:root {
    --bg-color: #0f172a;
    --bg-gradient-1: rgba(99, 102, 241, 0.15);
    --bg-gradient-2: rgba(20, 184, 166, 0.15);
    --card-bg: rgba(30, 41, 59, 0.7);
    --card-border: rgba(255, 255, 255, 0.08);
    --card-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
    --text-main: #f1f5f9;
    --text-muted: #94a3b8;
    --text-dim: rgba(255, 255, 255, 0.3);
    --input-bg: rgba(0, 0, 0, 0.2);
    --input-border: rgba(255, 255, 255, 0.1);
    --pill-bg: rgba(255, 255, 255, 0.05);
    --pill-hover: rgba(255, 255, 255, 0.1);
    --item-hover: rgba(255, 255, 255, 0.06);
    --theme-file: #6366f1;
    --theme-file-dim: rgba(99, 102, 241, 0.15);
    --theme-bw: #14b8a6;
    --theme-bw-dim: rgba(20, 184, 166, 0.15);
    --theme-refund: #f59e0b;
    --theme-refund-dim: rgba(245, 158, 11, 0.15);
    --theme-sign: #7c3aed;
    --theme-sign-dim: rgba(124, 58, 237, 0.15);
    --nav-bg: rgba(0, 0, 0, 0.3);
}

body.light-mode {
    --bg-color: #f0f4f8;
    --bg-gradient-1: rgba(99, 102, 241, 0.08);
    --bg-gradient-2: rgba(20, 184, 166, 0.08);
    --card-bg: #ffffff;
    --card-border: rgba(0, 0, 0, 0.04);
    --card-shadow: 0 4px 20px rgba(0, 0, 0, 0.05);
    --text-main: #1e293b;
    --text-muted: #64748b;
    --text-dim: rgba(0, 0, 0, 0.3);
    --input-bg: #f8fafc;
    --input-border: #e2e8f0;
    --pill-bg: #f1f5f9;
    --pill-hover: #e2e8f0;
    --item-hover: #f8fafc;
    --theme-file: #4f46e5;
    --theme-file-dim: rgba(79, 70, 229, 0.1);
    --theme-bw: #0d9488;
    --theme-bw-dim: rgba(13, 148, 136, 0.1);
    --theme-refund: #d97706;
    --theme-refund-dim: rgba(217, 119, 6, 0.1);
    --theme-sign: #7c3aed;
    --theme-sign-dim: rgba(124, 58, 237, 0.1);
    --nav-bg: rgba(255, 255, 255, 0.6);
}

* { margin: 0; padding: 0; box-sizing: border-box; -webkit-tap-highlight-color: transparent; }

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background-color: var(--bg-color);
    background-image:
        radial-gradient(circle at 10% 20%, var(--bg-gradient-1) 0%, transparent 40%),
        radial-gradient(circle at 90% 80%, var(--bg-gradient-2) 0%, transparent 40%);
    color: var(--text-main);
    min-height: 100vh;
    padding-bottom: 40px;
    transition: background-color 0.3s ease, color 0.3s ease;
}

.container { max-width: 800px; margin: 0 auto; padding: 20px; }

.top-bar { display: flex; justify-content: center; align-items: center; margin-bottom: 30px; position: relative; }

.nav-wrapper { display: flex; gap: 8px; padding: 5px; background: var(--nav-bg); border-radius: 16px; backdrop-filter: blur(10px); border: 1px solid var(--card-border); }

.nav-btn { padding: 10px 24px; border-radius: 12px; border: none; background: transparent; color: var(--text-muted); font-weight: 600; cursor: pointer; transition: all 0.3s ease; font-size: 0.95rem; }
.nav-btn.active { color: #fff; box-shadow: 0 4px 12px rgba(0,0,0,0.1); }
.nav-btn[data-target="file"].active { background: var(--theme-file); }
.nav-btn[data-target="bw"].active { background: var(--theme-bw); }
.nav-btn[data-target="refund"].active { background: var(--theme-refund); }
.nav-btn[data-target="sign"].active { background: var(--theme-sign); }

