:#901c44;--sakura-900:#7a1b3e;
  --matcha-50:#f4f9f0;--matcha-100:#e6f2dc;--matcha-200:#cde5ba;--matcha-300:#a9d08e;
  --matcha-400:#84b862;--matcha-500:#639c42;--matcha-600:#4c7c33;
  --ink-50:#f7f7f8;--ink-100:#eeeff1;--ink-200:#d5d7dc;--ink-300:#b0b4be;
  --ink-400:#858b9a;--ink-500:#676e80;--ink-600:#51576a;--ink-700:#434858;
  --ink-800:#3a3e4c;--ink-900:#1d1f28;
  --bg-primary:#fef9f7;--bg-secondary:#fff5f2;--bg-card:#ffffff;
  --bg-overlay:rgba(29,31,40,0.55);--bg-glass:rgba(255,255,255,0.72);
  --text-primary:var(--ink-900);--text-secondary:var(--ink-600);
  --text-tertiary:var(--ink-400);--text-accent:var(--sakura-600);
  --border-light:var(--sakura-100);--border-medium:var(--sakura-200);
  --shadow-sm:0 1px 3px rgba(180,80,110,0.06),0 1px 2px rgba(180,80,110,0.04);
  --shadow-md:0 4px 14px rgba(180,80,110,0.08),0 2px 6px rgba(180,80,110,0.04);
  --shadow-lg:0 10px 30px rgba(180,80,110,0.12),0 4px 12px rgba(180,80,110,0.06);
  --shadow-xl:0 20px 50px rgba(180,80,110,0.16),0 8px 20px rgba(180,80,110,0.08);
  --radius-sm:8px;--radius-md:14px;--radius-lg:20px;--radius-xl:28px;
  --font-display:'Shippori Mincho','Noto Serif JP',serif;
  --font-body:'Zen Kaku Gothic New','Noto Serif JP',sans-serif;
  --transition-fast:0.15s cubic-bezier(0.4,0,0.2,1);
  --transition-smooth:0.3s cubic-bezier(0.4,0,0.2,1);
  --transition-spring:0.5s cubic-bezier(0.34,1.56,0.64,1);
  --sidebar-width:220px;
}

*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{font-size:15px;scroll-behavior:smooth;-webkit-font-smoothing:antialiased}
body{font-family:var(--font-body);background:var(--bg-primary);color:var(--text-primary);min-height:100vh;overflow-x:hidden}

body::before{
  content:'';position:fixed;inset:0;pointer-events:none;z-index:0;
  background:
    radial-gradient(ellipse 80% 60% at 10% 20%,rgba(248,174,186,0.12),transparent),
    radial-gradient(ellipse 60% 50% at 90% 80%,rgba(169,208,142,0.08),transparent),
    radial-gradient(ellipse 40% 40% at 50% 50%,rgba(244,122,154,0.04),transparent);
}

.app-layout{display:flex;min-height:100vh;position:relative;z-index:1}

/* Sidebar */
.sidebar{
  width:var(--sidebar-width);background:linear-gradient(180deg,#fff8f6,#fff1ed);
  border-right:1px solid var(--border-light);display:flex;flex-direction:column;
  position:fixed;top:0;left:0;bottom:0;z-index:100;transition:transform var(--transition-smooth);
}
.sidebar-header{padding:28px 20px 20px;border-bottom:1px solid var(--border-light)}
.sidebar-logo{font-family:var(--font-display);font-size:1.55rem;font-weight:800;color:var(--sakura-700);letter-spacing:0.04em}
.sidebar-logo-sub{font-family:var(--font-body);font-size:0.7rem;font-weight:300;color:var(--text-tertiary);letter-spacing:0.12em;text-transform:uppercase;margin-top:4px}
.sidebar-nav{padding:16px 12px;flex:1}

