/* ============ 主题变量 ============ */
:root {
  --bg: #f4f6fb;
  --bg2: #e8ecf6;
  --text: #1c2333;
  --muted: #6b7390;
  --card: rgba(255, 255, 255, 0.62);
  --card-strong: rgba(255, 255, 255, 0.85);
  --border: rgba(30, 45, 90, 0.10);
  --accent: #5b6cff;
  --accent2: #8a5bff;
  --accent-soft: rgba(91, 108, 255, 0.10);
  --shadow: 0 8px 30px rgba(40, 55, 120, 0.08);
  --good: #0f9d6e;
  --bad: #e5484d;
  --warn: #e09b12;
}

html[data-theme="dark"] {
  --bg: #0d1120;
  --bg2: #121829;
  --text: #eef1fa;
  --muted: #94a0c3;
  --card: rgba(28, 36, 66, 0.55);
  --card-strong: rgba(28, 36, 66, 0.88);
  --border: rgba(160, 180, 255, 0.12);
  --accent: #7c8bff;
  --accent2: #a06bff;
  --accent-soft: rgba(124, 139, 255, 0.14);
  --shadow: 0 8px 30px rgba(0, 0, 0, 0.35);
  --good: #35c48f;
  --bad: #ff6b70;
  --warn: #f2b544;
}

/* ============ 基础 ============ */
* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  background: linear-gradient(160deg, var(--bg), var(--bg2));
  color: var(--text);
  min-height: 100vh;
  transition: background 0.3s, color 0.3s;
  -webkit-font-smoothing: antialiased;
}

.bg-glow {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background:
    radial-gradient(600px 300px at 15% -5%, var(--accent-soft), transparent 60%),
    radial-gradient(500px 260px at 90% 10%, rgba(160, 80, 255, 0.12), transparent 60%);
}

.hidden { display: none !important; }

/* ============ 顶栏 ============ */
.topbar {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(16px) saturate(1.4);
  -webkit-backdrop-filter: blur(16px) saturate(1.4);
  background: var(--card);
  border-bottom: 1px solid var(--border);
}

.topbar-inner {
  max-width: 1080px;
  margin: 0 auto;
  padding: 12px 20px;
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}

.brand { display: flex; align-items: center; gap: 8px; font-weight: 700; font-size: 18px; }
.brand-icon {
  display: inline-flex; align-items: center; justify-content: center;
  width: 30px; height: 30px; border-radius: 9px;
  background: linear-gradient(135deg, var(--accent), var(--accent2));
  color: #fff; font-size: 16px;
}

.tabs { display: flex; gap: 6px; flex: 1; flex-wrap: wrap; }

.tab {
  appearance: none; border: 1px solid var(--border); background: transparent;
  color: var(--muted); padding: 8px 14px; border-radius: 999px;
  font-size: 14px; cursor: pointer; transition: all 0.2s;
}
.tab:hover { color: var(--text); border-color: var(--accent); }
.tab.active {
  color: #fff;
  background: linear-gradient(135deg, var(--accent), var(--accent2));
  border-color: transparent;
  box-shadow: 0 4px 14px rgba(91, 108, 255, 0.35);
}

.theme-toggle {
  appearance: none; border: 1px solid var(--border); background: transparent;
  color: var(--text); width: 38px; height: 38px; border-radius: 50%;
  font-size: 17px; cursor: pointer; transition: all 0.2s;
}
.theme-toggle:hover { border-color: var(--accent); }

.lang-select {
  appearance: none; border: 1px solid var(--border); background: var(--card-strong);
  color: var(--text); border-radius: 999px; padding: 7px 30px 7px 14px;
  font-size: 13px; cursor: pointer; outline: none; transition: border 0.2s;
  background-image: linear-gradient(45deg, transparent 50%, var(--muted) 50%),
    linear-gradient(135deg, var(--muted) 50%, transparent 50%);
  background-position: calc(100% - 16px) 55%, calc(100% - 11px) 55%;
  background-size: 5px 5px;
  background-repeat: no-repeat;
}
.lang-select:hover { border-color: var(--accent); }
.lang-select option { background: var(--card-strong); color: var(--text); }