.theme-toggle { position: absolute; right: 0; top: 50%; transform: translateY(-50%); width: 40px; height: 40px; border-radius: 50%; background: var(--card-bg); border: 1px solid var(--card-border); color: var(--text-main); display: flex; align-items: center; justify-content: center; cursor: pointer; font-size: 1.2rem; transition: all 0.3s; box-shadow: var(--card-shadow); }
.theme-toggle:hover { transform: translateY(-50%) scale(1.1); }

.panel { display: none; animation: fadeIn 0.4s ease; }
.panel.active { display: block; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: translateY(0); } }

.card {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 20px;
    padding: 24px;
    margin-bottom: 20px;
    backdrop-filter: blur(12px);
    box-shadow: var(--card-shadow);
    transition: background 0.3s, border-color 0.3s, box-shadow 0.3s;
    overflow: hidden;
}

.input-group { display: flex; flex-direction: column; align-items: center; gap: 16px; }

.main-input-wrapper { position: relative; width: 100%; max-width: 400px; }

.main-input { width: 100%; background: var(--input-bg); border: 2px solid var(--input-border); border-radius: 16px; padding: 20px; font-size: 2.5rem; font-weight: 700; color: var(--text-main); text-align: center; outline: none; transition: border-color 0.3s, background 0.3s, color 0.3s; -moz-appearance: textfield; }
.main-input::-webkit-outer-spin-button, .main-input::-webkit-inner-spin-button { -webkit-appearance: none; margin: 0; }
.main-input:focus { border-color: var(--active-color); background: var(--card-bg); }

.unit-badge { position: absolute; right: 20px; top: 50%; transform: translateY(-50%); font-size: 1rem; font-weight: 600; color: var(--active-color); opacity: 0.9; }

.quick-pills { display: flex; flex-wrap: wrap; justify-content: center; gap: 8px; }
.pill { padding: 6px 14px; border-radius: 20px; background: var(--pill-bg); border: 1px solid transparent; color: var(--text-muted); font-size: 0.85rem; cursor: pointer; transition: all 0.2s; }
.pill:hover { background: var(--pill-hover); color: var(--text-main); }

.unit-selector { display: flex; gap: 8px; overflow-x: auto; padding-bottom: 8px; width: 100%; justify-content: flex-start; scrollbar-width: none; }
.unit-selector::-webkit-scrollbar { display: none; }
@media(min-width: 600px) { .unit-selector { justify-content: center; } }

.unit-btn { flex: 0 0 auto; padding: 10px 20px; border-radius: 12px; background: var(--pill-bg); border: 1px solid var(--card-border); color: var(--text-muted); cursor: pointer; transition: all 0.2s; min-width: 70px; text-align: center; }
.unit-btn.active { background: var(--active-color); border-color: var(--active-color); color: #fff; font-weight: 600; box-shadow: 0 4px 10px rgba(0,0,0,0.15); }

.base-toggle { display: flex; background: var(--input-bg); padding: 4px; border-radius: 10px; margin-top: 10px; }
.base-opt { padding: 6px 16px; border-radius: 8px; font-size: 0.8rem; color: var(--text-muted); cursor: pointer; transition: all 0.2s; }
.base-opt.active { background: var(--theme-file); color: #fff; }

.result-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(160px, 1fr)); gap: 12px; margin-top: 20px; }

.res-item { background: var(--pill-bg); border: 1px solid var(--card-border); border-radius: 12px; padding: 16px; cursor: pointer; transition: transform 0.2s, background 0.2s; position: relative; overflow: hidden; }
.res-item:hover { background: var(--item-hover); transform: translateY(-2px); }
.res-item.highlight { background: var(--active-bg-dim); border-color: var(--active-color); }
.res-label { font-size: 0.75rem; color: var(--text-muted); text-transform: uppercase; letter-spacing: 1px; margin-bottom: 4px; }
.res-val { font-size: 1.4rem; font-weight: 700; color: var(--text-main); word-break: break-all; }
.res-sub { font-size: 0.7rem; color: var(--text-dim); margin-top: 4px; }
.res-item.highlight .res-val { color: var(--active-color); }
.res-item.highlight .res-sub { color: var(--active-color); opacity: 0.7; }