.nav-item{
  display:flex;align-items:center;gap:12px;padding:13px 16px;border-radius:var(--radius-md);
  cursor:pointer;transition:all var(--transition-fast);font-size:0.92rem;font-weight:400;
  color:var(--text-secondary);margin-bottom:4px;position:relative;overflow:hidden;
}
.nav-item::before{content:'';position:absolute;inset:0;background:linear-gradient(135deg,var(--sakura-100),var(--sakura-50));opacity:0;transition:opacity var(--transition-fast);border-radius:inherit}
.nav-item:hover{color:var(--text-primary)}.nav-item:hover::before{opacity:0.5}
.nav-item.active{color:var(--sakura-700);font-weight:700}.nav-item.active::before{opacity:1}
.nav-item.active::after{content:'';position:absolute;left:0;top:50%;transform:translateY(-50%);width:3px;height:60%;background:var(--sakura-500);border-radius:0 3px 3px 0}
.nav-icon{font-size:1.15rem;position:relative;z-index:1}
.nav-label{position:relative;z-index:1}
.nav-badge{margin-left:auto;background:var(--sakura-400);color:#fff;font-size:0.65rem;font-weight:700;padding:2px 8px;border-radius:10px;position:relative;z-index:1}
.sidebar-footer{padding:16px 20px;border-top:1px solid var(--border-light);font-size:0.7rem;color:var(--text-tertiary);text-align:center;font-weight:300;display:flex;flex-direction:column;align-items:center;gap:8px}
.settings-btn{background:none;border:none;cursor:pointer;font-size:0.75rem;color:var(--text-tertiary);padding:4px 10px;border-radius:6px;transition:all 0.2s;text-decoration:none}
.settings-btn:hover{background:var(--bg-secondary);color:var(--text-primary)}

/* Settings Modal */
.form-group{margin-bottom:16px}
.form-label{display:block;font-size:0.8rem;font-weight:500;color:var(--text-secondary);margin-bottom:6px}
.form-input{width:100%;padding:10px 12px;border:1.5px solid var(--border-light);border-radius:8px;background:var(--bg-primary);color:var(--text-primary);font-size:0.9rem;font-family:inherit;box-sizing:border-box;transition:border-color 0.2s}
.form-input:focus{outline:none;border-color:var(--matcha-400)}
.form-input code{background:rgba(0,0,0,0.06);padding:1px 4px;border-radius:3px;font-size:0.85em}
.main-content{margin-left:var(--sidebar-width);flex:1;min-height:100vh;position:relative}

/* Page Header */
.page-header{padding:32px 40px 0;position:sticky;top:0;z-index:50;background:linear-gradient(180deg,var(--bg-primary) 80%,transparent);backdrop-filter:blur(12px)}
.page-header-inner{display:flex;align-items:flex-end;justify-content:space-between;padding-bottom:24px;border-bottom:1px solid var(--border-light)}
.page-title{font-family:var(--font-display);font-size:1.7rem;font-weight:800;color:var(--ink-900);letter-spacing:0.02em}
.page-date{font-size:0.8rem;color:var(--text-tertiary);margin-top:4px;font-weight:300}
.page-actions{display:flex;gap:10px}

.btn{display:inline-flex;align-items:center;gap:6px;padding:9px 18px;border-radius:var(--radius-sm);border:none;font-family:var(--font-body);font-size:0.82rem;font-weight:500;cursor:pointer;transition:all var(--transition-fast)}
.btn-primary{background:linear-gradient(135deg,var(--sakura-500),var(--sakura-600));color:#fff;box-shadow:0 2px 8px rgba(232,77,122,0.25)}
.btn-primary:hover{transform:translateY(-1px);box-shadow:0 4px 14px rgba(232,77,122,0.35)}
.btn-ghost{background:var(--bg-glass);color:var(--text-secondary);border:1px solid var(--border-medium)}
.btn-ghost:hover{background:var(--sakura-50);color:var(--text-accent)}

/* Word Grid */
.word-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:22px;padding:32px 40px 60px}