/* ============ 主区 ============ */
.container { max-width: 1080px; margin: 0 auto; padding: 28px 20px 60px; }

.panel { display: none; animation: fadeIn 0.25s ease; }
.panel.active { display: block; }

@keyframes fadeIn { from { opacity: 0; transform: translateY(6px); } to { opacity: 1; transform: none; } }

.hero { margin-bottom: 22px; }
.hero h1 { font-size: 28px; letter-spacing: 0.5px; }
.hero p { color: var(--muted); margin-top: 6px; }

/* ============ 卡片 ============ */
.card {
  background: var(--card);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 20px;
  box-shadow: var(--shadow);
}

/* ============ 单位换算 ============ */
.cat-chips { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 18px; }

.chip {
  appearance: none; border: 1px solid var(--border); background: var(--card-strong);
  color: var(--text); padding: 7px 14px; border-radius: 999px; font-size: 13.5px;
  cursor: pointer; transition: all 0.2s;
}
.chip:hover { transform: translateY(-1px); }
.chip.active {
  color: #fff;
  background: linear-gradient(135deg, var(--accent), var(--accent2));
  border-color: transparent;
}

.conv-grid { display: grid; grid-template-columns: 340px 1fr; gap: 18px; }
@media (max-width: 780px) { .conv-grid { grid-template-columns: 1fr; } }

.input-card {}
.input-row { display: flex; gap: 10px; margin-bottom: 12px; }
.input-row input {
  flex: 1; min-width: 0;
  background: var(--card-strong); border: 1px solid var(--border); color: var(--text);
  border-radius: 14px; padding: 12px 14px; font-size: 20px; outline: none; transition: border 0.2s;
}
.input-row input:focus { border-color: var(--accent); }
.input-row select {
  background: var(--card-strong); border: 1px solid var(--border); color: var(--text);
  border-radius: 14px; padding: 10px; font-size: 15px; outline: none; max-width: 150px;
}

.ghost-btn {
  appearance: none; border: 1px solid var(--border); background: transparent; color: var(--muted);
  padding: 7px 14px; border-radius: 10px; font-size: 13px; cursor: pointer; transition: all 0.2s;
}
.ghost-btn:hover { color: var(--text); border-color: var(--accent); }

.hint { color: var(--muted); font-size: 12.5px; margin-top: 10px; }

.results-card { max-height: 520px; overflow: auto; }
.results-list { display: flex; flex-direction: column; gap: 8px; }

.result-row {
  display: flex; align-items: center; justify-content: space-between; gap: 10px;
  background: var(--card-strong); border: 1px solid var(--border);
  border-radius: 12px; padding: 10px 14px; cursor: pointer; transition: all 0.15s;
}
.result-row:hover { border-color: var(--accent); transform: translateX(2px); }
.result-row .u-name { color: var(--muted); font-size: 13px; }
.result-row .u-val { font-family: ui-monospace, "SF Mono", Consolas, monospace; font-size: 15px; font-weight: 600; word-break: break-all; text-align: right; }
.result-row.selected { border-color: var(--accent); background: var(--accent-soft); }

/* ============ 货币 ============ */
.currency-card { max-width: 560px; margin: 0 auto; }
.cur-row { display: flex; gap: 10px; align-items: center; }
.cur-row input {
  flex: 1; min-width: 0;
  background: var(--card-strong); border: 1px solid var(--border); color: var(--text);
  border-radius: 14px; padding: 14px; font-size: 22px; outline: none;
}
.cur-row input:focus { border-color: var(--accent); }
.cur-row select { background: var(--card-strong); border: 1px solid var(--border); color: var(--text); border-radius: 14px; padding: 12px; font-size: 15px; max-width: 130px; }
.cur-swap-row { display: flex; justify-content: center; margin: 10px 0; }

.icon-btn {
  appearance: none; width: 42px; height: 42px; border-radius: 50%;
  border: 1px solid var(--border); background: var(--card-strong); color: var(--text);
  font-size: 18px; cursor: pointer; transition: all 0.2s;
}
.icon-btn:hover { border-color: var(--accent); transform: rotate(180deg); }

.cur-output { display: block; flex: 1; font-size: 26px; font-weight: 700; font-family: ui-monospace, Consolas, monospace; padding: 10px 0; }
.cur-meta { display: flex; align-items: center; justify-content: space-between; margin-top: 12px; gap: 10px; }