.bw-visualizer { display: flex; align-items: center; justify-content: space-between; background: var(--input-bg); border-radius: 16px; padding: 24px; margin-bottom: 20px; position: relative; overflow: hidden; border: 1px solid var(--card-border); }
.bw-v-item { text-align: center; z-index: 2; flex: 1; }
.bw-v-val { font-size: 2rem; font-weight: 800; line-height: 1.2; }
.bw-v-unit { font-size: 0.9rem; color: var(--text-muted); }
.bw-divider { font-size: 1.5rem; color: var(--text-dim); padding: 0 10px; }
.color-net { color: #a78bfa; }
.color-disk { color: #34d399; }
body.light-mode .color-net { color: #7c3aed; }
body.light-mode .color-disk { color: #059669; }

.dl-title { font-size: 0.9rem; color: var(--text-muted); margin-bottom: 12px; display: flex; align-items: center; gap: 8px; }
.dl-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 10px; }
.dl-row { display: flex; justify-content: space-between; align-items: center; background: var(--pill-bg); padding: 10px 14px; border-radius: 8px; }
.dl-name { font-size: 0.85rem; color: var(--text-muted); }
.dl-val { font-size: 0.9rem; font-weight: 600; color: var(--text-main); }

.est-card-title { font-size: 1rem; font-weight: 700; color: var(--text-main); margin-bottom: 16px; display: flex; align-items: center; gap: 10px; }

.est-row {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    gap: 10px;
    align-items: start;
    margin-bottom: 20px;
    width: 100%;
}

.est-block {
    background: var(--input-bg);
    border: 1px solid var(--card-border);
    border-radius: 14px;
    padding: 14px;
    display: flex;
    flex-direction: column;
    gap: 8px;
    min-width: 0;
    overflow: hidden;
}

.est-block-label { font-size: 0.75rem; font-weight: 600; color: var(--text-muted); letter-spacing: 0.5px; }

.est-input {
    width: 100%;
    background: var(--card-bg);
    border: 2px solid var(--input-border);
    border-radius: 10px;
    padding: 10px 8px;
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--text-main);
    text-align: center;
    outline: none;
    transition: border-color 0.3s, background 0.3s;
    -moz-appearance: textfield;
    min-width: 0;
}
.est-input::-webkit-outer-spin-button, .est-input::-webkit-inner-spin-button { -webkit-appearance: none; margin: 0; }
.est-input:focus { border-color: var(--theme-bw); }

.est-unit-pills { display: flex; gap: 4px; flex-wrap: wrap; }

.est-unit-pill { padding: 4px 10px; border-radius: 8px; background: var(--pill-bg); border: 1px solid var(--card-border); color: var(--text-muted); font-size: 0.75rem; font-weight: 600; cursor: pointer; transition: all 0.2s; white-space: nowrap; }
.est-unit-pill:hover { background: var(--pill-hover); color: var(--text-main); }
.est-unit-pill.active { background: var(--theme-bw); color: #fff; border-color: var(--theme-bw); }

.est-quick-row { display: flex; gap: 4px; flex-wrap: wrap; }
.est-quick-pill { padding: 3px 7px; border-radius: 6px; background: var(--pill-bg); color: var(--text-dim); font-size: 0.65rem; cursor: pointer; transition: all 0.2s; white-space: nowrap; }
.est-quick-pill:hover { background: var(--pill-hover); color: var(--text-main); }

.est-swap-btn {
    width: 32px; height: 32px; min-width: 32px;
    border-radius: 50%;
    background: var(--theme-bw); border: none; color: #fff;
    font-size: 0.9rem; cursor: pointer;
    transition: all 0.3s;
    display: flex; align-items: center; justify-content: center;
    margin-top: 42px;
}
.est-swap-btn:hover { transform: scale(1.15) rotate(180deg); }