/* Word Card */
.word-card{
  background:var(--bg-card);border-radius:var(--radius-lg);overflow:hidden;cursor:pointer;
  transition:all var(--transition-smooth);box-shadow:var(--shadow-sm);position:relative;
  animation:cardFadeIn 0.6s ease both;
}
.word-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg)}
@keyframes cardFadeIn{from{opacity:0;transform:translateY(16px)}to{opacity:1;transform:translateY(0)}}
.word-card:nth-child(1){animation-delay:.03s}.word-card:nth-child(2){animation-delay:.06s}
.word-card:nth-child(3){animation-delay:.09s}.word-card:nth-child(4){animation-delay:.12s}
.word-card:nth-child(5){animation-delay:.15s}.word-card:nth-child(6){animation-delay:.18s}
.word-card:nth-child(7){animation-delay:.21s}.word-card:nth-child(8){animation-delay:.24s}
.word-card:nth-child(9){animation-delay:.27s}.word-card:nth-child(10){animation-delay:.30s}
.word-card:nth-child(11){animation-delay:.33s}.word-card:nth-child(12){animation-delay:.36s}
.word-card:nth-child(13){animation-delay:.39s}.word-card:nth-child(14){animation-delay:.42s}
.word-card:nth-child(15){animation-delay:.45s}.word-card:nth-child(16){animation-delay:.48s}
.word-card:nth-child(17){animation-delay:.51s}.word-card:nth-child(18){animation-delay:.54s}
.word-card:nth-child(19){animation-delay:.57s}.word-card:nth-child(20){animation-delay:.60s}

.card-image-wrapper{position:relative;width:100%;aspect-ratio:4/3;overflow:hidden}
.card-image{width:100%;height:100%;object-fit:cover;transition:transform 0.6s cubic-bezier(0.25,0.46,0.45,0.94)}
.word-card:hover .card-image{transform:scale(1.06)}
.card-image-overlay{position:absolute;inset:0;background:linear-gradient(0deg,rgba(29,31,40,0.65) 0%,rgba(29,31,40,0.15) 45%,transparent 70%)}

.card-word-overlay{position:absolute;bottom:14px;left:16px;right:16px;z-index:2}
.card-kanji{font-family:var(--font-display);font-size:2.1rem;font-weight:800;color:#fff;text-shadow:0 2px 12px rgba(0,0,0,0.3);line-height:1.15}
.card-reading{font-size:0.78rem;color:rgba(255,255,255,0.85);font-weight:300;margin-top:2px}

.card-fav-btn{
  position:absolute;top:12px;right:12px;z-index:5;width:36px;height:36px;border-radius:50%;
  background:rgba(255,255,255,0.85);backdrop-filter:blur(8px);border:none;cursor:pointer;
  display:flex;align-items:center;justify-content:center;font-size:1rem;
  transition:all var(--transition-fast);color:var(--ink-300);
}
.card-fav-btn:hover{background:#fff;transform:scale(1.1)}
.card-fav-btn.favorited{color:var(--sakura-500);background:#fff}
.card-fav-btn.favorited::after{content:'';position:absolute;inset:-4px;border-radius:50%;background:rgba(232,77,122,0.15);animation:favPulse 0.6s ease-out}
@keyframes favPulse{0%{transform:scale(0.8);opacity:1}100%{transform:scale(1.4);opacity:0}}

.card-heat-badge{
  position:absolute;top:12px;left:12px;z-index:3;display:flex;align-items:center;gap:4px;
  padding:4px 10px;border-radius:12px;background:rgba(255,255,255,0.88);backdrop-filter:blur(6px);
  font-size:0.68rem;font-weight:700;color:var(--sakura-600);
}
.heat-fire{font-size:0.8rem}

.card-body{padding:16px 18px 18px}
.card-meaning{font-size:0.88rem;color:var(--text-primary);line-height:1.55;font-weight:400;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.card-meta{display:flex;align-items:center;justify-content:space-between;margin-top:12px;padding-top:10px;border-top:1px solid var(--sakura-50)}
.card-source{font-size:0.68rem;color:var(--text-tertiary);font-weight:300;display:flex;align-items:center;gap:4px}
.card-source-icon{width:14px;height:14px;border-radius:3px;background:var(--matcha-200);display:inline-flex;align-items:center;justify-content:center;font-size:0.5rem;font-weight:700;color:var(--matcha-700)}
.card-heat-bar{display:flex;align-items:center;gap:5px}
.heat-bar-track{width:60px;height:4px;background:var(--sakura-50);border-radius:2px;overflow:hidden}
.heat-bar-fill{height:100%;border-radius:2px;background:linear-gradient(90deg,var(--sakura-300),var(--sakura-500));transition:width 1s ease-out}
.heat-value{font-size:0.65rem;font-weight:700;color:var(--sakura-500);min-width:28px;text-align:right}