.notice {
  margin-top: 14px; padding: 12px 14px; border-radius: 12px; font-size: 13.5px;
  background: rgba(224, 155, 18, 0.12); border: 1px solid rgba(224, 155, 18, 0.4); color: var(--warn);
}

/* ============ 进制 ============ */
.base-card { max-width: 640px; margin: 0 auto; }

.base-outputs { display: grid; gap: 10px; margin-top: 16px; }
.base-row {
  display: flex; align-items: center; justify-content: space-between; gap: 10px;
  background: var(--card-strong); border: 1px solid var(--border); border-radius: 12px; padding: 12px 14px;
}
.base-row .b-name { color: var(--muted); font-size: 13px; min-width: 72px; }
.base-row .b-val { font-family: ui-monospace, Consolas, monospace; font-size: 16px; font-weight: 600; word-break: break-all; text-align: right; flex: 1; }

.copy-btn {
  appearance: none; border: 1px solid var(--border); background: transparent; color: var(--muted);
  border-radius: 8px; padding: 5px 10px; font-size: 12px; cursor: pointer; transition: all 0.2s;
}
.copy-btn:hover { color: var(--text); border-color: var(--accent); }

/* ============ 计算器 ============ */
.calc-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 18px; }

.calc-card h3 { font-size: 16px; margin-bottom: 14px; }
.calc-card label { display: block; font-size: 13px; color: var(--muted); margin-bottom: 10px; }
.calc-card label input, .calc-card label select {
  display: block; width: 100%; margin-top: 5px;
  background: var(--card-strong); border: 1px solid var(--border); color: var(--text);
  border-radius: 12px; padding: 11px 12px; font-size: 15px; outline: none;
}
.calc-card label input:focus { border-color: var(--accent); }

.calc-btn {
  appearance: none; width: 100%; border: none; cursor: pointer;
  background: linear-gradient(135deg, var(--accent), var(--accent2)); color: #fff;
  border-radius: 12px; padding: 12px; font-size: 15px; font-weight: 600; transition: all 0.2s;
}
.calc-btn:hover { filter: brightness(1.08); transform: translateY(-1px); }

.result { margin-top: 12px; font-size: 14.5px; line-height: 1.6; min-height: 20px; color: var(--text); }
.result b { color: var(--accent); font-size: 18px; }
.result .tag { display: inline-block; margin-left: 6px; padding: 2px 10px; border-radius: 999px; font-size: 12px; color: #fff; }

/* ============ 页脚 / Toast ============ */
.footer { text-align: center; color: var(--muted); font-size: 12.5px; padding: 24px 16px 36px; }

.toast {
  position: fixed; left: 50%; bottom: 32px; transform: translateX(-50%);
  background: var(--card-strong); border: 1px solid var(--border); color: var(--text);
  padding: 10px 18px; border-radius: 12px; font-size: 13.5px; box-shadow: var(--shadow);
  backdrop-filter: blur(10px); z-index: 100;
}

/* ============ RTL（阿拉伯语） ============ */
html[dir="rtl"] body { text-align: right; }
html[dir="rtl"] .topbar-inner,
html[dir="rtl"] .brand,
html[dir="rtl"] .tabs,
html[dir="rtl"] .cat-chips,
html[dir="rtl"] .input-row,
html[dir="rtl"] .cur-row,
html[dir="rtl"] .cur-meta,
html[dir="rtl"] .result-row,
html[dir="rtl"] .base-row { direction: rtl; }
html[dir="rtl"] .lang-select {
  padding: 7px 14px 7px 30px;
  background-position: 16px 55%, 11px 55%;
}
html[dir="rtl"] .result-row:hover { transform: translateX(-2px); }
html[dir="rtl"] .result-row .u-val,
html[dir="rtl"] .base-row .b-val,
html[dir="rtl"] .cur-output,
html[dir="rtl"] input[type="number"],
html[dir="rtl"] #base-input { direction: ltr; text-align: right; }
html[dir="rtl"] .result .tag { margin-left: 0; margin-right: 6px; }
html[dir="rtl"] .toast { direction: rtl; }