.est-result-box {
    background: linear-gradient(135deg, var(--theme-bw-dim), rgba(20, 184, 166, 0.03));
    border: 1px solid var(--theme-bw);
    border-radius: 14px;
    padding: 20px 16px;
    text-align: center;
    position: relative;
    overflow: hidden;
}
.est-result-box::before { content: ''; position: absolute; top: -50%; left: -50%; width: 200%; height: 200%; background: radial-gradient(circle, rgba(20,184,166,0.06) 0%, transparent 60%); pointer-events: none; }

.est-result-time { font-size: 2rem; font-weight: 800; color: var(--theme-bw); line-height: 1.2; margin-bottom: 6px; position: relative; }

.est-result-detail { font-size: 0.78rem; color: var(--text-muted); line-height: 1.6; position: relative; word-break: break-word; }
.est-result-detail span { color: var(--text-main); font-weight: 600; }

.est-progress-bar { margin-top: 14px; height: 5px; background: var(--input-bg); border-radius: 3px; overflow: hidden; position: relative; }
.est-progress-fill { height: 100%; background: linear-gradient(90deg, var(--theme-bw), #a78bfa); border-radius: 3px; transition: width 0.6s ease; }

.est-scenarios { display: grid; grid-template-columns: repeat(3, 1fr); gap: 6px; margin-top: 14px; }

.est-scenario { background: var(--pill-bg); border: 1px solid var(--card-border); border-radius: 10px; padding: 10px 6px; text-align: center; cursor: pointer; transition: all 0.2s; }
.est-scenario:hover { background: var(--item-hover); transform: translateY(-1px); }
.est-scenario-pct { font-size: 0.65rem; color: var(--text-dim); margin-bottom: 2px; }
.est-scenario-label { font-size: 0.7rem; color: var(--text-muted); margin-bottom: 3px; }
.est-scenario-val { font-size: 0.95rem; font-weight: 700; color: var(--text-main); }

.refund-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    margin-bottom: 16px;
}

.refund-block {
    background: var(--input-bg);
    border: 1px solid var(--card-border);
    border-radius: 16px;
    padding: 16px;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.refund-label {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-muted);
    display: flex;
    align-items: center;
    gap: 6px;
}

.refund-input-wrapper {
    position: relative;
}

.refund-input {
    width: 100%;
    background: var(--card-bg);
    border: 2px solid var(--input-border);
    border-radius: 12px;
    padding: 14px 12px;
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--text-main);
    outline: none;
    transition: border-color 0.3s, background 0.3s;
}

.refund-input:focus {
    border-color: var(--theme-refund);
}

.refund-copy-btn {
    position: absolute;
    right: 8px;
    top: 50%;
    transform: translateY(-50%);
    background: var(--pill-bg);
    border: 1px solid var(--card-border);
    border-radius: 8px;
    padding: 6px 10px;
    font-size: 0.75rem;
    cursor: pointer;
    color: var(--text-muted);
    transition: all 0.2s;
}

.refund-copy-btn:hover {
    background: var(--pill-hover);
    color: var(--text-main);
}

.refund-quick-buttons {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

.refund-quick-btn {
    padding: 8px 16px;
    border-radius: 10px;
    background: var(--pill-bg);
    border: 1px solid var(--card-border);
    color: var(--text-muted);
    font-size: 0.85rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
}

.refund-quick-btn:hover {
    background: var(--pill-hover);
    color: var(--text-main);
    border-color: var(--theme-refund);
}

.refund-type-btn {
    padding: 10px 24px;
    border-radius: 12px;
    background: var(--pill-bg);
    border: 1px solid var(--card-border);
    color: var(--text-muted);
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
}

.refund-type-btn.active {
    background: var(--theme-refund);
    color: #fff;
    border-color: var(--theme-refund);
}

.refund-type-btn:hover:not(.active) {
    background: var(--pill-hover);
    color: var(--text-main);
}

.refund-result-box {
    background: linear-gradient(135deg, var(--theme-refund-dim), rgba(245, 158, 11, 0.03));
    border: 1px solid var(--theme-refund);
    border-radius: 16px;
    padding: 20px;
    position: relative;
    overflow: hidden;
}

