/* styles.css */
:root {
    --primary: #003366;       /* PDO Blue */
    --primary-dark: #002244;
    --accent: #ffcc00;        /* Safety Yellow */
    --bg: #f0f2f5;
    --text: #2c3e50;
    --white: #ffffff;
    --success: #27ae60;
    --danger: #e74c3c;
    --sidebar-width: 280px;
}

* { box-sizing: border-box; margin: 0; padding: 0; font-family: 'Segoe UI', system-ui, sans-serif; }

body { background-color: var(--bg); color: var(--text); padding: 30px; }

/* SHARED COMPONENTS */
h1 { color: var(--primary); font-size: 2.2rem; margin-bottom: 25px; border-left: 10px solid var(--accent); padding-left: 20px; font-weight: 800; }
h2, h3 { color: var(--primary); margin-bottom: 15px; }

/* CARDS */
.card { background: white; border-radius: 12px; padding: 25px; box-shadow: 0 4px 15px rgba(0,0,0,0.05); margin-bottom: 20px; }
.card-header { background: #f8f9fa; padding: 15px 25px; margin: -25px -25px 20px -25px; border-bottom: 1px solid #eee; font-weight: bold; color: var(--primary); border-radius: 12px 12px 0 0; }

/* BUTTONS */
.btn { background: var(--primary); color: white; border: none; padding: 12px 24px; border-radius: 6px; cursor: pointer; font-weight: bold; transition: 0.2s; }
.btn:hover { transform: translateY(-2px); box-shadow: 0 5px 15px rgba(0,0,0,0.2); }
.btn-reset { background: #7f8c8d; }

/* INPUTS */
input, select { padding: 10px; border: 1px solid #ccc; border-radius: 5px; width: 100%; margin-bottom: 10px; font-size: 1rem; }

/* TABLES */
table { width: 100%; border-collapse: collapse; background: white; border-radius: 8px; overflow: hidden; margin-top: 10px; }
th { background: var(--primary); color: white; padding: 12px; text-align: left; }
td { border-bottom: 1px solid #eee; padding: 10px; }

/* ACCORDION (For Plan & RAMS) */
.accordion { background: white; border-radius: 8px; margin-bottom: 10px; border-left: 5px solid #ccc; overflow: hidden; }
.accordion.active { border-left-color: var(--success); }
.acc-header { padding: 15px; cursor: pointer; font-weight: bold; display: flex; justify-content: space-between; background: #fff; }
.acc-header:hover { background: #f9f9f9; }
.acc-body { max-height: 0; overflow: hidden; transition: 0.3s; padding: 0 15px; background: #fafafa; }
.accordion.open .acc-body { max-height: 500px; padding: 15px; border-top: 1px solid #eee; }

/* TEACHING STEPS (For Exercises) */
.step-box { background: #fff; border-left: 4px solid var(--accent); padding: 15px; margin-bottom: 10px; display: none; animation: fadeIn 0.4s; }
.step-box.visible { display: block; }
.final-ans { background: var(--success); color: white; padding: 15px; text-align: center; font-weight: bold; border-radius: 6px; display: none; margin-top: 10px; }
.final-ans.visible { display: block; }

@keyframes fadeIn { from { opacity: 0; transform: translateY(5px); } to { opacity: 1; transform: translateY(0); } }