/* ============================================================
   Compound Interest Visualizer — Emerald Dark Theme
   ============================================================ */

:root {
  --primary: #10B981;
  --primary-dim: rgba(16, 185, 129, 0.12);
  --secondary: #34D399;
  --accent: #F59E0B;
  --accent-dim: rgba(245, 158, 11, 0.12);
  --bg: #0A140A;
  --bg-card: #111D11;
  --bg-surface: #1A2E1A;
  --bg-input: #0D180D;
  --border: rgba(16, 185, 129, 0.12);
  --border-hover: rgba(16, 185, 129, 0.3);
  --text: #E2E8F0;
  --text-dim: #94A3B8;
  --text-muted: #64748B;
  --radius: 12px;
  --radius-sm: 8px;
  --font: 'Inter', -apple-system, BlinkMacSystemFont, system-ui, sans-serif;
  --mono: 'JetBrains Mono', 'Fira Code', monospace;
  --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 16px; -webkit-font-smoothing: antialiased; }
body { font-family: var(--font); background: var(--bg); color: var(--text); min-height: 100vh; }

.app { max-width: 960px; margin: 0 auto; padding: 0 20px 60px; }

/* Header */
.header { padding: 32px 0 16px; text-align: center; }
.header-content { display: flex; flex-direction: column; align-items: center; gap: 4px; }
.logo { display: flex; align-items: center; gap: 10px; }
.logo-icon { font-size: 1.6rem; }
.logo-text {
  font-size: 1.4rem; font-weight: 700;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
}
.tagline { font-size: 0.82rem; color: var(--text-muted); margin-top: 4px; }

/* Buttons */
.btn-primary, .btn-secondary {
  padding: 10px 20px; border: 1px solid var(--border); border-radius: var(--radius-sm);
  font-family: var(--font); font-size: 0.85rem; font-weight: 600; cursor: pointer; transition: all var(--transition);
}
.btn-primary { background: var(--primary); color: #000; border-color: var(--primary); }
.btn-primary:hover { box-shadow: 0 0 20px rgba(16, 185, 129, 0.3); transform: translateY(-1px); }
.btn-secondary { background: var(--bg-card); color: var(--text); }
.btn-secondary:hover { border-color: var(--border-hover); }

/* Input Panel */
.input-panel {
  background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 20px; margin-bottom: 20px;
}

.inputs-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap: 14px; margin-bottom: 16px; }

.field { display: flex; flex-direction: column; gap: 4px; }
.label { font-size: 0.72rem; font-weight: 600; color: var(--text-muted); text-transform: uppercase; letter-spacing: 0.04em; }

.input {
  padding: 8px 12px; background: var(--bg-input); border: 1px solid var(--border); border-radius: 6px;
  color: var(--text); font-family: var(--font); font-size: 0.85rem; outline: none; transition: border-color var(--transition);
}
.input:focus { border-color: var(--primary); }

.input-actions { display: flex; gap: 10px; flex-wrap: wrap; }

/* Summary Cards */
.summary-cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 12px; margin-bottom: 20px; }

.summary-card {
  background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 16px; text-align: center;
}
.summary-value { font-size: 1.5rem; font-weight: 700; font-family: var(--mono); color: var(--secondary); }
.summary-label { font-size: 0.72rem; color: var(--text-muted); text-transform: uppercase; margin-top: 4px; }
.summary-card.accent .summary-value { color: var(--accent); }

/* Rule of 72 */
.rule72 {
  background: var(--accent-dim); border: 1px solid rgba(245, 158, 11, 0.2); border-radius: var(--radius);
  padding: 14px 20px; margin-bottom: 20px; display: flex; align-items: center; gap: 12px;
}
.rule72-icon { font-size: 1.2rem; }
.rule72-text { font-size: 0.85rem; color: var(--text); }
.rule72-value { font-weight: 700; color: var(--accent); font-family: var(--mono); }

/* Chart */
.chart-section {
  background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius);
  overflow: hidden; margin-bottom: 20px;
}
.chart-header { display: flex; justify-content: space-between; align-items: center; padding: 12px 16px; border-bottom: 1px solid var(--border); flex-wrap: wrap; gap: 8px; }
.panel-title { font-size: 0.85rem; font-weight: 600; color: var(--text-dim); }
.chart-legend { display: flex; gap: 14px; }
.legend-item { display: flex; align-items: center; gap: 4px; font-size: 0.72rem; color: var(--text-muted); }
.legend-dot { width: 8px; height: 8px; border-radius: 50%; }

.chart-container { padding: 16px; overflow-x: auto; }
canvas { width: 100%; height: auto; display: block; }

/* Table */
.table-section {
  background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius);
  overflow: hidden;
}
.table-section .panel-title { padding: 12px 16px; border-bottom: 1px solid var(--border); }
.table-wrapper { overflow-x: auto; }

.data-table { width: 100%; border-collapse: collapse; }
.data-table th, .data-table td { padding: 10px 16px; text-align: right; white-space: nowrap; font-size: 0.82rem; }
.data-table th { background: var(--bg-surface); color: var(--text-muted); font-weight: 600; font-size: 0.72rem; text-transform: uppercase; position: sticky; top: 0; }
.data-table td { border-top: 1px solid var(--border); font-family: var(--mono); }
.data-table tr:hover td { background: rgba(16, 185, 129, 0.04); }
.data-table td:first-child { text-align: center; color: var(--text-dim); }

.milestone-row td { color: var(--accent) !important; font-weight: 600; }

@media (max-width: 640px) {
  .inputs-grid { grid-template-columns: 1fr; }
  .summary-cards { grid-template-columns: 1fr 1fr; }
}