.refund-result-box::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(245, 158, 11, 0.06) 0%, transparent 60%);
    pointer-events: none;
}

.refund-copy-all-btn {
    background: var(--theme-refund);
    border: none;
    color: #fff;
    padding: 8px 16px;
    border-radius: 10px;
    font-size: 0.85rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    position: relative;
    z-index: 2;
}

.refund-copy-all-btn:hover {
    transform: scale(1.05);
    box-shadow: 0 4px 12px rgba(245, 158, 11, 0.3);
}

.refund-result-content {
    position: relative;
    z-index: 2;
}

.refund-result-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 0;
    border-bottom: 1px dashed var(--card-border);
}

.refund-result-item:last-of-type {
    border-bottom: none;
}

.refund-result-label {
    font-size: 0.9rem;
    color: var(--text-muted);
    font-weight: 500;
}

.refund-result-value {
    font-size: 1rem;
    color: var(--text-main);
    font-weight: 600;
}

.refund-result-formula {
    margin-top: 16px;
    padding: 16px;
    background: var(--input-bg);
    border-radius: 12px;
    font-size: 0.82rem;
    line-height: 2;
    color: var(--text-muted);
    font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
    white-space: pre-wrap;
    word-break: break-all;
    border: 1px solid var(--card-border);
    max-height: 500px;
    overflow-y: auto;
}

.refund-result-formula .formula-line {
    margin-bottom: 4px;
    padding: 2px 0;
}

.refund-result-formula .formula-line:last-child {
    margin-bottom: 0;
}

.refund-result-formula::-webkit-scrollbar {
    width: 6px;
}

.refund-result-formula::-webkit-scrollbar-track {
    background: var(--card-bg);
    border-radius: 3px;
}

.refund-result-formula::-webkit-scrollbar-thumb {
    background: var(--theme-refund);
    border-radius: 3px;
}

.refund-result-formula::-webkit-scrollbar-thumb:hover {
    background: var(--theme-refund);
    opacity: 0.8;
}

.refund-result-amount-item {
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
}

.refund-result-amount-wrapper {
    display: flex;
    flex-direction: column;
    gap: 4px;
    width: 100%;
}

.refund-result-calc {
    font-size: 0.8rem;
    color: var(--text-muted);
    font-family: 'Consolas', 'Monaco', monospace;
    line-height: 1.5;
}

.toast { position: fixed; bottom: 30px; left: 50%; transform: translateX(-50%) translateY(20px); background: var(--text-main); color: var(--bg-color); padding: 10px 24px; border-radius: 30px; font-weight: 600; opacity: 0; pointer-events: none; transition: all 0.3s; z-index: 100; box-shadow: 0 10px 25px rgba(0,0,0,0.2); }
.toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }

@media (max-width: 600px) {
    .refund-row {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 600px) {
    .container { padding: 14px; }
    .card { padding: 16px; }
    .main-input { font-size: 2rem; }
    .bw-visualizer { flex-direction: column; gap: 16px; }
    .bw-divider { transform: rotate(90deg); }
    .dl-grid { grid-template-columns: 1fr; }
    .theme-toggle { position: static; margin-left: auto; }
    .top-bar { justify-content: space-between; gap: 10px; }
    .nav-wrapper { margin: 0 auto; }

    .est-row {
        grid-template-columns: 1fr;
        gap: 8px;
    }
    .est-swap-btn {
        margin-top: 0;
        justify-self: center;
        transform: rotate(90deg);
    }
    .est-swap-btn:hover { transform: rotate(270deg) scale(1.15); }
    .est-input { font-size: 1.1rem; padding: 8px; }
    .est-result-time { font-size: 1.6rem; }
    .est-result-box { padding: 16px 12px; }
    .est-block { padding: 12px; }
}

@media (max-width: 380px) {
    .container { padding: 10px; }
    .card { padding: 12px; }
    .est-scenarios { grid-template-columns: 1fr; }
}