/* Empty State */
.empty-state{display:flex;flex-direction:column;align-items:center;justify-content:center;padding:80px 40px;text-align:center}
.empty-icon{font-size:4rem;margin-bottom:16px;opacity:0.6}
.empty-title{font-family:var(--font-display);font-size:1.2rem;font-weight:600;color:var(--text-secondary);margin-bottom:8px}
.empty-desc{font-size:0.85rem;color:var(--text-tertiary);max-width:300px;line-height:1.6}

/* ═══ Detail Modal ═══ */
.modal-overlay{
  position:fixed;inset:0;background:var(--bg-overlay);z-index:1000;display:flex;align-items:center;justify-content:center;
  opacity:0;visibility:hidden;transition:all var(--transition-smooth);backdrop-filter:blur(6px);
}
.modal-overlay.open{opacity:1;visibility:visible}
.modal-container{
  background:var(--bg-card);border-radius:var(--radius-xl);width:92vw;max-width:780px;max-height:88vh;
  overflow-y:auto;box-shadow:var(--shadow-xl);transform:translateY(20px) scale(0.97);
  transition:transform var(--transition-spring);
}
.modal-overlay.open .modal-container{transform:translateY(0) scale(1)}

.modal-hero{position:relative;width:100%;aspect-ratio:16/8;overflow:hidden;border-radius:var(--radius-xl) var(--radius-xl) 0 0}
.modal-hero-img{width:100%;height:100%;object-fit:cover}
.modal-hero-overlay{position:absolute;inset:0;background:linear-gradient(0deg,rgba(29,31,40,0.7) 0%,rgba(29,31,40,0.2) 50%,transparent 80%)}
.modal-hero-content{position:absolute;bottom:24px;left:32px;right:32px;z-index:2}
.modal-kanji{font-family:var(--font-display);font-size:3rem;font-weight:800;color:#fff;text-shadow:0 2px 16px rgba(0,0,0,0.3);line-height:1.1}
.modal-reading-hero{font-size:0.95rem;color:rgba(255,255,255,0.8);font-weight:300;margin-top:4px}

.modal-close{
  position:absolute;top:16px;right:16px;z-index:10;width:40px;height:40px;border-radius:50%;
  background:rgba(255,255,255,0.85);backdrop-filter:blur(8px);border:none;cursor:pointer;font-size:1.2rem;
  color:var(--ink-600);display:flex;align-items:center;justify-content:center;transition:all var(--transition-fast);
}
.modal-close:hover{background:#fff;transform:rotate(90deg)}

.modal-fav-btn{
  position:absolute;top:16px;right:68px;z-index:10;width:40px;height:40px;border-radius:50%;
  background:rgba(255,255,255,0.85);backdrop-filter:blur(8px);border:none;cursor:pointer;font-size:1.15rem;
  color:var(--ink-300);display:flex;align-items:center;justify-content:center;transition:all var(--transition-fast);
}
.modal-fav-btn:hover{background:#fff;transform:scale(1.1)}
.modal-fav-btn.favorited{color:var(--sakura-500)}

.modal-body{padding:28px 32px 36px}
.modal-meaning-main{font-size:1.05rem;color:var(--text-primary);line-height:1.7;margin-bottom:24px;padding-bottom:20px;border-bottom:1px dashed var(--border-medium)}
.modal-section{margin-bottom:24px}
.modal-section-title{font-family:var(--font-display);font-size:0.85rem;font-weight:600;color:var(--sakura-700);margin-bottom:10px;display:flex;align-items:center;gap:8px}
.modal-section-title::before{content:'';display:inline-block;width:3px;height:14px;background:linear-gradient(180deg,var(--sakura-400),var(--sakura-600));border-radius:2px}
.modal-section-content{font-size:0.9rem;color:var(--text-secondary);line-height:1.75}

.synonym-tags{display:flex;flex-wrap:wrap;gap:8px}
.synonym-tag{padding:5px 14px;border-radius:20px;background:var(--sakura-50);color:var(--sakura-700);font-size:0.8rem;font-weight:500;border:1px solid var(--sakura-100);transition:all var(--transition-fast)}
.synonym-tag:hover{background:var(--sakura-100);border-color:var(--sakura-200)}

.wrong-usage-box{background:linear-gradient(135deg,#fff5f5,#fff0f0);border:1px solid #fde2e2;border-radius:var(--radius-md);padding:14px 18px;font-size:0.85rem;color:#c0392b;line-height:1.65}
.wrong-usage-box .correct{color:var(--matcha-600);font-weight:500}

.example-item{padding:12px 16px;background:var(--ink-50);border-radius:var(--radius-sm);margin-bottom:8px;font-size:0.88rem;line-height:1.7}
.example-jp{font-weight:500;color:var(--text-primary)}
.example-cn{color:var(--text-tertiary);font-size:0.82rem;margin-top:3px}

.interaction-box{background:linear-gradient(135deg,var(--sakura-50),var(--matcha-50));border:1px solid var(--sakura-100);border-radius:var(--radius-md);padding:18px 20px;position:relative;overflow:hidden}
.interaction-box::before{content:'💬';position:absolute;top:-8px;right:12px;font-size:3rem;opacity:0.15}
.interaction-question{font-family:var(--font-display);font-size:0.95rem;font-weight:600;color:var(--sakura-800);line-height:1.5}
.interaction-hint{font-size:0.75rem;color:var(--text-tertiary);margin-top:6px}

.modal-meta-bar{display:flex;align-items:center;gap:16px;padding:14px 0 0;margin-top:8px;border-top:1px solid var(--border-light);font-size:0.75rem;color:var(--text-tertiary)}
.modal-meta-item{display:flex;align-items:center;gap:5px}

/* Scrollbar */
::-webkit-scrollbar{width:6px}
::-webkit-scrollbar-track{background:transparent}
::-webkit-scrollbar-thumb{background:var(--sakura-200);border-radius:3px}
::-webkit-scrollbar-thumb:hover{background:var(--sakura-300)}
.modal-container::-webkit-scrollbar{width:5px}

/* Page */
.page{display:none}
.page.active{display:block;animation:pageIn 0.4s ease both}
@keyframes pageIn{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}

/* Toast */
.toast{position:fixed;bottom:32px;left:50%;transform:translateX(-50%) translateY(80px);background:var(--ink-800);color:#fff;padding:12px 24px;border-radius:var(--radius-md);font-size:0.85rem;font-weight:400;box-shadow:var(--shadow-lg);z-index:9999;opacity:0;transition:all var(--transition-smooth);pointer-events:none}
.toast.show{opacity:1;transform:translateX(-50%) translateY(0)}

/* Mobile */
.mobile-toggle{display:none;position:fixed;top:16px;left:16px;z-index:200;width:44px;height:44px;border-radius:var(--radius-sm);background:var(--bg-card);border:1px solid var(--border-light);box-shadow:var(--shadow-md);cursor:pointer;font-size:1.2rem;align-items:center;justify-content:center}
@media(max-width:900px){
  .sidebar{transform:translateX(-100%)}
  .sidebar.open{transform:translateX(0);box-shadow:var(--shadow-xl)}
  .main-content{margin-left:0}
  .mobile-toggle{display:flex}
  .word-grid{padding:24px 20px 40px;gap:16px}
  .page-header{padding:72px 20px 0}
}
@media(max-width:600px){
  .word-grid{grid-template-columns:repeat(auto-fill,minmax(160px,1fr));gap:12px;padding:16px 12px 32px}
  .card-kanji{font-size:1.5rem}
  .page-header{padding:68px 16px 0}
  .page-header-inner{flex-direction:column;align-items:flex-start;gap:12px}
  .modal-container{width:96vw;max-height:92vh}
  .modal-body{padding:20px 18px 28px}
  .modal-kanji{font-size:2.2rem}
}